Br J Sports Med 1998;32:39–43 39 A five year physiological case study of an Olympic Br J Sports Med: first published as 10.1136/bjsm.32.1.39 on 1 March 1998. Downloaded from runner A M Jones 4 Abstract VO2MAX and running economy), and the Objective—To study physiological changes maximum running speed attained in a fast caused by long term endurance training in incremental treadmill test5 have also been suc- a world class female distance runner, and cessfully used to predict performance in to compare these changes with alterations distance running events. However, there are in 3000 m running performance. limited data on the changes in these measures Methods—The subject underwent regu- caused by long periods of endurance training lar physiological assessment during the and their longitudinal relations with endurance period 1991–1995. Physiological measures performance, particularly for female athletes. made included body composition, maxi- This paper reports the results of a five year mal oxygen uptake (VO2MAX), running long study of a world class female distance economy, and lactate threshold. In addi- runner. The runner, who was 17 years of age on commencement of the study in 1991, won tion, the running speed at VO2MAX was estimated. Test protocols, laboratory the World Junior cross country championships equipment, and laboratory techniques in 1992, and has since been placed in the first used were the same for each test session. seven runners in the World Championships Results—The 3000 m race performance (3000 m) and the Olympic Games (5000 m). improved by 8% from 1991 to 1993 after Physical and physiological variables deter- mined at regular intervals throughout the study which it stabilised. In contrast, VO2MAX fell from 1991 (73 ml/kg/min) to 1993 (66 included body composition, VO2MAX, lactate ml/kg/min). Submaximal physiological threshold, running economy, estimated run- variables such as lactate threshold (from ning speed at VO2MAX, and maximum running 15.0 to 18.0 km/h) and running economy speed attained in a fast incremental treadmill (from 53 ml/kg/min to 48 ml/kg/min at 16.0 test. These measures were used to provide a km/h) improved over the course of the comprehensive picture of adaptations in the physiology of the runner to training. The study. Despite no increase in VO2MAX, the reduction in the oxygen cost of submaxi- purpose of this study was: (a) to describe the mal running caused the estimated run- physiology of a world class female distance runner; (b) to investigate changes caused by ning speed at VO2MAX to increase from 19.0 http://bjsm.bmj.com/ km/h in 1991 to 20.4 km/h in 1995. long term endurance training in the physiologi- Conclusions—Improvement in 3000 m cal measures listed above and the relations running performance was not caused by between these variables; and (c) to examine how changes in physiological function aVect an increase in VO2MAX. Rather, the exten- sive training programme adopted, to- distance running performance. gether perhaps with physical maturation, resulted in improvements in submaximal Methods fitness factors such as running economy The study received approval from the Chelsea on October 1, 2021 by guest. Protected copyright. and lactate threshold. These adaptations School ethics committee, University of improved the running speed estimated to Brighton. Thereafter, the subject underwent be associated with VO MAX, and resulted in 2 two physiological assessment sessions per year, improved 3000 m running performance. usually in March–April and November– ( 1998;32:39–43) Br J Sports Med December. To improve confidence that Keywords: distance running; performance; training; changes observed over time were due to real VO2MAX; running economy physiological changes and not to the combined eVect of diurnal biological variability and tech- nical or measurement error, the results of these Department of Exercise and Sport Traditionally, maximal oxygen uptake two test sessions were averaged for each year of Science, Crewe and (VO2MAX) was considered to be the most study. Exactly the same procedures and equip- Alsager Faculty, the important physiological measure in the assess- ment were used for each test session, and the Manchester ment of potential for endurance exercise.1 tests commenced at the same time of day Metropolitan More recently, it has been acknowledged that (10–11 am). The subject was instructed to University, Hassall factors such as the lactate threshold, defined as train only lightly in the 48 hours preceding a Road, Alsager ST7 2HL, United Kingdom the submaximal running speed that invokes a test session, and to arrive at the laboratory in a A M Jones sudden and sustained increase in blood lactate fully hydrated state, at least two hours after concentration,2 and the running economy, eating. After she had given written informed Correspondence to: defined as the energy cost (VO2) of submaximal consent, the subject’s height and body mass Dr A M Jones. running,3 also contribute to endurance run- were measured, and the sum of four skinfolds Accepted for publication ning performance. The estimated running was taken to provide an estimate of body 6 9 October 1997 speed at VO2MAX (a composite measure of composition. 