Abstract
The control of pulmonary oxygen uptake \((\dot{{V}}\hbox{O}_{2})\) kinetics above the lactate threshold (LT) is complex and controversial. Above LT, \(\dot{{V}}\hbox{O}_{2}\) for square-wave exercise is greater than predicted from the sub-LT \(\dot{{V}}\hbox{O}_{2}\)–WR relationship, reflecting the contribution of an additional “slow” component \((\dot{{V}}\hbox{O}_{{2}\,\hbox{sc}}).\) Investigators have argued for a contribution to this slow component from the recruitment of fast-twitch muscle fibres, which are less aerobically efficient than slow-twitch fibres. Six healthy subjects performed a rapid-incremental bilateral knee-extension exercise test to the limit of tolerance for the estimation of \(\dot{{V}}\hbox{O}_{{2}\,{\rm peak}},\) ventilatory threshold (VT), and the difference between \(\dot{{V}}\hbox{O}_{{2}{\rm peak}}\) and \(\dot{{V}}\hbox{O}_{2}\) at VT (Δ). Subjects then completed three repetitions of square-wave exercise at 30% of VT for 10 min (moderate intensity), and at VT + 25%Δ (heavy intensity) for 20 min. Pulmonary gas exchange was measured breath-by-breath. Surface EMG was recorded from m. rectus femoris; integrated EMG (IEMG) and mean power frequency (MPF) were derived for successive contractions. In comparison to moderate-intensity exercise, the phase 2 \(\dot{{V}}\hbox{O}_{2}\) kinetics in heavy exercise were marginally slower than for moderate-intensity exercise (time constant (± SD) 25 ± 9 and 22 ± 10 s, respectively; NS), with a discernible \(\dot{{V}}\hbox{O}_{{2}\,\hbox{sc}}\) (\(\dot{{V}}\hbox{O}_{2}\) difference between minutes 6 and 3 of exercise: 74 ± 21 and 0 ± 20 ml min−1, respectively). However, there was no significant change in IEMG or MPF, either in the moderate domain or in the heavy domain over the period when the slow component was manifest. These observations argue against an appreciable preferential recruitment of fast-twitch units with high force-generating characteristics and fast sarcolemmal conduction velocities in concert with the development of the \(\dot{{V}}\hbox{O}_{2}\) slow component during heavy-intensity knee-extensor exercise. The underlying mechanism(s) remains to be resolved.
Similar content being viewed by others
References
Andersen P, Adams RP, Sjogaard G, Thorboe A, Saltin B (1985) Dynamic knee extension as a model for study of isolated exercising muscle in humans. J Appl Physiol 59:1647–1653
Avogadro P, Dolenec A, Belli A (2003) Changes in mechanical work during severe exhausting running. Eur J Appl Physiol 90:165–170
Barclay CJ, Weber CL (2004) Slow skeletal muscles of the mouse have greater initial efficiency than fast muscles but the same net efficiency. J Physiol (Lond) 559:519–533
Barclay CJ, Constable JK, Gibbs CL (1993) Energetics of fast- and slow-twitch muscles of the mouse. J Physiol (Lond) 472:61–80
Barstow TJ, Molé PA (1991) Linear and nonlinear characteristics of oxygen uptake kinetics during heavy exercise. J Appl Physiol 71:2099–2106
Barstow TJ, Jones AM, Nguyen PH, Casaburi R (1996) Influence of muscle fiber type and pedal frequency on oxygen uptake kinetics of heavy exercise. J Appl Physiol 81:1642–1650
Beaver WL, Wasserman K, Whipp BJ (1973) On-line computer analysis and breath-by-breath graphical display of exercise function tests. J Appl Physiol 34:128–132
Borrani F, Candau R, Millet GY, Perrey S, Fuchslocher J, Rouillon JD (2001) Is the VO2 slow component dependent on progressive recruitment of fast-twitch fibers in trained runners? J Appl Physiol 90:2212–2220
Bull AJ, Housh TJ, Johnson GO, Perry SR (2000) Electromyographic and mechanomyographic responses at critical power. Canad J Appl Physiol 25:262–270
Burnley M, Doust JH, Ball D, Jones AM (2002) Effects of prior heavy exercise on VO2 kinetics during heavy exercise are related to changes in muscle activity. J Appl Physiol 93:167–174
Cautero M, di Prampero PE, Capelli C (2003) New acquisitions in the assessment of breath-by-breath alveolar gas transfer in humans. Eur J Appl Physiol 90:231–241
