Psychological relaxation techniques in sports: The acute effects of relaxation techniques between physical tasks

Kumulative Dissertation zur Erlangung des akademischen Grades eines Doktors der Philosophie (Dr. Phil) im Fach Sportpsychologie

Maximilian Pelka

Ruhr-Universität Bochum Fakultät für Sportwissenschaft im Jahr 2017

RUHR-UNIVERSITÄT BOCHUM Fakultät für Sportwissenschaft Lehr- und Forschungsbereich Sportpsychologie

Psychological relaxation techniques in sports: The acute effects of relaxation techniques between physical tasks

Von der Fakultät für Sportwissenschaft der Ruhr-Universität Bochum genehmigte kumulative Dissertation zur Erlangung des akademischen Grades eines Doktors der Philosophie im Fach Sportpsychologie

vorgelegt von Maximilian Pelka E-Mail: [email protected]

Betreuer Prof. Dr. Michael Kellmann

Bochum, Januar 2017

Dissertation vorgelegt von: Maximilian Pelka [email protected]

Eingereicht am 25.01.2017

Erstgutachter: Prof. Dr. Michael Kellmann Zweitgutachter: Dr. Jamie Barker

Erstprüfer: Prof. Dr. Michael Kellmann

Abstract for the Dissertation „Psychological relaxation techniques in sports: The acute effects of relaxation techniques between physical tasks“

submitted on 25.01.2017 by Maximilian Pelka

Training und Wettkampf sind für Athleten hoch belastend. Ohne ausreichende Erholung ist dementsprechend keine optimale Leistung möglich. Der genaue Erholungsbedarf ist allerdings individuell unterschiedlich. Ein stark beanspruchendes Ereignis für eine Athletin kann als weniger beanspruchend von einer anderen wahrgenommen werden. Jede Athletin nimmt Belastungen anders wahr und sollte folglich verschiedenen Strategien folgen. Eine Art von Erholungsstrategien sind systematische Entspannungstechniken. Die akute Wirksamkeit dieser Techniken auf sportspezifische Leistungsfähigkeit wurden in der vorliegenden Dissertation untersucht und diskutiert. Die Ergebnisse geben einen weitreichenden Überblick darüber, welche Entspannungstechniken erfolgreich im Sport eingesetzt werden und empirisch untersucht wurden. Darüber hinaus trägt diese Dissertation zur Etablierung eines grundlegenden Verständnisses der Anwendung von Entspannungstechniken im Sport bei.

The sport environment is highly demanding for its actors. Without adequate recovery, optimal performance is not attainable. It depends, however, on the individual what adequate recovery is. An extremely demanding event for someone must not be as demanding for someone else. Every individual perceives its environment differently and should follow different strategies consequently. A special set of recovery strategies are systematic relaxation techniques. The acute effects of these techniques on performance are examined and discussed in the present dissertation. Altogether, the collective results of this dissertation give a distinctive overview on which relaxation techniques are successfully used and examined in sport settings. Furthermore, the dissertation contributes to the establishment of a fundamental understanding of the application of relaxation techniques in sports.

Psychological relaxation techniques in sports

Table of contents

List of figures ------II

Urheberschaftserklärung (Credit attributions and acknowledgements) ------III

1 Introduction ------4

2 Recovery ------5

3 Relaxation ------8

3.1 Psychological and physiological background of relaxation ------9

3.2 Relaxation techniques ------12

3.2.1 Situational and environmental influences ------14

4 Purpose of the current research ------15

4.1 Hypotheses ------15

5 Overview of publications: Psychological relaxation techniques in sports ------17

6 Discussion ------18

6.1 Discussion of the results ------18

6.1.1 Relaxation techniques in sports ------18

6.1.2 Acute effects of relaxation techniques ------21

6.1.3 Effects of a disturbed break ------25

6.2 General discussion and perspective ------27

7 Conclusion ------30

8 References ------31

List of figures

Figure 1. The scissor’s model ------7

Figure 2. Relaxation techniques as the basement of recovery skills ------8

II

Urheberschafterklärung

Hiermit versichere ich, dass ich die vorgelegte kumulative Dissertation selbst und ohne fremde Hilfe verfasst, nicht andere als die in ihr angegebenen Quellen oder Hilfsmittel benutzt, alle vollständig oder sinngemäß übernommenen Zitate als solche gekennzeichnet sowie die Dissertation in der vorliegenden oder einer ähnlichen Form noch bei keiner anderen in- oder ausländischen Hochschule anlässlich eines Promotionsgesuchs oder zu anderen Prüfungszwecken eingereicht habe.

Die der vorliegenden kumulativen Dissertation zugrundeliegenden Publikationen in internationalen Fachzeitschriften mit Review-Verfahren entstanden aus eigenständig durchgeführten Untersuchungen. Als Coautor war Prof. Dr. Michael Kellmann zu Teilen an der Konzeption der Untersuchungen sowie an wichtigen Korrekturen bei der Erstellung der Manuskripte beteiligt. Darüber hinaus gab er Unterstützung bei der Auswahl der geeigneten Fachzeitschriften und im Review Prozess. Alle weiteren Coautoren, Prof. Dr. Alexander Ferrauti, Prof. Dr. Tim Meyer, Prof. Dr. Mark Pfeiffer, Dr. Sarah Kölling und Jahan Heidari, waren zudem ebenfalls mit wichtigen Korrekturhilfen an der Erstellung einzelner Manuskripte beteiligt. Ich selbst war sowohl für die Konzeption und Durchführung der Untersuchungen sowie für die Aufarbeitung, Analyse und Interpretation der Daten zuständig. Desweitern war ich auch für die Formulierung und Revisionen der Manuskripte verantwortlich.

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Bochum, den 25.01.2017 Maximilian Pelka

III Introduction

1 Introduction The intense mental and physical demands placed on elite athletes are important aspects of a sporting career (Walsh, 2015). Impacted by a variety of bio-psycho-social factors optimal performance in sports and increased overall well-being is only achievable if demands are paired with appropriate and adequate recovery. As demands are multifactorial (Nédélec et al., 2013) and interdependent (Marcora, Staiano, & Manning, 2009; Sutherland, Alexander, & Hutchinson, 2006), recovery needs to be multi- and interdisciplinary as well. For recovery to be holistic, biological, emotional, behavioural, social, physiological and psychological parameters need to be considered. For example, physical recovery (Hausswirth & Mujika, 2013) following dehydration, glycogen depletion, and muscle damage (Nédélec et al., 2012) or psychological recovery following mental fatigue (Nédélec et al., 2013) need to be addressed. Moreover, competitive anxiety must be dealt with (e.g., Fletcher & Hanton, 2001; Neil, Mellalieu, & Hanton, 2006) to the same degree as competition and organisational demands (e.g., Fletcher, Hanton, Mellalieu, & Neil, 2012). Explicit variables that play crucial roles are for example, factors intrinsic to the sport (e.g., training and competition), roles in the sport organization (e.g., role conflicts and ambiguity), sport relationships and interpersonal demands (e.g., fit of personality types), athletic career and performance development issues (e.g., income and funding, career goals, position insecurity), organizational structure and climate of the sport (e.g., cultural and political environment, coaching style, inadequate communication channels; Fletcher et al., 2012). All those factors are contributors to optimal performance and well-being and need to be balanced out adequately. As training and competition schedules are getting denser, the time between these events should be highlighted and explored thoroughly (Meyer, Kellmann, Ferrauti, Pfeiffer, & Faude, 2013).

