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 economy), and the Objective—To study physiological changes maximum running speed attained in a fast caused by long term 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 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, , 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 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. equation relating VO2 to running speed (run- The improved running economy over the 4 ning speed=m(VO2)+c)forVO2MAX. The entire submaximal range oVset the lack of regression equation was derived only from data improvement in VO2MAX insofar as the esti-

collected at running speeds below the lactate mated running speed at VO2MAX improved from threshold, since the kinetics of VO2 are consid- 19.0 km/h in 1991 to 20.4 km/h in 1995 (fig 4).

erably more complex above this exercise The estimated running speed at VO2MAX closely intensity.9 predicted the season’s best running speed for After two hours recovery, the subject per- 3000 m. The maximum speed attained in the formed the second part of the test session. She fast incremental treadmill test reflected the began running at 12 km/h, and running speed overall improvement in aerobic fitness up to was increased by 0.5 km/h on the completion of 1993, but was not sensitive to improvement in successive 200 m intervals until volitional the performance criterion later in the study exhaustion was reached.10 Maximum running period (table 1). Physiology of an Olympic runner 41

60 tests performed in each year were averaged. (3) The day to day coeYcient of variation in VO 53 2 51 50.6 determination using the expired gas collection 50 47.6 and analysis system in the exercise laboratory used has been reported to be 2.1%.13

It has been suggested that absolute VO2MAX

(ml/kg/min) 40 2 peaks at about 15 years of age in the sedentary O

V female and that subsequent reduction in

VO2MAX is partly the result of a decline in maxi- 30 14 1991 1992 1993 1994 1995 mum heart rate with age. The 9% reduction

Year in VO2MAX between 1991 and 1993 coincided with a 2% reduction in maximum heart rate Figure 3 Reduced oxygen cost of submaximal running—that is, improved running economy—from 1992 (from 203 to 199 beats/minute). Interpretation to 1995. Data presented are for 16 km/h and 1% treadmill of the longitudinal physiological changes ob- grade. served and their relation to long term endur- ance training is, however, further complicated 22 by the physical growth and maturation of the 20.3 20.4 subject. There is no evidence to suggest that

(km/h) 20 20 19.5 the subject’s 6 cm gain in stature over the

MAX 19 period of study would adversely aVect 2 15 O VO2MAX. However, if increased height was 18 mediated by an increase in leg length, then some change in running economy and maxi- mum running speed might be hypothesised.

Speed at V 16 1991 1992 1993 1994 1995 Information on relative changes in the length of Year body segments is not available, but cross sectional studies have shown no clear relation Figure 4 Improvement in the estimated running speed at between leg length and stride length, or stride maximum oxygen uptake (VO MAX) from 1991 to 1995. 2 length and running economy.16 It is likely, Discussion though, that a gain in lean tissue mass, possibly The purpose of this study was to investigate including bone mass and “non-propulsive” changes in physiological variables induced by muscle mass, was responsible for some of the

long term endurance training in a world class reduction in VO2MAX between 1991 and 1993 female distance runner, and to study, longitu- since body mass increased by 1.7 kg and the dinally, the influence of these variables on an estimated percentage body fat decreased in this endurance performance criterion. period (table 1). There was a substantial improvement in Running economy improved over the course 3000 m race performance over the course of of the study period (fig 3). Although fig 3

the study, with the subject’s best times for the presents VO2 data for 16 km/h, running season being consistently ranked amongst the economy improved over the entire submaximal http://bjsm.bmj.com/ best in the world for that year. The lack of range measured (14.0–18.0 km/h) with train- improvement in the 3000 m performance ing. An association between improved per- criterion in 1995 coincided with the introduc- formance and improved running economy is tion of the 5000 m event for women in major not unexpected. It has been shown that championships, and reflects altered priorities running economy can discriminate perform- and a reduced competitive opportunity at 3000 ance capability in groups of subjects who are 3 m. It is interesting to compare changes in homogeneous for VO2MAX, and that subjects maximal and submaximal physiological vari- with good running economy can frequently on October 1, 2021 by guest. Protected copyright.

ables with the improvement in race perform- outperform subjects with higher VO2MAX ance. Limited data are available on the values.17 In one of the few previously reported physiological status of elite female distance longitudinal case studies involving elite run- 18 runners, but the VO2MAX of 67–73 ml/kg/min ners, Conley et al reported improved running

consistently recorded in the present subject is economy without improvement in VO2MAX after similar to or slightly higher than the 65–70 training in the miler, Steve Scott. The factors ml/kg/min proposed as typical for senior inter- involved in the determination of running nationals by Neumann.11 Figure 2 suggests that economy remain unclear, but both bio-

