The 3-min Test Does not Provide a Valid Measure of Critical Power Using the SRM Isokinetic Mode

Abstract

Recent datas suggest that the mean power over the final 30 s of a 3-min all-out test is equivalent to Critical Power (CP) using the linear ergometer mode. The purpose of the present study was to identify whether this is also true using an “isokinetic mode”. 13 cyclists performed: 1) a ramp test; 2) three 3-min all-out trials to establish End Power (EP) and work done above EP (WEP); and 3) 3 constant work rate trials to determine CP and the work done above CP (W′) using the work-time (=CP1/W′1) and 1/time (=CP2/W′2) models. Coefficient of variation in EP was 4.45% between trials 1 and 2, and 4.29% between trials 2 and 3. Limits of Agreement for trials 1–2 and trials 2–3 were −2±38 W. Significant differences were observed between EP and CP1 (+37 W, P<0.001), between WEP and W′1(−6.2 kJ, P=0.001), between EP and CP2 (+31 W, P<0.001) and between WEP and W′2 (−4.2 kJ, P=0.006). Average SEE values for EP-CP1 and EP-CP2 of 7.1% and 6.6% respectively were identified. Data suggest that using an isokinetic mode 3-min all-out test, while yielding a reliable measure of EP, does not provide a valid measure of CP.

Key words

critical intensity - exercise testing - anaerobic work capacity - reliability - validity

• References

• 1 Atkinson G, Nevill AM. Statistical methods for assessing measurement error (reliability) in variables relevant to sports medicine. Sports Med 1998; 26: 217-238
• 2 Barker AR, Bond B, Toman C, Williams CA, Armstrong N. Critical power in adolescents: physiological bases and assessment using all-out exercise. Eur J Appl Physiol 2012; 112: 1359-1370
• 3 Barker T, Poole DC, Noble ML, Barstow TJ. Human critical power-oxygen uptake relationship at different pedalling frequencies. Exp Physiol 2006; 91: 621-632
• 4 Bergstrom H, Housh T. A new single work bout test to estimate critical power and anaerobic work capacity. J Strength Cond Res 2012; 26: 656-663
• 5 Bergstrom H, Housh TJ, Zuniga JM, Camic CL, Traylor DA, Lewis RW, Schmidt RJ, Johnson GO. Estimates of critical power and anaerobic work capacity from a single, all-out test of less than 3-min. J Sport Med Doping Stud 2012; 2: 1-5
• 6 Blair SN, Painter P, Pate R, Pate R, Smith K, Taylor C. Resource manual for Guidelines for exercise testing and prescription. Philadelphia: Lea & Febiger; 1988: 414-420
• 7 Bland JM, Altman DG. Statistical methods for assessing agreement between two methods of clinical measurement. Lancet 1986; 1: 307-310
• 8 Brickley G, Dekerle J, Hammond AJ, Pringle J, Carter H. Assessment of maximal aerobic power and critical power in a single 90-s isokinetic all-out cycling test. Int J Sports Med 2007; 28: 414-419
• 9 Burnley M, Doust JH, Vanhatalo A. A 3-min all-out test to determine peak oxygen uptake and the maximal steady state. Med Sci Sports Exerc 2006; 38: 1995-2003
• 10 Busso T, Gimenez P, Chatagnon M. A comparison of modelling procedures used to estimate the power-exhaustion time relationship. Eur J Appl Physiol 2010; 108: 257-263
• 11 Carnevale TJ, Gaesser GA. Effects of pedaling speed on the power-duration relationship for high-intensity exercise. Med Sci Sports Exerc 1991; 23: 242-246
• 12 Cheng CF, Yang YS, Lin HM, Lee CL, Wang CY. Determination of critical power in trained rowers using a three-minute all-out rowing test. Eur J Appl Physiol 2012; 112: 1251-1260
• 13 Dekerle J, Brickley G, Hammond AJP, Pringle JSM, Carter H. Validity of the two-parameter model in estimating the anaerobic work capacity. Eur J Appl Physiol 2006; 96: 257-264
• 14 Dekerle J, Vanhatalo A, Burnley M. Determination of critical power from a single test. Sci Sports 2008; 23: 231-238
• 15 Dekerle J, Williams C, McGawley K, Carter H. Critical power is not attained at the end of an isokinetic 90-second all-out test in children. J Sports Sci 2009; 27: 379-385
• 16 Francis JT, Quinn TJ, Amann M, LaRoche DP. Defining intensity domains from the end power of a 3-min all-out cycling test. Med Sci Sports Exerc 2010; 42: 1769-1775
• 17 Gaesser GA, Wilson LA. Effects of continuous and interval training on the parameters of the power-endurance time relationship for high-intensity exercise. Int J Sports Med 1988; 9: 417-421
• 18 Gastin PB, Costill DL, Lawson DL, Krzeminski K, McConell GK. Accumulated oxygen deficit during supramaximal all-out and constant intensity exercise. Med Sci Sports Exerc 1995; 27: 255-263
• 19 Gastin PB, Lawson DL. Variable resistance all-out test to generate accumulated oxygen deficit and predict anaerobic capacity. Eur J Appl Physiol 1994; 69: 331-336
• 20 Harriss DJ, Atkinson G. Update – Ethical standards in sport and exercise science research. Int J Sports Med 2011; 32: 819-821
• 21 Hill D, Poole DCSJ. The relationship between power and the time to achieve VO2max. Med Sci Sports Exerc 2002; 34: 709-714
• 22 Hill DW. The critical power concept. A review. Sports Med 1993; 16: 237-254
• 23 Hopkins WG. A new view on statistics. Internet Society for Sport Science 2000. Available at: http://www.sportsci.org/resource/stats/ Accessed 15 November 2012
• 24 Johnson TM, Sexton PJ, Placek AM, Murray SR, Pettitt RW. Reliability analysis of the 3-min all-out exercise test for cycle ergometry. Med Sci Sports Exerc 2011; 43: 2375-2380
• 25 Jones AM, Vanhatalo A, Burnley M, Morton RH, Poole DC. Critical power: implications for determination of VO2max and exercise tolerance. Med Sci Sports Exerc 2010; 42: 1876-1890
• 26 Parker Simpson L, Jones AM, Vanhatalo A, Wilkerson DP. Influence of initial metabolic rate on the power-duration relationship for all-out exercise. Eur J Appl Physiol 2012; 112: 2467-2473
• 27 Passfield L, Jobson SA, Atkinson G, Barton G, Scarf P. Longitudinal changes in weighted indices of work-rate but not average power output of cyclists during a racing season [abstract]. J Sports Sci 2009; 27: S102-S103
• 28 Paton C, Hopkins W. Variation in performance of elite cyclists from race to race. Eur J Sport Sci 2006; 6: 25-31
• 29 Poole DC. Resolving the determinants of high-intensity exercise performance. Exp Physiol 2009; 94: 197-198
• 30 Vanhatalo A, Doust JH, Burnley M. Determination of critical power using a 3-min all-out cycling test. Med Sci Sports Exerc 2007; 39: 548-555
• 31 Vanhatalo A, Doust JH, Burnley M. Robustness of a 3 min all-out cycling test to manipulations of power profile and cadence in humans. Exp Physiol 2008; 93: 383-390
• 32 Vanhatalo A, Jones AM. Influence of creatine supplementation on the parameters of the “all-out critical power test”. J Exerc Sci Fit 2009; 7: 9-17
• 33 Withers RT, Ploeg G, Finn JP. Oxygen deficits incurred during 45, 60, 75 and 90-s maximal cycling on an air-braked ergometer. Eur J Appl Physiol 1993; 67: 185-191