Focusing on training and competition, Raysmith and Drew (2016) revealed that performance success or failure is influenced by an athlete’s health status during preparation for competition. They reported that training loss of around 20 per cent due to injury or illness decreased the likelihood of achieving a performance goal by seven times. Therefore, an athlete’s health status and its influence on training availability is a major determinant of an athlete’s chance of performance goal success or failure (Raysmith & Drew, 2016). It was also shown that inadequate recovery between matches because of a congested match calendar can lead to fatigue and increase the risk of injury associated with overuse and poor performance during subsequent performance (Dupont et al., 2010; Laux, Krumm, Diers, & Flor, 2015). This view is shared by Meeusen et al. (2013) who stated, that successful training most likely involves overload while avoiding the combination of excessive overload and inadequate recovery. Therefore, it is

4 Introduction essential to implement appropriate recovery phases and strategies in training regimens that aim for well-being and competitive success, both with a short- and long-term focus.

Consequently, the integration of recovery is a crucial part of any performance system. To be able to produce optimal performances individuals should be prepared to respond to bio-psycho- social demands adequately as these demands affect a person’s health status and have the potential to interfere with one’s performance goals. Sustained “inability” dealing with these demands could lead to critical disadvantages quickly (Rice, Purcell, De Silva, Mawren, McGorry, & Parker, 2016). Therefore, recovery, either as a response to demands or as a continuous state, is needed to perform optimally (Nédeléc et al., 2012, 2013; Raysmith & Drew, 2016). Within this construct, systematic relaxation is a promising way to initiate and to support recovery (Brown & Fletcher, 2017). The following work will discuss recovery and relaxation techniques in sports and its acute effects on performance in detail.

2 Recovery

The basic idea of recovery is that resources need to be restored and a homeostatic and biorhythmic balance regained. Kallus and Kellmann (2000) described the recovery process as an inter- and intra-individual multilevel process for the reestablishment of performance abilities. It includes an action-oriented component and self-initiated activities that can be systematically used to optimize situational conditions to build and restore personal resources and buffers. Based on this definition, it ends when a psychophysiological state of restored efficiency and homeostatic balance is achieved. This multilevel process is highly individual and has several dimensions, i.e., physiological, mood-related, psychological, behavioural, social, and emotional recovery (Kallus & Kellmann, 2000). Essentially, recovery depends on a reduction of, a change of, or a break from stress and is a gradual and cumulative process that is dependent on previous activities (Kellmann, 2002). In addition, recovery is tightly linked to environmental circumstances. It is dependent on whether requirements for optimal recovery are provided or not. For example, if one is disturbed in their preparation between two downhill skiing runs, it possibly influences the second leg.

Practically, recovery can be divided into active, passive, and pro-active methods (Kellmann, 2002). Active recovery involves moderate exercise during the recovery process to eliminate the results of fatigue through a target-oriented physical activity (e.g., low-intensity cycling for a certain amount of time on an ergometer after a Tour de France stage). A passive approach could consist of hot and cold baths, massages, sauna or sitting and lying quietly. Thereby,

5 Recovery physiological reactions to physiological stimuli such as heat, cold, or pressure are initiated and include psychological and biological processes to restore pre-task/performance states. Whenever recovery includes a purposeful, self-initiated and self-determined action, it can be understood as pro-active recovery (e.g., stretching to overcome the time span of a medal ceremony when there is competition on the following day or taking a post lunch nap before late scheduled video analyses). One’s perception of recovery is important as well; if it is positive, crucial improvements in outcomes are likely (Botterill & Wilson, 2002). Recent research in football (Fullagar et al., 2016), rowing (Kölling et al., 2016), weightlifting (Schimpchen et al., 2016), strength training (Raeder et al., 2016), and cycling (Hammes et al., 2016) show the high value of the recovery process in different settings.

Interrelation between recovery and demands

Optimal performance is only achievable if performers are recovered appropriately after exposition to demanding activities, and optimally balance stress with adequate recovery (Kellmann, 2010). In any performance system in contemporary society, people are confronted with an enormous work load and an increasing amount of competition (Zeidner & Ben-Zur, 2014). Individuals have to invest a large amount of time and intense effort to stay on top in their area of expertise. Every field has its own demands and specialties to which one must respond to. In order to deal effectively with such demands, individuals need to rely on their resources. Introduced into recovery/stress research three decades ago, resources can be divided into consumptive and permanent resources (Schönpflug, 1983). Acutely demanding issues, e.g., the duty to secure a lead in the last minutes of a match, affect consumptive resources in the first instance. The response to these issues mobilises and utilises resources to allow an active coping, such as extra sprints that have to be made to secure the lead. Chronically occurring demands are more prone to have negative effects on permanent resources (Kallus, 2016), e.g., dealing with insults of fans of an opposing team in every away match. Additionally, permanent resources could be at stake in acute stress situations. Kellmann (2002) described the interplay between stress states and recovery demands of an individual based on the assumption that an individual has limited resources to compensate for and cope with stressors (Hampel & Petermann, 2006). Under increased stress and the inability to meet increased recovery demands (i.e., low quality of necessary recovery activities to level-out the current recovery-stress state), individuals experience even more stress. At this moment, they may be stressed to the point that they fail to find or invest time to adequately recover, or to consider better ways of coping with their demanding situations. Failing to adapt may potentially lead to even more stress, resulting

6 Recovery in the need for more recovery time. This situation can be handled until the recovery demands surpass the resource limit or the stress states exceed the stress capacity (see Figure 1). Beyond these boundaries, an athlete cannot meet recovery demands without additional recovery activities. Stress will accumulate and without intervention severe consequences are more likely to occur (Meeusen et al., 2013). However, being highly stressed does not necessarily imply negative consequences if one is able to react with an adequate amount of recovery. This interrelationship is very individual; one athlete might tolerate a lot of demands and does not need much compensation but another might need it (Kellmann, 2002).

Figure 1. The scissor’s model (Kellmann, 1997, p. 14)

Recovery in both cases - either as a response to demands or as a continuous state that is needed to be able to perform - is closely connected to the tasks or the demands one is exposed to. Therefore, performance characteristics are of high value and great interest when examining recovery-stress states. Birrer and Morgan (2010) adapted a model developed by Schnabel, Harre, and Krug (2008) on the potential psychological skills an athlete needs to cope with the demands and requirements of world-class sport performance dependent on the different disciplines. Following Birrer and Morgan (2010, Figure 2) trained recovery skills are an essential factor, which affect training scope, training intensity, training years, injury and death risks, duration of competition impact, intensity of the competition impact, and continuity of the competition impact. However, it is still unclear which strategy would be the most effective for which sport and which situation. In any case, recovery should be a consciously-planned activity that matches situational and environmental needs of an athlete in rest and results in regaining

7 Recovery an optimal performance state. Birrer and Morgan (2010) and Kellmann (2002) suggest that recovery skills are enhanced by systematic relaxation techniques.

Figure 2. Relaxation techniques as the basement of recovery skills. Excerpt from Birrer and Morgan (2010, p. 81)

3 Relaxation

Having appropriate recovery strategies is a crucial part of a successful recovery process, and includes a variety of ways to achieve a state of well-being and performance enhancement (Kaur, Agarwal, & Babbar, 2014; Kudlackova, Eccles, & Dieffenbach, 2013). People sleep, nap, or meditate to calm down from the various demands they were exposed to. Even running, dancing or other strenuous exercises could be declared relaxing if they are appraised as relaxation. A certain range of recovery strategies, i.e., systematic relaxation techniques, have been examined thoroughly and obtained scientific back-up, experimental support, and validation. Those techniques are standardized methods applied and validated in clinical settings (e.g., Conrad & Roth, 2007). The application of these methods in clinical settings has introduced a more exact and differentiated understanding of relaxation. It is a psychophysiological process which is located on an individually different reference point on a continuum between activation (e.g., intense excitement) and deactivation (e.g., deep sleep) (Vaitl, 2014; Weinberg & Gould, 2010). It consists of physiological reactions which are an inherent part of human behaviour (further explanations will be provided in section 4.1). All the different relaxation techniques potentially lead to a variety of psychological and physiological changes which are summarized under the umbrella term relaxation response. These relaxation techniques are utilized as therapeutic support in the treatment of psychological and physiological disorders. More specifically, these disorders include, e.g., anxiety disorders, aggressive behaviour, attention deficit hyperactivity disorder, stress-related disorders, adaption disorders (psychologically based disorders; Broadbent et al., 2012; Crawford, Wallerstedt, Khorsan, Clausen, Jonas, & Walter, 2013), or sleep disorders, hypertonia, coronary heart diseases, asthma bronchiale, or gastrointestinal

8 Relaxation disorders (physiologically based disorders; e.g., Lohaus, Klein-Hesseling, Vögele, & Kuhn- Henninghausen, 2001; Lübbert, Dahme, & Hasenbring, 2001; Petermann & Vaitl, 2014).