VO2MAX fell from 1991 to 1993 after which it mechanical factors involved in running style

stabilised. While variability in VO2MAX assess- and physiological factors are probably in- ment (including both technical error and diur- volved. It has been suggested that a greater nal biological variability) has been suggested to relative reliance on the á-glycerophosphate be of the order of 4–5%,12 there are several rea- shuttle over the malate-aspartate shuttle in type sons which point to the trend for the reduction II muscle may reduce the P:O ratio in the type 19 and subsequent stabilisation of VO2MAX to be II fibre compared with the type I fibre. This

real, and not an artefact of the variability in would predict a greater VO2 for any given ATP data collection or analysis. These reasons resynthesis rate in type II muscle. A delayed include the following. (1) The subject was recruitment of type II motor units, as might highly motivated and the exercise test techni- result from the greater oxidative capacity of cians were satisfied that the subject ran to muscle seen with endurance training,20 would

complete exhaustion on each occasion that reduce the VO2 required to run at given

VO2MAX was measured. (2) Data from the two submaximal speeds. Further, it has been 42 Jones

reported that transformation of muscle fibre The sensitivity of lactate threshold to endur- types from type IIb to type IIa,21 and from type ance training is well documented,33 and the Br J Sports Med: first published as 10.1136/bjsm.32.1.39 on 1 March 1998. Downloaded from IIa to type I,22 can occur with extensive endur- running speed at which lactate threshold ance training. A greater proportion of type I occurs has been shown to dictate the speed that fibres in the musculature has been reported to can be sustained during distance running reduce the energetic cost of treadmill races.234 The running speed at which lactate running.23 threshold occurred increased from approxi- Whatever the cause, the reduced oxygen cost mately six minutes and 25 seconds per mile in of running throughout the range of submaxi- 1991 to five minutes and 20 seconds per mile in mal exercise was fundamental in increasing the 1995. This represents a 20% improvement in 4 estimated running speed at VO2MAX over time, the running speed at lactate threshold in four since VO2MAX was essentially unaltered after years, and is indicative of a greatly enhanced 1993. The substitution of VO2MAX by the run- endurance capacity. The exercise intensity ning speed at VO2MAX, involving the interplay of associated with lactate threshold increased VO2MAX and running economy, has been shown from approximately 80% VO2MAX in 1991 to to be highly predictive of success in distance 88% VO MAX in 1995. The importance of a 4 2 running events. In the present study, the esti- high lactate threshold to the performance of O MAX mated running speed at V 2 was a close the fast aerobic events of 3000 m and 5000 m approximation of the best running speed main- is underlined by data demonstrating that time tained for 3000 m during the season. This sup- to exhaustion at VO MAX is positively related ports work suggesting that 3000 m running 2 to the percentage VO2MAX at which lactate requires the utilisation of approximately 100% 35 24 threshold occurs. Interestingly, the rightward VO MAX. This sensitivity of the estimated run- 2 shift in the heart rate–running speed relation ning speed at VO MAX to training, and its close 2 with training resulted in there being little association with distance running perform- change in the heart rate associated with the ance, supports the suggestion of Morgan 4 et al lactate threshold over time. Of practical that the estimation of running speed at VO MAX 2 interest to athletes and coaches without access may be a useful adjunct in the physiological to laboratory based physiological assessment is assessment of the elite runner. In contrast, the the sensitivity of heart rate at submaximal run- maximum running speed attained in the fast incremental treadmill test (part two of the test ning speeds to training status. For example, the battery) was not sensitive to improvement in heart rate measured at 17.0 km/h fell from 199 athletic performance after 1993. The non- beats/minute to 180 beats/minute over the steady state nature of the test protocol9 and the course of the study. Routine measurement of associated requirements for a large contribu- heart rate response to several treadmill running tion of anaerobic processes to ATP resynthesis, speeds might prove useful to the coach in and for skill in high speed running, may assessing the eYcacy of endurance training obscure the measurement of improvement in prescriptions over time. aerobic fitness by such tests. While specific details relating to training are Other changes in physiological variables not available, in general, the development of http://bjsm.bmj.com/ included an elevation of the lactate threshold the training programme reflected the transition and a reduction in the heart rate and the blood of the subject from promising junior to senior lactate concentration measured at international. In later years, particular empha- representative submaximal running speeds sis was placed on the development of a sound (table 1). There is controversy over the nature aerobic “base”, and, to this end, average weekly of the blood lactate response to exercise,25 with training mileage was progressively increased some groups disputing the existence of a from 30–40 miles a week to 70–90 miles a threshold phenomenon.26 27 However, a week. Of interest concerning the physiological on October 1, 2021 by guest. Protected copyright. number of the studies that have described a improvements observed in the present study continuous increase in blood lactate during was the subject’s tendency to perform “steady” incremental exercise may be criticised for using mileage at training intensities close to, or at, protocols that are likely to obscure threshold lactate threshold. This may have been particu- detection—that is, they have used rapid larly important in the development of lactate incremental rates that produce few data points threshold.33 36 The continued improvement in or they have initiated exercise tests at high rela- running economy and lactate threshold might tive intensities. It has been shown that be considered important in the future attain- two-component linear regression analysis— ment of success in the 5000 m and 10 000 m that is, a single threshold model—provides a track events.

