Download PDF
Int J Sports Med 2019; 40(10): 631-638
DOI: 10.1055/a-0946-1974
Training & Testing
© Georg Thieme Verlag KG Stuttgart · New York

Maximal Sustained Isokinetic Power at Exercise Intolerance is not Critical Power

Stanley Yong‡
1   School of Exercise & Nutritional Sciences, San Diego State University, San Diego, United States
,
Austin R. Swisher‡
1   School of Exercise & Nutritional Sciences, San Diego State University, San Diego, United States
,
Carrie Ferguson
2   School of Biomedical Sciences, University of Leeds, Leeds, United Kingdom of Great Britain and Northern Ireland
,
Daniel T. Cannon
1   School of Exercise & Nutritional Sciences, San Diego State University, San Diego, United States
› Author Affiliations
Further Information

Publication History



accepted 28 May 2019

Publication Date:
31 July 2019 (online)

Also available at
    Permissions and Reprints

Abstract

The asymptote of the hyperbolic power-duration relationship, critical power (CP), demarcates sustainable from non-sustainable exercise. CP is a salient parameter within the theoretical framework determining exercise tolerance. However, measuring CP is time consuming – typically 4 constant-power exercise tests to intolerance, or a 3-min all-out sprint is required.

To determine whether 30 s of maximal isokinetic cycling, immediately following the limit of tolerance, approximates CP.

Fifteen participants (7 women, 8 men, 23±5 yr, 71±12 kg, V̇O2peak 4.39±1.04 L·min−1; 61±9 mL·kg·min−1) completed 4 constant supra-CP exercise tests to intolerance. Each test was followed immediately by a 30 s maximal isokinetic effort at 80 rpm. Mean isokinetic power was compared to the known CP.

Mean±SD CP was 159±47 W (CI95 133, 185 W). Maximal isokinetic power immediately following intolerance was greater (p<0.05) than CP in all but one comparison (181±51 vs. 159±47 W; p>0.07). However, this closest estimation, following the longest duration constant-power test, resulted in 21 W of mean bias and wide limits of agreement (±84 W).

Isokinetic power measured immediately following intolerance consistently overestimated critical power. Thus, an adjunct of 30 s maximal isokinetic cycling immediately following the limit of tolerance does not approximate critical power.

Key words

isokinetic - cycling - fatigue

equal contribution


 