Petermann and Vaitl (2014) reported hypnosis, autogenic training, meditational (eastern) techniques, imagery, progressive muscle relaxation (PMR) and biofeedback as being the standard repertoire of techniques which are known to induce relaxation. Following Kudlackova et al. (2013) autogenic training, eastern relaxation, and progressive muscle relaxation were the less used techniques compared to deep breathing, meditation and imagery in a study investigating the use of relaxation techniques in professional and semi-professional sports. Previous research has divided these techniques into two separate paths (Davidson & Schwartz, 1976; Kenttä & Hassmén, 1998). Muscle-to-mind techniques focus on the training of one’s sensitivity to muscle tension (e.g., PMR, breathing techniques) while mind-to-muscle techniques focus on the cognitive processes involved in relaxation (e.g., autogenic training, hypnosis). Furthermore, techniques with predominant autonomic components (e.g., hypnosis) tend to produce greater effects on the autonomic nervous system (e.g., decreases in heart rate and blood pressure, increases in finger pulse volume, etc.); and methods with predominant skeletal muscle components (e.g., PMR, Biofeedback) tend to produce greater muscular effects (e.g., release of muscle tension). These subdivisions will be explained in more detail in section 4.2. Although all these techniques share basic integral parts, each method has a different impact on the individual. Shared parts are, e.g., the establishment of self-control, concentration training, relaxation, and an improvement of well-being. To achieve these aims consistently, systematic relaxation needs to be taught and practised (Petermann & Vaitl, 2014).

3.1 Psychological and physiological background of relaxation

The introduction of the psychophysiology of the relaxation response goes hand in hand with the introduction to the functions of the nervous system. To provide a general understanding (on which parts are important concerning relaxation), the nervous system will be described briefly.

Regarding the general psychophysiological background of relaxation, neuro-muscular, cardio- vascular, respiratory, electro-dermal, and central nervous system related changes based on the relaxation response have been examined (Andreassi, 2007). All these changes are under the control of the nervous system, which is divided into two main branches, the central (CNS) and the peripheral nervous system. The CNS includes the brain and the spinal cord. The peripheral nervous system refers to nervous tissue outside of the brain and spinal cord, including cranial and spinal nerves. The peripheral nervous system is further divided into the somatic nervous

9 Relaxation system (responsible for muscular activities) and the autonomic nervous system (ANS; controlling visceral structures). Lastly, the ANS is subdivided into the parasympathetic nervous system (PNS), which is dominant when the individual is at rest, and the sympathetic nervous system (SNS), which is dominant in situations that require the mobilisation of energy. Because of these characteristics, the last two subdomains are of great interest when examining relaxation and especially the relaxation response.

Measuring relaxation

The relaxation response includes a variety of possible psychological and physiological changes (Andreassi, 2007). Knowing that the nervous system is highly integrated, for practical reasons research has listed the various measures as being primarily controlled by subdivisions of that system. For example, heart rate, blood pressure, blood volume, and electrodermal activity may serve as measures of autonomic nervous system activity (e.g., Dolbier & Rush, 2012; Jerath, Crawford, Barnes, & Harden, 2015; Lewis, Williams, & Olds, 2007). Explicit physiological characteristics of relaxation are, e.g., the deceleration and “rhythmitisation” of the respiration rate, a reduction of the O2-consumption, a decrease in heart rate and blood pressure, an increase in the skin conductance level, a decrease in skeletal muscle tonus, or an increase in the activation of the digestive system. All of the above-mentioned responses could be measured through respective wearables (e.g., heart rate monitor, biofeedback applications, respiration belts, electrooculography, electroencephalogram, event-related brain potential, or electromyogram). Based on an intensive review of the area, Andreassi (2007) concludes that it is impractical to actually measure all of these responses at once. In order to create a situation that is as natural as possible and allows an individual to relax, the focus should be on one or two physiological measures.

On a psychological base, the relaxation response includes an increase in the ability to focus, an increase in well-being, a reduction of anger and arousal, a decrease in lack of activation, a possible increase in self-confidence, the establishment of an inner balance, and the possible prevention of insomnia (Smith, 1999). An assessment option are psychometric instruments, which are most commonly conducted as self-reports. If completed honestly, these self- monitoring procedures have been recognized to accurately display one’s recovery and stress state. This is supported by Thorpe, Strudwick, Buchheit, Atkinson, Drust, and Gregson (2016) who found that perceived ratings of wellness are more sensitive than HR-devices to the within- week fluctuations in training load experienced by elite football players during in-season training weeks. The authors furthermore conclude that these ratings seem to be particularly helpful in

10 Relaxation terms of being a non-invasive assessment of fatigue states in elite sports. Considering the increasingly scientific approach of modern sports to athletic preparation by means of athlete monitoring as highlighted by Saw, Kellmann, Main, and Gastin (20176), athlete self-report measures hold great potential to provide valuable insight into the training response in the future. Saw et al. (2017) published a sophisticated overview on the most commonly used subjective measures in sports.

Developed for detecting acute changes, the recently published Acute Recovery Stress Scale (ARSS, Kellmann, Kölling, & Hitzschke, 2016) provides a promising self-report assessment tool. It consists of 32 adjectives, which are clustered into eight sub-scales, assessing acute recovery states on four sub-scales (Physical Performance Capability, Mental Performance Capability, Emotional Balance and Overall Recovery) and acute stress states on the remaining four (Muscular Stress, Lack of Activation, Negative Emotional State and Overall Stress). Example items include recovered, balanced and receptive. Answers have to be indicated on a 7-point Likert scale (0–6) with the extremes, “does not apply at all” and “fully applies”. Kellmann et al. (2016) reported satisfactory internal consistencies of at least α = .84 for all eight scales. A shorter form, the Short Recovery Stress Scale (Kellmann et al., 2016), is composed of eight items, derived from the originally 32 items of the ARSS. These items correspond with the eight sub-scales of the ARSS, accordingly categorised into four recovery- and four stress- related items. Answers have to be indicated on the same 7-point Likert scale as the ARSS. Internal consistencies for all dimensions of the SRSS were found to be satisfactory (α > .75). Through these self-monitoring measures acute imbalances between recovery and stress states can be detected (Fullagar et al., 2016; Hammes et al., 2016). The need for interventions could therefore be derived from respective results.

11 Relaxation

3.2 Relaxation techniques

Davidson and Schwartz’ matching hypothesis (1976), Kudlackova et al.’s study (2013), and Lehrer (1996) all suggest that muscularly-oriented methods have the greatest effects on the musculoskeletal system and autonomically-oriented methods on the autonomic nervous system. Strategies with predominant cognitive components were associated with decreases in amount of worrying, self-assessment of anxiety or pain, and an increase in the ability to concentrate (Jain et al., 2007). The most prominent techniques that fall thereunder are hypnosis and autogenic training. Hypnosis is defined as an altered state of consciousness that can be induced by a procedure in which a person is in an unusually relaxed state and responds to suggestions for making alterations in perceptions, feelings, thoughts, or actions (Barker & Jones, 2008). Autogenic training on the other hand, is a self-hypnotic method that uses trance-inducing procedures similar to hypnosis (Luthe & Schultz, 2001). Self-suggestions of heaviness and warmth in the limbs, a calm and regular heartbeat, coolness in the forehead, warmth in the solar plexus, and automatic breathing are common practices within autogenic training (Luthe & Schulz, 2001).