closer fit to the blood lactate–VO2 relationship In summary, this study, which is the first to during exercise than does an exponential plus present data on the physiological changes constant model,28 with the exponential model accompanying training in a world class female producing a very poor fit to blood lactate data distance runner over a number of years, in the region of interest (1.0–4.5 mM).29 showed improved 3000 m running perform- Numerous studies testify to the validity and ance without an improvement in maximal oxy- reliability of lactate threshold determination by gen consumption. Submaximal physiological visual inspection,30 31 and the use of multistage variables including running economy and test protocols with stage durations of three to lactate threshold improved considerably, and four minutes, and small intensity increments the lower oxygen cost of running at submaxi- (as in the present study) further simplifies mal speeds was important in increasing the threshold identification.32 running speed estimated to be associated with Physiology of an Olympic runner 43

from humans of diVering physical activity. Acta Physiol VO2MAX. The latter measure was the best Scand 1987;129:505–15. Br J Sports Med: first published as 10.1136/bjsm.32.1.39 on 1 March 1998. Downloaded from predictor of 3000 m running performance. 20 Holloszy JO, Coyle EF. Adaptations of skeletal muscle to endurance exercise and their metabolic consequences. J 1984; :831–8. 1 Saltin B, Astrand PO. Maximal oxygen uptake in athletes. Appl Physiol 56 J 21 Andersen P, Henriksson J. Training induced changes in the Appl Physiol 1967;23:353-358. 2 Kumagai S, Tanaka K, Matsuura Y, et al. Relationships of subgroups of human type II skeletal muscle fibres. Acta the anaerobic threshold with the 5 km, 10 km, and 10 mile Physiol Scand 1977;99:123–5. races. Eur J Appl Physiol 1982;49:15–23. 22 Baumann H, Jaggi M, Soland F, et al. Exercise training 3 Conley DL, Krahenbuhl GS. Running economy and induces transitions of myosin isoform subunits within distance running performance of highly trained athletes. histochemically typed human muscle fibres. Pflugers Arch Med Sci Sports Exerc 1980;12:357–60. 1987;409:349–60. 4 Morgan DW, Baldini FD, Martin PE, Kohrt WM. Ten 23 Bosco C, Montanari G, Ribacchi R, et al. Relationship kilometer performance and predicted velocity at VO2 max between the eYciency of muscular work during jumping among well-trained male runners. Med Sci Sports Exerc and the energetics of running. Eur J Appl Physiol 1987;56: 1989;21:78–83. 138–43. 5 Noakes TD, Myburgh KH, Schall R. Peak treadmill velocity 24 Leger L, Mercier D, Gauvin L. The relationship between % during the VO max test predicts running performance. 2 J VO2 max and running performance time. In: Landers DM, Sports Sci 1990;8:35–45. ed. Sport and elite performers. Champaign, IL: Human 6 Durnin JVGA, Womersley J. Body fat assessed from total Kinetics, 1986:113–19. body density and its estimation from skinfold thickness: 25 Morton RH. Comment on “Ventilation and blood lactate measurements on 481 men and women aged from 16 to 72 increase exponentially during incremental exercise”. J years. Brit J Nutr 1974;32:77–97. Sports Sci 1993;11:371–5. 7 Jones AM, Doust JH. A 1 % treadmill grade most accurately 26 Dennis SC, Noakes TD, Bosch AN. Ventilation and blood reflects the energetic cost of outdoor running. J Sports Sci lactate increase exponentially during incremental exercise. 1996;14:321–7. 