  • References

  • 1 Hill AV. The physiological basis of athletic records. Nature 1925; 118: 544-548
    PubMedGoogle Scholar
  • 2 Poole DC, Burnley M, Vanhatalo A, Rossiter HB, Jones AM. Critical power: an important fatigue threshold in exercise physiology. Med Sci Sports Exerc 2016; 48: 2320-2334
    CrossrefPubMedGoogle Scholar
  • 3 Whipp BJ. Domains of aerobic function and their limiting parameters. In Steinacker JM, Ward SA. (ed.). The physiology and pathophysiology of Exercise Tolerance. New York: Plenum; 1996: 83-89
    CrossrefGoogle Scholar
  • 4 Myers J, Prakash M, Froelicher V, Do D, Partington S, Atwood JE. Exercise capacity and mortality among men referred for exercise testing. N Engl J Med 2002; 346: 793-801
    CrossrefPubMedGoogle Scholar
  • 5 Paffenbarger Jr. RS, Hyde RT, Wing AL, Hsieh CC. Physical activity, all-cause mortality, and longevity of college alumni. N Engl J Med 1986; 314: 605-613
    CrossrefPubMedGoogle Scholar
  • 6 Paffenbarger Jr. RS, Hyde RT, Wing AL, Lee IM, Jung DL, Kampert JB. The association of changes in physical-activity level and other lifestyle characteristics with mortality among men. N Engl J Med 1993; 328: 538-545
    CrossrefPubMedGoogle Scholar
  • 7 Whipp BJ, Ward SA. Quantifying intervention-related improvements in exercise tolerance. Eur Respir J 2009; 33: 1254-1260
    CrossrefPubMedGoogle Scholar
  • 8 Moritani T, Nagata A, deVries HA, Muro M. Critical power as a measure of physical work capacity and anaerobic threshold. Ergonomics 1981; 24: 339-350
    CrossrefPubMedGoogle Scholar
  • 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
    CrossrefPubMedGoogle Scholar
  • 10 Constantini K, Sabapathy S, Cross TJ. A single-session testing protocol to determine critical power and W'. Eur J Appl Physiol 2014; 114: 1153-1161
    CrossrefPubMedGoogle Scholar
  • 11 Dekerle J, Barstow TJ, Regan L, Carter H. The critical power concept in all-out isokinetic exercise. J Sci Med Sport 2014; 17: 640-644
    CrossrefPubMedGoogle Scholar
  • 12 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
    CrossrefPubMedGoogle Scholar
  • 13 Murgatroyd SR, Wylde LA, Cannon DT, Ward SA, Rossiter HBA. 'ramp-sprint' protocol to characterise indices of aerobic function and exercise intensity domains in a single laboratory test. Eur J Appl Physiol 2014; 114: 1863-1874
    CrossrefPubMedGoogle Scholar
  • 14 Chidnok W, Dimenna FJ, Bailey SJ, Wilkerson DP, Vanhatalo A, Jones AM. Effects of pacing strategy on work done above critical power during high-intensity exercise. Med Sci Sports Exerc 2013; 45: 1377-1385
    CrossrefPubMedGoogle Scholar
  • 15 Coats EM, Rossiter HB, Day JR, Miura A, Fukuba Y, Whipp BJ. Intensity-dependent tolerance to exercise after attaining V(O2) max in humans. J Appl Physiol (1985) 2003; 95: 483-490
    CrossrefPubMedGoogle Scholar
  • 16 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
    CrossrefPubMedGoogle Scholar
  • 17 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
    Article in Thieme ConnectPubMedGoogle Scholar
  • 18 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
    CrossrefPubMedGoogle Scholar
  • 19 Barker T, Poole DC, Noble ML, Barstow TJ. Human critical power-oxygen uptake relationship at different pedalling frequencies. Exp Physiol 2006; 91: 621-632
    CrossrefPubMedGoogle Scholar
  • 20 Cannon DT, Coelho AC, Cao R, Cheng A, Porszasz J, Casaburi R, Rossiter HB. Skeletal muscle power and fatigue at the tolerable limit of ramp-incremental exercise in COPD. J Appl Physiol (1985) 2016; 121: 1365-1373
    CrossrefPubMedGoogle Scholar
  • 21 Coelho AC, Cannon DT, Cao R, Porszasz J, Casaburi R, Knorst MM, Rossiter HB. Instantaneous quantification of skeletal muscle activation, power production, and fatigue during cycle ergometry. J Appl Physiol (1985) 2015; 118: 646-654
    CrossrefPubMedGoogle Scholar
  • 22 Ferguson C, Cannon DT, Wylde LA, Benson AP, Rossiter HB. Power-velocity and power-efficiency implications in the limitation of ramp incremental cycle ergometry. J Appl Physiol (1985) 2016; 120: 477-■
    CrossrefPubMedGoogle Scholar
  • 23 Ferguson C, Wylde LA, Benson AP, Cannon DT, Rossiter HB. No reserve in isokinetic cycling power at intolerance during ramp incremental exercise in endurance-trained men. J Appl Physiol (1985) 2016; 120: 70-77
    CrossrefPubMedGoogle Scholar
  • 24 Harriss DJ, Macsween A, Atkinson G. Standards for ethics in sport and exercise science research: 2018 Update. Int J Sports Med 2017; 38: 1126-1131
    Article in Thieme ConnectPubMedGoogle Scholar
  • 25 van der Vaart H, Murgatroyd SR, Rossiter HB, Chen C, Casaburi R, Porszasz J. Selecting constant work rates for endurance testing in copd: the role of the power-duration relationship. COPD 2014; 11: 267-276
    PubMedGoogle Scholar
  • 26 Bland JM, Altman DG. Statistical methods for assessing agreement between two methods of clinical measurement. Lancet 1986; 1: 307-310
    PubMedGoogle Scholar
  • 27 Poole DC, Jones AM. Measurement of the maximum oxygen uptake Vo2max: Vo2peak is no longer acceptable. J Appl Physiol (1985) 2017; 122: 997-1002
    CrossrefPubMedGoogle Scholar
  • 28 Neder JA, Jones PW, Nery LE, Whipp BJ. Determinants of the exercise endurance capacity in patients with chronic obstructive pulmonary disease. The power-duration relationship. Am J Respir Crit Care Med 2000; 162: 497-504
    CrossrefPubMedGoogle Scholar
  • 29 Hodgson MD, Keir DA, Copithorne DB, Rice CL, Kowalchuk JM. Power reserve following ramp-incremental cycling to exhaustion: implications for muscle fatigue and function. J Appl Physiol (1985) 2018; 125: 304-312
    CrossrefPubMedGoogle Scholar
  • 30 Ferguson C, Rossiter HB, Whipp BJ, Cathcart AJ, Murgatroyd SR, Ward SA. Effect of recovery duration from prior exhaustive exercise on the parameters of the power-duration relationship. J Appl Physiol (1985) 2010; 108: 866-874
    CrossrefPubMedGoogle Scholar
  • 31 Skiba PF, Fulford J, Clarke DC, Vanhatalo A, Jones AM. Intramuscular determinants of the ability to recover work capacity above critical power. Eur J Appl Physiol 2015; 115: 703-713
    CrossrefPubMedGoogle Scholar