Strategies with predominant skeletal muscle components tend to produce greater muscular effects, e.g., a decrease in muscle tone and tension. Different versions of PMR, biofeedback, yoga, and systematic breathing are the most investigated techniques in this domain (Kudlackova et al., 2013).

Progressive muscle relaxation and its derivations have received the most attention in scientific context. Following the theoretical basement of Jacobsen (1938), the central aim of a relaxation technique is the deliberate and continuous reduction of tension in specific muscle groups of the locomotor system. The original method in which the emphasis is laid on training of self- perception of muscular sensations, has greater effects on somatic issues while the revised versions in which producing a subjective experience of relaxation is the key strategy, have a greater impact on cognitive symptoms (fears and anxieties; Dolbier & Rush, 2012). A review on the use of PMR in clinical trials revealed moderate to large effect sizes on the effectiveness of PMR (Crawford et al., 2013).

Similarly, systematic breathing (including relaxed basal breathing, diaphragmatic breathing, and abdominal breathing) is reported as being one of the simplest and most effective ways to control anxiety and muscle tension (Lewis et al., 2007). Williams and Harris (1998) state that inhaling and holding ones breathe increases muscle tension whereas exhaling decreases muscle

12 Relaxation tension. A slow and deliberate inhalation-exhalation sequence will help one to maintain composure and control over tension levels during stressful events (Weinberg & Gould, 2010). It is further operationalised as using the lower chest for breathing while relaxing the upper chest and shoulders (Pryor, Webber, & Bethune, 2002).

Yoga, with its roots in ancient Indian philosophy, is used for physical, mental, spiritual well- being and performance (Bhargav, Bhargav, Raghuram, & Garner, 2016; Doulatabad, Nooreyan, Doulatabad, & Noubandegani, 2012). More specifically, it has been found to be effective for addressing issues regarding strength, flexibility, balance, gait, anxiety, depression, and cognition enhancement (Salgado, Jones, Ilgun, McCord, Loper-Powers, & van Houten, 2013). Yoga practise affects general attentional abilities as it emphasizes body awareness and involves focusing one’s attention on breathing or specific muscles or parts of the body (Bhargav et al., 2016). It produces similar effects as relaxation, as it tends to promote self-control, attention and concentration, self-efficacy, body awareness, and stress reduction (Nardo & Reynolds, 2002). Research suggests that sympathetic activation occurs during the yoga posture phase and the parasympathetic nervous system becomes dominant after the practice during the relaxation phase (Bhargav et al., 2016; Sarang & Telles, 2006).

Further, biofeedback provides the individual with information of bio-signals, which are generated by physiological processes in the body and are generally inaccessible to the conscious perception. As a therapeutic measure, biofeedback pursues the goal of creating opportunities for the individual to voluntarily influence these processes. Basically, self-control over bodily processes is targeted. Biofeedback training is addressing oscillation by stimulating and exercising modulatory reflexes in the central nervous system, improvement of baroreflex functions, modulation of blood pressure and a decrease in anxiety and depression (Lehrer, 2012).

A method, which has not been defined as a systematic relaxation technique but is used widely as a recovery strategy, is the power nap (Petermann & Vaitl, 2014). Despite not belonging to the same group of techniques, one common overall goal of sleep and relaxation techniques is physiological restoration. Smith (1999) therefore termed sleep/power naps an essential but unrecognized relaxation process. An indication supporting this assumption might be that novice practitioners spend up to 50 percent of their relaxation in sleep in the early phases of relaxation training (Austin, 1998).

13 Relaxation

3.2.1 Situational and environmental influences

According to the overall recovery concept, research reports different goals of relaxation techniques for different application times (Baumann, 2006; Kellmann, 2002). There is a differentiation between short-term relaxation prior to competition, relaxation between training sessions or other demanding periods, and relaxation after training and/or competition. It was postulated that each intervention time had a different impact on the individual. The pre-task approach aims for improved concentration, self-reflection and mental rehearsal of the competition, the in-between task approach aims for the conservation of mental energy, and the post-task approach for the restoration of mental balance and an elaborate preparation for upcoming events. Whilst the majority of research on relaxation techniques in sports has focused on coping with anxiety and arousal regulation (e.g., Hanton, Wadey, & Mellalieu, 2008) a secondary function of relaxation, i.e., the promotion of short and long-term recovery has been neglected since Kellmann (2002) and others proposed its usefulness (Birrer & Morgan, 2010). Even though a few studies revealed effects of relaxation techniques on physiological parameters, such as a shortening of healing time or the reduction of stress (Broadbent et al., 2012), a positive influence on the cardiac parasympathetic tone (Sakakibara, Takeuchi, & Hayano, 1994), and a positive impact on recovery following sport injury (Schwab Reese, Pittsinger, & Yang, 2012) research needs to establish a more sophisticated background.

Regardless of the timing of relaxation techniques, unpredictable events and changes of conditions are likely to occur at any time. These changes can be of various natures, i.e., variations in environmental conditions (e.g., noise, heat, problems with facilities), self-related issues (e.g., rumination, tension, disturbing cognitions or inner conflicts), or even domestic issues (e.g., family problems, extra workload) and could have a deep impact on recovery. This phenomenon is termed disturbed recovery (Kellmann, 2002). It is present when requirements for optimal recovery are given the process though is interrupted by environmental issues (Kellmann, Altenburg, Lormes, & Steinacker, 2001). During these moments of deep concentration and attempted relaxation any disturbance could be experienced as a stressor. Other disciplines within psychology already focused on that field a few decades ago. A study by Roy (1963) showed that workers with scheduled breaks during their working days managed to focus their attention during the day and even experienced enjoyment. However, when these breaks were interrupted, workdays became almost intolerable.

14 Purpose of the current research

4 Purpose of the current research

Until now research was not able to reveal stable and valid results regarding the implementation and application of relaxation techniques in sports. Moreover, no systematic summary of those studies that examined acute effects of relaxation techniques exists. Therefore, the aim of this dissertation is to provide a systematic literature-based overview on the acute effects of psychological relaxation techniques in sports on performance. A second aim is the contribution of relevant research to the field, by the examination of basic performance-related effects, exemplarily presented within a simple physical task context. Thirdly, this approach is extended by an examination of effects of interrupted breaks on performance.

4.1 Hypotheses

1) The use of relaxation is frequently mentioned when (psychological) recovery is the topic of interest in sports (Kudlackova et al., 2013), but the extent to which these methods are based on experimental demonstrations of effectiveness and/or efficacy in sport settings has yet to be established. The same is true also for the extent to which the application of relaxation techniques in terms of timing of sessions, number of practice sessions, or duration of sessions affects outcome variables needs to be determined. Nevertheless, sport psychologists often advocate the use of relaxation skills to athletes and coaches, even though the lack of data in this area limits our understanding and expertise (Weinberg & Comar, 1994). Following Martin, Vause, and Schwartzman’s approach (2005) that focused on psychological interventions with athletes in competition, the question has been raised whether is it worth using them? This question may be answered by a systematic review of well-designed and executed randomized controlled trials (RCTs; Schultz, Chalmers, Hayes, & Altman, 1995). Therefore, the aim of this review is to provide an overview on the status quo of research on acute effects of psychological relaxation techniques in performance-oriented settings in sports (see Manuscript 5.1). At the same time such an endeavour may generate new hypotheses and thus path the way for future research.