Crow MT, Kushmerick MJ (1982) Chemical energetics of slow- and fast-twitch muscles of the mouse. J Gen Physiol 79:147–166
Gaesser GA, Poole DC (1996) The slow component of oxygen-uptake kinetics in humans. Exerc Sport Sci Rev 24:35–70
Garland SW, Newham DJ, Turner DL (2004) The amplitude of the slow component of oxygen uptake is related to muscle contractile properties. Eur J Appl Physiol 91:192–198
Grassi B (2005) Limitation of skeletal muscle \(\dot{{V}}\hbox{O}_{2}\) kinetics by inertia of cellular respiration. In: Jones AM, Poole DC (eds) Oxygen uptake kinetics in health and disease. Routledge, UK, pp 212–229
Greenhaff PL, Timmons JA (1998) Pyruvate dehydrogenase complex activation status and acetyl group availability as a site of interchange between anaerobic and oxidative metabolism during intense exercise. Skeletal Muscle Metab Exerc Diab 441:287–298
Han Y-S, Proctor DN, Geiger PC, Sieck GC (2001) Reserve capacity for ATP consumption during isometric contraction in human skeletal muscle fibers. J Appl Physiol 90:657–664
He Z-H, Bottinelli R, Pellegrino MA, Ferenczi MA, Reggiani C (2000) ATP consumption and efficiency of human single muscle fibers with different myosin isoform composition. Biophys J 79:945–961
Jammes Y, Caquelard F, Badier M (1998) Correlation between surface electromyogram, oxygen uptake and blood lactate concentration during dynamic leg exercises. Resp Physiol 112:167–174
Jones AM, Pringle JSM, Carter H (2005) Influence of muscle fibre type and motor unit recruitment on \(\dot{{V}}\hbox{O}_{2}\) kinetics. In: Jones AM, Poole DC (eds) Oxygen uptake kinetics in health and disease. Routledge, UK, pp 261–293
Kellis E (1998) Quantification of quadriceps and hamstring antagonist activity. Sports Med 25:37–62
Krustrup P, Söderlund K, Mohr M, Bangsbo J (2004) The slow component of oxygen uptake during intense, sub-maximal exercise in man is associated with additional fibre recruitment. Pflugers Arch 447:855–866
Kupa EJ, Roy SH, Kandarian SC, DeLuca CJ (1995) Effects of muscle fibre type and size on EMG median frequency and conduction velocity. J Appl Physiol 79:23–32
Kushmerick MJ, Meyer RA, Brown TR (1992) Regulation of oxygen consumption in fast and slow-twitch muscle. Amer J Physiol 263:C598–C606
Lamarra N, Whipp BJ, Ward SA, Wasserman K (1987) Effect of interbreath fluctuations on characterizing exercise gas-exchange kinetics. J Appl Physiol 62:2003–2012
Lucia A, Hoyos J, Chicharro JL (2000) The slow component of VO2 in professional cyclists. Br J Sports Med 34:367–374
Meyer RA, Brown TR, Kushmerick MJ (1985) Phosphorus nuclear magnetic resonance of fast- and slow-twitch muscle. Am J Physiol 248:C279-C287
Özyener F, Rossiter HB, Ward SA, Whipp BJ (2001) Influence of exercise intensity on the on- and off-transient kinetics of pulmonary oxygen uptake in humans. J Physiol 533:891–902
Pozzo M, Merlo E, Farina D, Antonutto G, Merletti R, di Prampero PE (2004) Muscle-fiber conduction velocity estimated from surface EMG signals during explosive dynamic contractions. Muscle Nerve 29:823–833
Pringle JSM, Jones AM (2002) Maximal lactate steady state, critical power and EMG during cycling. Eur J Appl Physiol 88:214–226
Pringle JSM, Doust JH, Carter H, Tolfrey K, Campbell IT, Jones AM (2003a) Oxygen uptake kinetics during moderate, heavy and severe intensity ‘submaximal‘ exercise in humans: the influence of muscle fibre type and capillarisation. Eur J Appl Physiol 89:289–300
Pringle JSM, Doust JH, Carter H, Tolfrey K, Jones AM (2003b) Effect of pedal rate on primary and slow-component oxygen uptake responses during heavy-cycle exercise. J Appl Physiol 94:1501–1507
Rossiter HB, Ward SA, Kowalchuk JM, Howe FA, Griffiths JR, Whipp BJ (2002a) Dynamic asymmetry of phosphocreatine concentration and O2 uptake between the on- and off-transients of moderate- and high-intensity exercise in humans. J Physiol (Lond) 541:991–1002
