Prediction of triathlon race time from laboratory testing in national triathletes

Purpose: Four days after competing in an Olympic-distance National Triathlo n Championship (1500-m swim, 40-km cycle, 10-km run), five male and five fe male triathletes underwent comprehensive physiological testing in an attemp t to determine which physiological variables accurately predict triathlon r ace time. Methods: All triathletes underwent maximal swimming tests over 25 and 400 m, the determination of peak sustained power output (PPO) and peak oxygen uptake ((V) over dotO(2peak)) during an incremental cycle test to e xhaustion, and a maximal treadmill running test to assess peak running velo city and (V) over dotO(2peak). In addition, submaximal steady-state measure s of oxygen uptake ((V) over dotO(2)), blood [lactate], and heart rate (HR) were determined during the cycling and running tests. Results: The five mo st significant (P < 0.01) predictors of triathlon performance were blood la ctate measured during steady-state cycling at a workload of 4 W.kg(-1) body mass (BM) (r = 0.92), blood lactate while running at 15 km.h(-1) (r = 0.89 ), PPO (r = 0.86), peak treadmill running velocity (r = 0.85), and (V) over dotO(2peak) during cycling (r = 0.85). Stepwise multiple regression analys is revealed a highly significant (r = 0.90, P < 0.001) relationship between predicted race time (from laboratory measures) and actual race time, from the following calculation: race time (s) = -129 (peak treadmill velocity [k m.h(-1)]) + 122 ([lactate] at 4 W.kg(-1) BM) + 9456. Conclusion: The result s of this study show that race time for top triathletes competing over the Olympic distance can be accurately predicted from the results of maximal an d submaximal laboratory measures.