2) Compared to clinical contexts (Broadbent et al., 2012; Hanton, Wadey, & Mellalieu, 2008; Kanji, 2000; Kanji, White, & Ernst, 2006), in sports, acute effects of relaxation techniques have only been shown sporadically. Based on the above-mentioned systematic review of relaxation techniques in sports performance contexts (Manuscript 5.1) it can be concluded that research to date is far away from providing valid guidelines for practitioners, highlighting the need for future studies with sound research designs and methods. Therefore, the first study aims to investigate whether relaxation techniques affect physical performance acutely and systematically in terms of

15 Purpose of the current research

being able to perform again after a certain amount of time in a sport-specific setting (see Manuscript 5.2).

3) As recovery breaks are not excluded from being interrupted occasionally and randomly, another question is apparent: What consequences occur when a break that aimed at inducing relaxation and preparing athletes for subsequent performances is disturbed? Thus, the aim of the third study is to examine whether an interruption of a recovery break negatively influences subsequent sports performance. In addition, it is assessed if those interruptions influence the subjective perception of a recovery break and subjective evaluation of one’s own recovery/stress state (see Manuscript 5.3).

16 Psychological relaxation techniques in sports

5 Overview of publications: Psychological relaxation techniques in sports1

Manuscript 5.1:

Relaxation techniques in sports: A systematic review on acute effects on performance

Pelka, M., Heidari, J., Ferrauti, A., Meyer, T., Pfeiffer, M., & Kellmann, M. (2016). Relaxation techniques in sports: A systematic review on acute effects on performance. Performance Enhancement and Health, 5(2), 47-59.

Manuscript 5.2:

Acute effects of psychological relaxation between two physical tasks

Pelka, M., Kölling, S., Ferrauti, A., Meyer, T., Pfeiffer, M., & Kellmann, M. (2017). Acute effects of psychological relaxation between two physical tasks. Journal of Sports Sciences, 35(3), 216-223.

Manuscript 5.3:

How does a short, interrupted recovery break affect performance and how is it assessed? A study on acute effects

Pelka, M., Ferrauti, A., Meyer, T., Pfeiffer, M., & Kellmann, M. (2017). How does a short, interrupted recovery break affect performance and how is it assessed? A study on acute effects. International Journal of Sports Physiology and Performance, 12(2), 114-121.

17 Discussion

6 Discussion

The present dissertation is based upon three studies on related aspects of relaxation techniques in sports. Firstly, a systematic review of the existing literature on acute effects of relaxation techniques on performance was conducted (Manuscript 5.1). This step was implemented to provide insight into which techniques have already been investigated in sport contexts. Considering the results of the review and additional literature suggestions an experiment was conducted to examine the acute effects of four relaxation techniques on performance (Manuscript 5.2). Lastly, it was investigated whether an interruption of a relaxation technique affected subsequent performance and the assessment of the relaxation technique itself (Manuscript 5.3). In the following paragraphs, the respective results, limitations, and potential application possibilities are discussed.

6.1 Discussion of the results

6.1.1 Relaxation techniques in sports

A decade ago the question was raised whether there is evidence-based support for using psychological interventions with athletes in sports competition settings in general (Martin et al., 2005). Based on methodological limitations of the articles the authors were only able to assess 15 studies. One of their first conclusions therefore was that generalisations from the results can only be made with caution. This corresponded with Greenspan and Feltz (1989) findings who reviewed 19 studies, including case reports and studies that used mock competitions as dependent measures. Other work with similar outputs during that time frame included reviews by Vealey (1994) as well as Weinberg and Comar (1994). More recently, Brown and Fletcher (2017) examined the effects of psychological and psychosocial interventions on sport performance systematically with a meta-analytical but more general approach. They included 35 studies and revealed that sports performance can benefit from the implementation of those interventions. In all those reviews, relaxation techniques were mentioned but existed only in a parenthetical way or as parts of multimodal programmes, e.g., Brown and Fletcher (2017) included five relaxation intervention studies in their review. Therefore, the question regarding a scientific and empirically supported base of relaxation techniques needed to be established in more detail. The purpose of Manuscript 5.1 was to critically review relaxation techniques that have been investigated with regards to performance outcomes. It is an important measure to emerge from these overviews that applied researchers require a greater understanding of the techniques that are effective at managing recovery/stress

18 Discussion balances. In addition, there is a need to provide practitioners with a greater awareness of the treatments that are deemed to be effective for optimising performance.

The outcomes of the systematic review showed that evidence regarding the use of relaxation techniques to enhance performance is scarce. Manuscript 5.1 supports previous reviews in their view on the insufficient methodological quality of studies that assessed relaxation techniques. However, the techniques that have been adequately examined yielded consistent performance enhancing effects. Biofeedback and hypnosis were found to be the most effective ones (see Manuscript 5.1).

Effects on performance and psychophysiology

Comparing the number of articles that fell under the first search rounds (8501 articles) with the number of studies that were finally selected (21 articles) in Manuscript 5.1, it must be stated that the status quo of the evidence base of relaxation techniques in sports (when considering their effects on performance) is rather poor. Many of the studies lacked appropriate research designs that could have allowed for adequate interpretation and conclusions (see Manuscript 5.1; Brown & Fletcher, 2017; Rew, Johnson, & Young, 2014; Rumbold, Fletcher, & Daniels, 2012). Nevertheless, those articles, which were not included in the respective reviews, walked on thin empirical ice and inferred causality from their studies with no scientific basement. This was already denounced by Greenspan and Feltz (1989). Other reviews dealing with relaxation techniques and/or stress management in the health domain reported similar issues (Rew et al., 2014; Rumbold et al., 2012). However, when considering the results of those studies that were selected, scientific proof for the acute effectiveness of the relaxation techniques in performance settings was found. In Manuscript 5.1 it was shown that 62 percent (13 trials) of the interventions led to a significant improvement of performance whilst 33 percent (six trials) stabilised performance and five percent (one trial) resulted in detrimental performance. This distribution resembles that of Brown and Fletcher (2017) who found an overall moderate effect of interventions on performance.

Contrary to these findings, in their review on stress management techniques (incl. relaxation techniques), Rumbold et al. (2012) reported that evidence regarding the intervention-performance relationship appeared to be weak. They found that stress management interventions were effective in terms of reducing stressors, modifying cognitive appraisals, reducing negative affect states, increasing positive affect states, and facilitating effective coping behaviour but only had small to no impact on performance. Therefore, reducing the negative perception of a demanding situation

19 Discussion does not necessarily imply improved performance (Rumbold et al., 2012). Rew et al. (2014), who as well examined stress management techniques, partly supported those findings. Without taking performance into account, their review revealed promising results, as most stress management interventions resulted in reduced self-report and physiological measures of stress. However, to combine performance outcomes with psychophysiological background, respective data must be collected systematically. According to psychophysiological research at least measuring one or two related variables is inevitable (Andreassi, 2007). Manuscript 5.1 revealed that regarding additional physiological data, only 12 out of 21 studies reported their data. Six of those studies reported improvement in heart rate, heart variability, or blood pressure measures that were accompanied by an improvement in performance. In order to draw conclusions, physiological, psychological, and performance data needs to be collected coherently.

Situational and environmental influences

Considering the diverse characteristics of sports performance and the effects of relaxation techniques in different circumstances, only trends can be reported. The application in terms of the timing of the sessions, the number of sessions, and the duration of sessions needs to be examined more thoroughly (Beckmann & Elbe, 2015). As the analyses of Manuscript 5.1 showed, effectivity of the different approaches was neither based on the number of sessions applied nor on the duration of the single sessions. The same holds for the timing of the sessions. A baseline for the frequency of training sessions could be three, as more than 75 percent of the included studies implemented a relaxation training programme with at least three sessions. Regarding single techniques, biofeedback has led to performance enhancement in six out of seven included trials. It was applied in settings involving accuracy tasks or performances with sprint distances. Hypnosis was involved in the same settings and led to consistent performance enhancing results as well (Manuscript 5.1). These results seem to promote that especially those settings are predestined for a successful implementation of relaxation techniques. A second consequence derived from these findings is contrary towards Davidson and Schwartz’s (1976) matching hypothesis which states that somatic-based relaxation has greater effects in reducing somatic stress while cognitive-based techniques reduce worry or cognitive stress. Following their theory, biofeedback and hypnosis stem from different relaxation branches, i.e., somatic- based or cognitive-based techniques. However, both techniques equally led to performance enhancement in physical (sprints) and cognitive (accuracy task) tasks. These conflicting findings support Smith’s (1999) assumption that research has to consider that effects can

20 Discussion possibly overlap. For example, PMR can have additional cognitive effects as well as meditation can have additional somatic effects (Smith, 1999).

