See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/233855836 Intervals, Thresholds, and Long Slow Distance: the Role of Intensity and Duration in Endurance Training Article · January 2009 CITATIONS READS 117 3,278 2 authors: Stephen Seiler Espen Tønnessen Universitetet i Agder The Norwegian Olympic Sport Center 160 PUBLICATIONS 2,861 CITATIONS 62 PUBLICATIONS 1,033 CITATIONS SEE PROFILE SEE PROFILE Some of the authors of this publication are also working on these related projects: Connecting physiological and perceptual responses during HIIT View project Training intensity, volume and recovery distribution among elite endurance athletes View project All content following this page was uploaded by Espen Tønnessen on 21 May 2014. The user has requested enhancement of the downloaded file. SPORTSCIENCE · sportsci.org Perspectives / Training Intervals, Thresholds, and Long Slow Distance: the Role of Intensity and Duration in Endurance Training Stephen Seiler1 and Espen Tønnessen2 Sportscience 13, 32-53, 2009 (sportsci.org/2009/ss.htm) 1 University of Agder, Faculty of Health and Sport, Kristiansand 4604, Norway. Email. 2 Norwegian Olympic and Paralympic Committee National Training Center, Oslo, Norway. Email. Reviewers: Iñigo Mujika, Araba Sport Clinic, Vitoria, Spain; Stephen Ingham, English Institute of Sport, Loughborough Uni- versity, Leicestershire, LE11 3TU, UK. Endurance training involves manipulation of intensity, duration, and frequency of training sessions. The relative impact of short, high-intensity training versus longer, slower distance training has been studied and debated for decades among athletes, coaches, and scientists. Currently, the popularity pendulum has swung towards high-intensity interval training. Many fitness experts, as well as some scientists, now argue that brief, high-intensity interval work is the only form of training necessary for performance optimization. Research on the impact of interval and continuous training with untrained to moderately trained subjects does not support the current interval craze, but the evidence does suggest that short intense training bouts and longer continuous exercise ses- sions should both be a part of effective endurance training. Elite endurance athletes perform 80 % or more of their training at intensities clearly below their lactate threshold and use high-intensity training surprisingly sparingly. Studies involving intensification of training in already well-trained athletes have shown equivocal results at best. The available evidence suggests that combining large volumes of low-intensity training with careful use of high-intensity interval training throughout the annual training cycle is the best-practice model for de- velopment of endurance performance. KEYWORDS: lactate threshold, maxi- mal oxygen uptake, VO2max, periodization. Reprint pdf · Reprint doc · Reviewer's Commentary Interval Training: a Long History .......................................................................33 Exercise Intensity Zones...................................................................................35 Training Plans and Cellular Signaling...............................................................36 Training Intensities of Elite Endurance Athletes ...............................................38 Units for Training Intensity ................................................................................41 The 80-20 Rule for Intensity..............................................................................42 Training Volume of Elite Athletes......................................................................43 Intensified-Training Studies ..............................................................................44 Intensity for Recreational Athletes ....................................................................46 Case Studies of Training Manipulation .............................................................47 Case 1–From Soccer Pro to Elite Cyclist ...................................................47 Case 2–From Modern Pentathlete to Runner ............................................48 Valid Comparisons of Training Interventions ....................................................49 Conclusions.......................................................................................................49 References........................................................................................................50 The evening before the start of the 2009 defended his dissertation. The other had played European College of Sport Science Congress in the adversarial role of “førsteopponent.” Tøn- Oslo, the two of us were sitting at a doctoral nessen’s research on the talent development dissertation defense dinner that is part of the process included extensive empirical analyses time honored tradition of the “doctoral dispu- of the training characteristics of selected world tas” in Scandinavia. One of us was the relieved champion female endurance athletes. His career disputant (Tønnessen) who had successfully case-study series systematized training diary Sportscience 13, 32-53, 2009 Seiler & Tønnessen: Intensity and Duration in Endurance Training Page 33 logs of over 15,000 training sessions from three broader question of training intensity distribu- World and/or Olympic champions in three tion in competitive endurance athletes. sports: distance running, cross-country skiing, Interval Training: a Long History and orienteering. Common for all three cham- International running coach Peter Thompson pions was that over their long, successful ca- wrote in Athletics Weekly that clear references reers, about 85 % of their training sessions were to “repetition training” were seen already by the performed as continuous efforts at low to mod- early 1900s (Thompson, 2005). Nobel Prize erate intensity (blood lactate ≤2 mM). Among winning physiologist AV Hill incorporated the 40 guests sat coaches, scientists, and former intermittent exercise into his studies of exercis- athletes who had been directly or indirectly ing humans already in the 1920s (Hill et al., involved in winning more endurance sport 1924a; Hill et al., 1924b). About this time, Olympic gold medals and world championships Swede Gosta Holmer introduced Fartlek to than we could count. One guest, Dag Kaas, had distance running (fart= speed and lek= play in coached 12 individual world champions in four Swedish). The specific term interval training is different sports. In his toast to the candidate he attributed to German coach Waldemer Ger- remarked, ”My experience as a coach tells me schler. Influenced by work physiologist Hans that to become world champion in endurance Reindell in the late 1930s, he was convinced disciplines, you have to train SMART, AND you that alternating periods of hard work and recov- have to train a LOT. One without the other is ery was an effective adaptive stimulus for the insufficient.” heart. They apparently adopted the term be- So what is smart endurance training? The cause they both believed that it was the recov- question is timely: research and popular interest ery interval that was vital to the training effect. in interval training for fitness, rehabilitation, Since then, the terms intermittent exercise, and performance has skyrocketed in recent repetition training, and interval training have years on the back of new research studies and all been used to describe a broad range of train- even more marketing by various players in the ing prescriptions involving alternating work and health and fitness industry. Some recent inves- rest periods (Daniels and Scardina, 1984). In tigations on untrained or moderately trained the 1960s, Swedish physiologists, led by Per subjects have suggested that 2-8 wk of 2-3 Åstrand, performed groundbreaking research times weekly intense interval training can in- demonstrating how manipulation of work dura- duce rapid and substantial metabolic and car- tion and rest duration could dramatically impact diovascular performance improvements physiological responses to intermittent exercise (Daussin et al., 2007; Helgerud et al., 2007; (Åstrand et al., 1960; Åstrand I, 1960; Christen- Talanian et al., 2007). Some popular media sen, 1960; Christensen et al., 1960). As Daniels articles have interpreted these findings to mean and Scardina (1984) concluded 25 years ago, that long, steady distance sessions are a waste their work laid the foundation for all interval of time. Whether well founded or not, this in- training research to follow. In their classic terpretation raises reasonable questions about chapter Physical Training in Textbook of Work the importance and quantity of high- (and low-) Physiology, Åstrand and Rodahl (1986) wrote, intensity training in the overall training process “it is an important but unsolved question which of the endurance athlete. Our goal with this type of training is most effective: to maintain a article is to discuss this issue in a way that inte- level representing 90 % of the maximal oxygen grates research and practice. uptake for 40 min, or to tax 100 % of the oxy- In view of the recent hype and the explosion gen uptake capacity for about 16 min.” (The in the number of studies investigating interval same chapter from the 4th edition, published in training in various health, rehabilitation, and 2003, can be read here.) This quote serves as performance settings, one could be forgiven for an appropriate background for defining high assuming that this training