Rossiter HB, Ward SA, Howe FA, Kowalchuk JM, Griffiths JR, Whipp BJ (2002b) Dynamics of intramuscular P-31-MRS Pi peak splitting and the slow components of PCr and O2 uptake during exercise. J Appl Physiol 93:2059–2069
Rossiter HB, Howe FA, Ward SA (2005) Intramuscular [PCr] and pulmonary \(\dot{{V}}\hbox{O}_{2}\) kinetics: implications for control of muscle oxygen consumption. In: Jones AM, Poole DC (eds) Oxygen uptake kinetics in health and disease. Routledge, UK, pp 154–184
Russell A, Wadley G, Snow R, Giacobino JP, Muzzin P, Garnham A, Cameron-Smith D (2002) Slow component of VO2 kinetics: the effect of training status, fibre type, UCP3 mRNA and citrate synthase activity. Int J Obes Relat Metab Disord 26:157–64
Sabapathy S, Schneider DA, Comadira G, Johnston I, Morris NR (2004) Oxygen uptake kinetics during severe exercise: a comparison between young and older men. Respir Physiol Neurobiol 139:203–213
Saunders MJ, Evans EM, Arngrimsson SA, Allison JD, Warren GL, Cureton KJ (2000) Muscle activation and the slow component rise in oxygen uptake during cycling. Med Sci Sports Exerc 32:2040–2045
Scheuermann BW, Hoelting BD, Noble L, Barstow TJ (2001) The slow component of O2-uptake is not accompanied by changes in muscle EMG during repeated bouts of heavy exercise in humans. J Physiol 531:245–256
Scheuermann BW, McConnell JHT, Barstow TJ (2002) EMG and oxygen uptake responses during slow and fast ramp exercise in humans. Exp Physiol 87:91–100
Shinohara M, Moritani T (1992) Increase in neuromuscular activity and O2 uptake during heavy exercise. Ann Physiol Anthrop 11:257–262
Vøllestad NK, Blom PC (1985) Effect of varying exercise intensity on glycogen depletion in human muscle fibres. Acta Physiol Scand 125:395–405
Vøllestad NK, Hermansen L (1984) Muscle glycogen depletion in human-muscle fiber types during submaximal exercise. Acta Physiol Scand 121:A38
Vøllestad NK, Vaage O, Hermansen L (1984) Muscle glycogen depletion patterns in type I and subgroups of type II fibres during prolonged severe exercise in man. Acta Physiol Scand 122:433–441
Wasserman K, Stringer WW, Casaburi, R (1995) Is the slow component of \(\dot{{V}}\hbox{O}_{2}\) a respiratory adaptation to anaerobiosis? Adv Exp Med Biol 393:187–194
Whipp BJ (1987) Dynamics of pulmonary gas exchange. Circulation 76(Suppl. Vl):18–28
Whipp BJ (1994) The slow component of oxygen uptake kinetics during heavy exercise. Med Sci Sports Exerc 26:1319–1326
Whipp BJ, Rossiter HB (2005) The kinetics of oxygen uptake: physiological inferences from the parameters. In: Jones AM, Poole DC (eds) Oxygen uptake kinetics in sport, exercise and medicine. Routledge, London, pp 64–94
Whipp BJ, Ward SA, Lamarra N, Davis JA, Wasserman K (1982) Parameters of ventilatory and gas exchange dynamics during exercise. J Appl Physiol 52:1506–1513
Whipp BJ, Ward SA, Wasserman K (1986) Respiratory markers of the anaerobic threshold. Adv Cardiol 35:47–64
Whipp BJ, Rossiter HB, Ward SA (2002) Exertional oxygen uptake kinetics: a stamen of stamina? Biochem Soc Trans 30:237–247
Yoshida T, Watari H (1994) Exercise-induced splitting of the inorganic phosphate peak: investigation by time-resolved 31P-nuclear magnetic resonance spectroscopy. Eur J Appl Physiol 69:465–473
Acknowledgements
This work was supported in part by The Physiological Society. The authors would like to thank Bill Anderson (London South Bank University) and Richard Twycross-Lewis (Queen Mary, University of London) for their technical contributions. These experiments comply with the current laws of the country in which they were performed.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Garland, S.W., Wang, W. & Ward, S.A. Indices of electromyographic activity and the “slow” component of oxygen uptake kinetics during high-intensity knee-extension exercise in humans. Eur J Appl Physiol 97, 413–423 (2006). https://doi.org/10.1007/s00421-006-0185-x
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00421-006-0185-x