The significance of the current findings is that only a few relaxation techniques (i.e., biofeedback and hypnosis) have been proven stable in their effects on performance variables. This might have been the case because hypnosis modifies the attentional focus and thereby increases awareness of the situational circumstances (Taylor, Horevitz, & Balague, 1993). Additionally, the threshold to pain can be significantly raised through hypnosis (Frankl, 1987). Both factors therefore provide a promising background for enhanced performance. On the other hand, biofeedback increases the direct voluntary control over physiological processes that are otherwise outside awareness (Pop-Jordanova & Demerdzieva, 2010). Consequently, activation levels can be regulated and physiological readiness for optimal performance assured. Others did not reflect the supportive effects that have been found in other disciplines such as medical or clinical psychology (Conrad & Roth, 2007). This might be the case because of the restricted number of publications examining the other techniques. Yoga and systematic breathing for example were tested only once; however, these studies revealed unreserved positive results (Donohue et al., 2006; Kim & Tennant, 1993). Direct influences of psychological relaxation techniques on the physiology of repeated sprint performance have not received sufficient attention yet (Manuscript 5.1). This needs to be considerered especially as it is generally suggested that elevated lactate levels after repeated sprinting impair subsequent performance by reducing the anaerobic energy contribution and by interfering with muscle contractile processes (Tschakert & Hofmann, 2013).

Thus, it is needless to say that the choice of the appropriate technique for the right situation needs to be determined by repeated evidence-based research in the relevant field. Nevertheless, a few techniques, which were only rarely systematically examined in sports, represent promising approaches as well (Smith, 1999). In the end, regardless of the various approaches, the full potential of relaxation techniques within recovery periods is not exploited yet and needs to be investigated more thoroughly and extensively. Even though, only a small number of studies examined the influence of relaxation techniques in sport settings and revealed performance enhancing effects, it is worth applying those (Brown & Fletcher, 2017). This is further supported by highly rare detrimental effects (Manuscript 5.1).

6.1.2 Acute effects of relaxation techniques

21 Discussion

It is established in research that relaxation leads to distinctive long-term effects and is more than symptom reduction (Smith, 1999). However, there are situations which require acute support. Previous research suggests that the greatest effects of relaxation techniques can be expected when a symptom precisely matches the specific goal of the technique (e.g., Davidson & Schwartz, 1976). The relaxation techniques, which were implemented in the study published in Manuscript 5.2, were applied to acutely counter the physiological and psychological demands between two repeated sprint bouts. From those techniques, systematic breathing and power naps led to consistent performance enhancement. Compared to progressive muscle relaxation, a relaxational yoga sequence, and a control group these two techniques significantly affected the performance in the second sprinting bout positively.

The repeated sprint setting consisted of a few important characteristics. Firstly, focusing on performance-related variables, fatigue is operationalised through a reduction in speed or maximal power output (Girard, Mendez-Villanueva, & Bishop, 2012). Secondly, concerning the autonomic nervous system, parasympathetic reactivation is highly impaired after repeated sprinting (Buchheit, Laursen, & Ahmaidi, 2007) and therefore the organism is not capable of conserving energy. It is generally agreed that with exercise, there is parasympathetic withdrawal and sympathetic excitation, resulting in acceleration of the heart rate. These effects are reversed in recovery (Goldberger, Le, Lahiri, Kannankeril, Ng, & Kadish, 2006). Unfortunately, data concerning the kinetics of recovery of autonomic function directly after the cessation of exercise are scarce (Mourot, Bouhaddi, Tordi, Rouillon, & Regnard, 2004). During short-term recovery (within 30 min after the termination of exercise), the decrease of heart rate toward resting baseline seems mainly related to the immediate resumption of parasympathetic activity (Perini, Orizio, Comande, Castellano, Beschi, & Veicsteinas, 1989). Thirdly, as a response to physiological stress, hormone (e.g., cortisol) and cytokine (e.g., interleukin-6) secretion is increased and results in a heightened inflammatory response (Abdelmalek et al., 2013). To support the recovery process and to enhance subsequent performance, relaxation techniques were implemented between two repeated sprint bouts. It was investigated whether different relaxation techniques affect physical performance acutely between two physical tasks (see Manuscript 5.2).

Effects on performance and psychophysiology

Following the results of Manuscript 5.2, systematic breathing as a basic and fundamental human action and at the same time the simplest one to control and manipulate, represents a relevant option to affect performance acutely. The findings of Manuscript 5.2 support the tendency revealed in

22 Discussion

Manuscript 5.1, i.e., that systematic breathing is potentially promising, though not sufficiently investigated in sports. A review by Lewis et al. (2007) revealed that when used as a sole intervention, there was a beneficial effect on outcomes related to the mechanism of breathing control as well as on short-term physiological outcomes. However, there was no clear evidence of a long-term effect on physiological outcomes. Lewis et al. (2007) concluded that the reviewed studies showed good generalisability and satisfactory quality but poor consistency in clinical settings.

The second performance-enhancing approach derived from Manuscript 5.2 was power napping. Generally, previous research has not only revealed that naps reduced subjective and objective sleepiness but also improved cognitive functioning, psychomotor performance and enhance short- term memory and mood (Brooks & Lack, 2006). It was further postulated that considerable benefits to alertness are consequences from brief (7–10 min of sleep) naps (Lovato & Lack, 2010). Additionally, even optimum time sequences for effects on mood, fatigue, objective performance, self-rated performance and objective alertness have been established (Hayashi, Ito, & Hori, 1999). A review by Halson (2014) comprehensively summarized sport-related effects of sleep. However, most of the studies described, examined participants with induced sleep deprivation. For example, an increase in performance and alertness and a decrease in sleepiness were found by Waterhouse, Atkinson, Edwards, and Reilly (2007) as well as Postolache and Oren (2005) revealed a positive effect of power naps on cognitive tasks after sleep deprivation. Results from Manuscript 5.2 support the performance enhancing functions of power naps and extend the findings to between- performance sports settings for regularly sleeping participants.

Systematic breathing and power naps both led to performance improvement and to relaxation response related measures in terms of heart rate adaption and self-reports (Manuscript 5.2). However, yoga relaxation and PMR led to similar physiological and self-report changes but not to performance enhancement. In the same vein, a review of treatments in music revealed that techniques such as deep muscle relaxation did not affect performance directly but improved self- report measures of performance anxiety and reduced heart rate (Kenny, 2005). These findings indicate that even though a relaxation response is elicited, it still depends on how the situational factors are in line with the specific characteristics of a certain relaxation technique whether performance is enhanced as well. Considering for example PMR, the relaxation response induced during this technique might be too intense (e.g., muscle tone is too low) to allow optimal subsequent performance. Future research has to extend the knowledge on this topic and reveal more about the exact links between performance enhancement and related physiology. This

23 Discussion should be done especially in consideration of the sports specific loads. In response to the repeated sprint performance in Manuscript 5.2, the development within the six sprints could be analysed as well by investigating the decrement scores (Hughes, Doherty, Tong, Reilly, & Cable, 2006). This approach specifically examines the relationship between an ideal time (i.e., the time of the first sprint multiplied by the number of repetitions) and the actual time (i.e., the sum of all sprints). However, the average maximum velocity used in the present study is the most reliable measure compared to mean force and percentage decrement scores (Hughes et al., 2006; Oliver, 2009).