40 Jones Table 1 Changes in various physical and physiological measures over five years of 600 Br J Sports Med: first published as 10.1136/bjsm.32.1.39 on 1 March 1998. Downloaded from endurance training 563 531 520 517 1991 1992 1993 1994 1995 500 Body mass (kg) 51.3 52.2 53.0 54.4 52.5 Body fat (%) 15.7 13.4 11.8 15.7 14.1 Lactate threshold (km/h) 15.0 16.5 17.0 18.0 18.0 [Lactate] at 17 km/h (mM) 3.7 2.8 1.6 1.6 1.4 400 Maximum speed (km/h) 19.5 21.0 22.5 22.0 22.0 For all treadmill testing, the treadmill grade 300 Best 3000 m time (seconds) 1991 1992 1993 1994 1995 was set at 1%.7 The test session was divided Year into two parts. In the first part, the subject per- formed seven to nine submaximal exercise Figure 1 Improvement in best time from 1991 to 1995. The subject was injured in 1994. stages of three minutes duration. Running speeds selected were in the range of 14.0–19.0 80 km/h, and running speed was increased by 0.5 72.8 km/h between stages. During the last minute of 68.5 each stage, expired air was collected in a 70 67 66 66.7 Douglas bag. Heart rate was determined throughout the test by telemetry (Polar Elec- (ml/kg/min) 60 tro, Kempele, Finland), and was recorded at MAX 2 the completion of each stage. A 20 µl fingertip O V capillary blood sample was taken during a 20 50 second break between stages for duplicate 1991 1992 1993 1994 1995 determination of whole blood lactate concen- Year tration by micro-assay (Analox GM7 Hammer- Figure 2 Changes in maximum oxygen uptake (VO2MAX) smith, UK). The coeYcient of variation for from 1991 to 1995. blood lactate determination was 2.8% for ten speed was defined as the running speed samples in the physiological range (5 mM). attained in the final completed stage. When the blood lactate concentration deter- mined for the penultimate submaximal stage exceeded 4 mM, the treadmill speed was kept Results constant and the treadmill grade was increased Over the period of study, the subject gained 6 by 1% each minute until volitional exhaustion. cm in stature (1.68–1.74 m). Body mass During this period, expired air was collected in increased slightly and percentage body fat var- Douglas bags over the final 45 seconds of each ied between 11.8 and 15.7% (table 1). Figure 1 shows the subject’s 8% improve- one minute stage for determination of VO MAX. 2 ment in 3000 m race time (her specialist This procedure has been shown to provide a 8 distance) from 1991 to 1995. The subject did valid assessment of VO MAX. http://bjsm.bmj.com/ 2 not compete in 1994 because of injury. This For determination of respiratory gas ex- improvement in the performance criterion is in change variables, expired air was analysed for contrast with a 9% reduction in VO MAX, from the concentrations of O and CO by sampling 2 2 2 72.8 to 66.0 ml/kg/min, observed over the same through a paramagnetic transducer (Servomex period (fig 2). Maximal heart rate fell from 203 Series 1100, Crowborough, Sussex, UK) and beats/minute in 1991 to 197 beats/minute in an infrared analyser (Servomex, model 1490) 1995. respectively. Volumes were determined by Of the submaximal measures, there was a using a dry gas meter (Harvard Ltd, Eden- marked reduction in the blood lactate concen- on October 1, 2021 by guest. Protected copyright. bridge, Kent, UK). tration measured at a reference submaximal O MAX O V 2 was considered to be the highest V 2 running speed and a 20% improvement in lac- recorded during part one of the test session. tate threshold over the period of study (table The lactate threshold was determined as a clear 1). Further, there was an 11% reduction in the threshold increase in blood lactate from plots VO2 required to run at 16 km/h—that is, an of blood lactate against running speed. Run- improved running economy—between 1992 ning economy was defined as the VO2 required and 1995 (fig 3). Note that a running economy to run at 16.0 km/h.3 The running speed at measure for 1991 is omitted since, in that year, VO2MAX was estimated by solving the regression the lactate threshold was lower than 16.0 km/h.