8 Jones AM, Doust JH. A comparison of three treadmill pro- J Sports Sci 1992;10:437–49. tocols for the determination of maximal aerobic power in 27 Hughson RL, Weisiger KH, Swanson GD. Blood lactate runners. J Sports Sci 1996;14:89. concentration increases as a continuous function in 9 Poole DC, Ward SA, Gardner GW, Whipp BJ. Metabolic progressive exercise. J Appl Physiol 1987;62:1975–81. and respiratory profile of the upper limit for prolonged 28 Beaver WL, Wasserman K, Whipp BJ. Improved detection exercise in man. Ergonomics 1988;31:1265–79. of lactate threshold during exercise using a log-log 10 Conconi F, Ferrari M, Ziglio PG, et al. Determination of the transformation. J Appl Physiol 1985;59:1936–40. anaerobic threshold by a noninvasive field test in runners. J 29 Wasserman K, Beaver WL, Whipp BJ. Gas exchange theory Appl Physiol 1982;52:869-73. and the lactic acidosis (anaerobic) threshold. Circulation 11 Neumann G. Special performance capacity. In Dirix A, 1990;81(Suppl II):14–30. Knuttgen HG, Tittel K, eds. The Olympic book of sports 30 Davis JA, Vodak P, Wilmore JH, et al. Anaerobic threshold medicine, vol 1. Oxford: Blackwell Scientific Publications, and maximal aerobic power for three modes of exercise. J 1988. Appl Physiol 1976;41:544–50. 12 Katch VL, Sady SS, Freedson P. Biological variability in 31 Yoshida T, Nagata A, Muro M, et al. The validity of anaero- maximum aerobic power. Med Sci Sports Exerc 1982;14:21– bic threshold determination by a Douglas bag method 5. compared with arterial blood lactate concentration. Eur J 13 James DV, Doust JH. Reliability of pulmonary VO 2 Appl Physiol 1981;46:423–30. measurement and implications for determination of recov- 32 Weltman A, Snead D, Steim P, et al. Reliability and validity ery from running. J Sports Sci 1997;15:30. of a continuous incremental treadmill protocol for the 14 Krahenbuhl GS, Skinner JS, Kohrt WM. Developmental determination of lactate threshold, fixed blood lactate con- aspects of maximal aerobic power in children. Exerc Sport centrations, and VO max. 1990;11:26–32. 1985;14:503–38. 2 Int J Sports Med Sci Rev 33 Londeree BR. E ect of training on lactate/ventilatory 15 Astrand PO, Rodahl K. Textbook of work physiology, 3rd ed. V New York: McGraw-Hill,1986: 330–8, 396–8. thresholds: a meta-analysis. Med Sci Sports Exerc 1997;29: 16 Cavanagh PR, Kram R. Stride length in distance running: 837–43. velocity, body dimensions and added mass eVects. In Cav- 34 Fay L, Londeree BR, Lafontaine TP, Volek MR. Physiologi- anagh PR, ed. Biomechanics of distance running. Champaign: cal parameters related to distance running performance in Human Kinetics, 1990:35–63. female athletes. Med Sci Sports Exerc 1989;21:319-24. 17 Daniels JT. A physiologist’s view of running economy. Med 35 Billat V, Renoux J, Pinoteau J, et al. Reproducibility of run- Sci Sports Exerc 1985;17:332–8. ning time to exhaustion at VO2 max in sub-elite runners. 18 Conley DL, Krahenbuhl GS, Burkett LN, Millar AL. Med Sci Sports Exerc 1994;26:254-7. 36 Henritze J, Weltman A, Schurrer RL, Barlow K. E ects of Following Steve Scott: physiological changes accompany- V http://bjsm.bmj.com/ ing training. Physician and Sports Medicine 1984;12:103–6. training at and above the lactate threshold on the lactate 19 Schantz PG, Henriksson J. Enzyme levels of the NADH threshold and maximal oxygen uptake. Eur J Appl Physiol shuttle systems: measurements in isolated muscle fibres 1985;54:84–8.

Commentary

This is a longitudinal study of an athlete’s maturation to elite status, the kind of topic more often tackled anecdotally in the coaching literature than on the basis of scientific tests, as it is here. So I find Andrew Jones’ paper both interesting and valuable. on October 1, 2021 by guest. Protected copyright. The athlete was only 17 when the study began. Consequently, the eVects of training cannot be separated cleanly from those of the last stages of growth. Nonetheless, perhaps the most power-

ful finding, which is that VO2MAX, although extremely high throughout, actually falls a few percent while performance improves by a similar margin, makes its point irrespective of whether training or maturation was the main factor in the improvement. The laboratory tests that do correlate well with track performance are those of lactate threshold, running economy, and estimated speed at

VO2MAX. These findings nicely confirm results from several cross sectional studies of recent years. NEIL SPURWAY