Regarding the significant but small performance enhancing effects of systematic breathing and power napping further analyses could be executed additionally. To establish the clinical relevance of these interventions, magnitude-based inferences could be computed (Hopkins, Marshall, Batterham, & Hanin, 2009). This approach moves away from the traditional null- hypothesis test and confidence intervals to a more differentiating solution. Following Batterham and Hopkins (2005), based on 90% confidence intervals, magnitude-based inferences are qualified with a likelihood that the true value will have the observed magnitude of the outcome statistic. The range of the outcome interpretation is then applied from almost certainly beneficial (i.e., the value of the outcome statistic and the 90% confidence intervals lay within the beneficial/positive area) to very likely harmful (i.e., the value of the outcome statistic and the 90% confidence intervals lay within the negative/harmful area). Additionally, unclear effects can occur if the 90% confidence interval span includes all areas. Compared to the ANOVA’s applied in the present study this probabilistic rather then definitive statements would have added information on the magnitude of the effects and their clinical relevance to Manuscript 5.2 (Batterham & Hopkins, 2005). From the data of the study referring to Manuscript 5.2 in can derived that the effects of the systematic breathing and the power nap intervention are both possibly beneficial.

Situational and environmental influences

The setting constructed for Manuscripts 5.2 and 5.3 resembled a frequently occurring situation in competition or training; a 30 min break between demands, as occurring in gymnastics, track and field, multiple-leg disciplines in various winter sports, and team sports (Brooks et al., 1990). In addition to the similarities to sport settings, choosing this design had several other reasons. One of them was its ecological nature. Through repeated sprinting performances, it was possible to induce fatigue very fast and consistently in all participants (e.g., Hughes et al., 2006; Oliver, Williams, & Armstrong, 2006). Following previous research was another reason. As of the few studies that

24 Discussion tested the effects of relaxation techniques on performance, most of them used anaerobic sprinting or swimming tasks as performance indicators (Bar-Eli & Blumenstein, 2004; Bar-Eli, Dreshman, Blumenstein, & Weinstein, 2002; Blumenstein, Bar-Eli, & Tenenbaum, 1995; Donohue et al., 2006). However, those studies did not compare different techniques in their specific setting and were not able to draw conclusions. Furthermore, based on the physiological background it remains unclear whether the first repeated sprinting bout induced enough load in order to affect the second bout after a 30 min break. Next to the time and intensity of the workload, the applied intensity and duration of the recovery phase are to a great extent responsible for the acute physiological responses to repeated sprinting (Tschakert & Hofmann, 2013). This could explain that no drop in performance occurred in the second repeated sprinting bout. As proposed earlier, physiological measures (i.e., blood lactate) need to be taken into account in future studies to clarify these issues.

The choice of the relaxation techniques that were implemented in the present experiment was based on the findings of a study on the usage of psychological-based relaxation in sports by Kudlackova et al. (2013). They found that PMR, yoga, hypnosis, systematic breathing, autogenic training, and short naps were the most frequently mentioned strategies. Based on a small number of studies, these techniques displayed the potential to acutely influence physical performance (e.g., Dolbier & Rush, 2012; Donohue et al., 2006; Kim & Tennant, 1993). The final selection of procedures, was examined for their economical nature, i.e., was the literature on orientation (muscle-to-mind vs. mind-to-muscle), duration (effectiveness of one session vs. multiple sessions; length of a single session) and reported effects (effectiveness in related performance areas) consistent with the setting. Reported effects include e.g., a parasympathetic nervous system activity increase and lowered sympathetic activity after systematic breathing (Gosselink, 2003; Holland et al., 2012) and potentially increased energy supply through appropriate cortisol distributions during and after power napping (Waterhouse et al., 2007). Following this structure all involved techniques had the same theoretical basement.

6.1.3 Effects of a disturbed break

Having discussed the effects of improved breaks, especially through administering relaxation techniques, it was concluded that performance can benefit from adequately organised breaks. Breaks in general are a part of almost every sport. However, the consequences of an interruption of these breaks have not been a topic of interest yet. The aim of Manuscript 5.3 was to examine whether an interruption of a recovery break negatively influences subsequent sports performance acutely. It was also assessed if those interruptions affected the subjective perception of a recovery break and the subjective evaluation of one’s own recovery/stress state (see Manuscript 5.3).

25 Discussion

Effects on performance and psychophysiology

The results of Manuscript 5.3 indicate that short interruptions are noticed and that the likeability (appreciation) of a relaxation technique is influenced by them. In accordance to the fact that participants evaluated interrupted recovery sessions as being less pleasant, the interruptions also led to a higher peak heart rate in the participants. Negative performance outcomes though were not an immediate consequence of it.

In theory and practise, interruptions of vulnerable situations such as recovery breaks, are an inherent part of competitive sports (Anshel & Kaissidis, 1997). Considering performance, consequences include reductions in one’s mental preparedness to perform (e.g., reduced information processing capability), less risk-taking behaviour, poorer ability to focus attention on relevant aspects of the situation and making rapid decisions (Anshel, 1990), and increased muscular tension while reducing motor coordination (Anshel, Brown, & Brown, 1993). These consequences are closer related to more complex tasks and therefore might not have affected the repeated sprinting task of Manuscript 5.3.

However, even though, no acute negative effects on performance were found, interruptions should be prevented as thoroughly as possible. Research in related fields in sport psychology found that environmental and situational influences have a big impact on the disruption of for example, the flow state (Jackson, 1995). Jackson (1995) yielded that mechanical failure or environmental distractions were two of the most relevant factors for disrupting a flow state. Additionally, distractions, such as unfavourable conditions, or sudden noises, would disrupt flow for some athletes. Similar to relaxation, individual responses to those factors need to be acknowledged. Jackson (1995) reported anecdotal evidence for that, as unwanted crowd response was too much crowd noise for one athlete and not enough crowd response for another. All these factors could possibly affect recovery breaks and subsequent performance as well. As a next step, research should qualitatively assess athlete experiences from the field and identify reasons for disruptions. Following that, research could be adapted according to relevant issues in the field. In organisational contexts, this has already been applied. Fisher (1998) stated that interruptions would be more irritating if they were more frequent, uncontrollable, and the task has been enjoyed.

Even though detrimental consequences for performance are not proven yet, the effects related to disturbed breaks need to be further examined. Changes in the design of the recovery interruption as well as different levels of athletes should be considered in future studies to investigate the issue of disturbed breaks in more detail. Nevertheless, conclusions with greater explanatory

26 Discussion power could have been drawn from Manuscript 5.3 if a control group had been included in the study design. Even though systematic breathing and power naps have been proven more effective than a control group in a previous study (Manuscript 5.2).

Situational and environmental influences

Regarding the sensitivity of recovery breaks towards interruptions, “simple” techniques such as breathing and napping possibly have an advantage over more complex techniques. After an interruption, it might be easier to continue with a simple protocol compared to a more difficult one. Therefore, more complex techniques such as PMR or yoga might have been stronger influenced by an interruption. These techniques might also be more prone to be affected by interruptions as it is assumed that they induce deeper relaxation states (Manuscript 5.2; Smith, 1999). Beyond acute effects on performance, potential long-term effects of disturbed breaks could have a detrimental influence on well-being and performance (Laux et al., 2015). The authors found that acute stress in combination with the occurrence of disturbed breaks may contribute to injury risk. Their study revealed a direct and significant relationship between heightened injury risk and disturbed breaks, following self-reports of professional football players throughout an entire season. Following Laux et al. (2015), breaks have to be monitored as well as training and competition. They concluded that it may even be that the individual perception of recovery in terms of self-reports rather than the objective length of a break is the crucial variable in order to prevent injuries from occurring. Therefore, Laux et al. (2015) and Saw et al. (2017) recommended self-report application. Manuscripts 5.2 and 5.3 underlined the sensitivity of self-reports and consented this approach.

6.2 General discussion and perspective

The three manuscripts of the present dissertation examined different, though closely related, aspects of relaxation techniques in the sports context. Starting with a systematic overview on the current state of research (Manuscript 5.1), methodological inconsistencies/issues but also positive cross-situational effects of relaxation techniques, especially of biofeedback and hypnosis were revealed. Next to these main findings, trends such as the positive results of systematic breathing and yoga have been reported. Followed by this, basic performance-related differences between certain relaxation techniques have been detected in Manuscript 5.2. Systematic breathing and power naps were found to be performance-enhancing for a non-elite sports student sample in a repeated sprint setting. Lastly, in the study related to Manuscript 5.3 it was shown that short interruptions of relaxation techniques (within a recovery break) did not

27 Discussion affect subsequent performance. However, the subjective assessment of the break was impacted by the interruption.

The collective findings from this dissertation have several implications for practitioners and future research. At first, the overall significant positive effect of certain relaxation techniques on sport performance provides a first step to a robust evidence base for the use of these techniques and affords credibility for the profession. Indeed, relaxation techniques (especially systematic breathing and power naps) appear to have a substantial effect on performance and might therefore provide a critical, marginal gain often sought after in athletic performance. To confirm this assumption the transfer from non-elite to elite sports needs to be established. Regarding this issue, it has been argued that interventions conducted in laboratory settings or training settings cannot be considered as a satisfactory evidence base for providing treatments for athletes in competition (Rumbold et al., 2012). However, before testing relaxation techniques in elite sport settings, mechanisms and potential consequences should be examined on a general level. As this was the purpose of this dissertation, the present results provide a nourishing platform for further research and applied practise.

Secondly, despite the universally supported statement that training of relaxation techniques should adopt a long-term practice approach during which several techniques are taught systematically (Beckmann & Elbe, 2015), it has been shown that certain techniques (i.e., systematic breathing and power naps) have an immediate supportive character. However, other techniques (e.g., PMR and yoga) that are based on a more complex structure need to be practiced indeed. Therefore, the aim should always be a sophisticated training approach for those techniques (Petermann & Vaitl, 2014). Long-term training approaches of relaxation techniques further include important effects that have to be considered when thinking about implementing them. Relaxation is highly relevant as means of developing inner balance and general well-being and as a method of self-control (Kellmann & Beckmann, 2014). Even though, individualisation is of crucial importance, regarding systematic breathing and power naps it was found that comparable effects across performers exist. It could therefore be suggested that these techniques can have positive performance effects for a range of athletes.

Thirdly, derived from Manuscripts 5.2 and 5.3, the conclusion could be drawn that the need to apply relaxation techniques could be based on self-reports. The results from both studies indicated sensitive reactions from participants related to induced physical load and recovery. Similar findings were revealed by Kölling et al. (2015), Fullagar et al. (2016), and Hammes et al. (2016). Regarding the deliverance of relaxation techniques, Brown and Fletcher (2017)

28 Discussion suggested that psychosocial interventions were most effective, when delivered by an integrated individual (e.g., a coach). Based on a more matured relationship and established rapport between coaches and athletes the intervention results might benefit. Therefore, when delivering and teaching relaxation techniques, it might be beneficial for practitioners to engage athletes’ coaches to elicit the greatest possible effects.

Perspectives

An area which receives scientific attention in sports is the use of the previously termed “naive” strategies (Petermann & Vaitl, 2014). These, until now not systematically approached strategies could also be a valuable support in recovery settings in sports. For example, compared to systematic relaxation techniques, music is often regarded as a naive strategy, but in the end, it is one of the most popular and attractive strategies. Studies showed effects of music on a variety of performance-related parameters before and during competition (Loizou & Karageoghis, 2015). Considering recovery, physiological changes, while listening to music include an increased parasympathetic drive, leading to reductions in heart rate, respiration rate, and blood pressure (Jones, Tiller, & Karageorghis, 2017). These changes resemble those occurring during relaxation techniques. A first sports-related study on recuperative effects of music in high- intensity setting has recently been published (Jones et al., 2017). The authors found that fast- tempo, positively-valenced music applied during recovery periods elicited a more pleasant experience and thereby made the high-intensity exercise a more pleasant experience. However, it did not affect performance.

Combining music and relaxation techniques seems to be a promising approach as well as combining specific relaxation techniques (Smith, 1999). For example, implementing systematic breathing before a power nap might shorten the time to fall asleep. This could apply to a PMR session before night sleep as well (McCloughan, Hanrahan, Anderson, & Halson, 2015). Lehrer, Carr, Sargunaraj, and Woolfolk (1994) termed this the multiple modality specificity hypothesis. A combination of techniques which involves multiple response patterns (e.g., somatic and cognitive oriented techniques) should have a broader range of effect than more narrowly focused methods. Such combinations could work better for symptoms with complex etiologies (Smith, 1999). For example, competitive anxiety has autonomic, somatic, and cognitive components. Between two runs in downhill skiing, it might respond better to a combination of systematic breathing, meditating, and yoga stretching compared to stretching alone. As mentioned in the introduction, the demands to which athletes are exposed are multidimensional. Consequently, there are more demands to respond to than training and competition. In addition

29 Discussion to these well reported demands, athletes face a unique array of workplace stressors. Those include the pressure of increased public scrutiny through mainstream and social media, limited support networks due to relocation, group dynamics in team sports, and the potential for injuries to end careers prematurely. Organisational demands are an unavoidable aspect of participation in contemporary sport and extend the solely physical challenges (Fletcher et al., 2012). These factors need to be taken into account as well. The athlete who aims for optimal performance and a balanced recovery/stress state needs to identify all issues that have an impact on recovery and stress. These are, training (e.g., Meeusen et al., 2013), general health (e.g., Raysmith & Drew, 2016), personality factors (e.g., Tranaeus, Johnson, Engström, Skillgate, & Werner, 2014), the capability of applying appropriate recovery strategies (e.g., Manuscript 5.1), and lifestyle (e.g., Marioni, van den Hout, Valenzuela, Brayne, & Matthews, 2012).

7 Conclusion

Based on the characteristics of sports performance, whenever dealing with recovery one should keep in mind that it is highly individual (Hecksteden et al., 2016). Whether the recovery process is successful depends on if the chosen methods fit the purpose of recovery (i.e., a response to a cognitive load or a physical load) and the setting (i.e., time and place; immediately between two tasks, within a few hours, or within a few days; Howatson, Leeder, & van Someren, 2016). This process is supposed to be further mediated by how comfortable one feels with the specific relaxation technique. Integrated into Russell, West, Harper, Cook, and Kilduff’s (2014) approach, an example for an applied setting would be the half-time break in different team sports. During these 15 min breaks, relaxation techniques could be applied to enhance short- term recovery and increase focus and alertness for the upcoming second half. Especially, systematic breathing represents a promising method because of its simple application orientation. After players return from the pitch (13 out of 15 min left of the break) they should get three to four minutes (ten minutes left) to apply their own systematic breathing strategy to calm down and to become receptive for the upcoming individual and/or team talks (three to five minutes left). Followed by a short rewarm-up, players should then be prepared for the second half of a match.

Being able to react to or prevent potential consequences of imbalances between certain demands and recovery in sports requires an appreciation of the interconnectivity of all factors contributing to the performance system. The in-practice integration of relaxation techniques, carefully chosen to meet the requirements of the task at hand could be a small but important element in striving for optimal performance. Relaxation techniques should support the recovery

30 Discussion process, respond to contextual cues, and help athletes focus on the necessary aspects of competition or training. While there is a range of relaxation techniques, individuals will respond to them differently and athletes need to find a set of appropriate techniques that suits their unique needs (Petermann & Vaitl, 2014). This implies conscientious selection and consistent training of those strategies.

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