The purpose of this study was to compare the effect of two different types of cyclic severe exercise (running and cycling) on the V˙O2 slow component. Moreover we examined the influence of cadence of exercise (freely chosen [FF] vs. low frequency [LF]) on the hypothesis that: 1) a stride frequency lower than optimal and 2) a pedalling frequency lower than FF one could induce a larger and/or lower V˙O2 slow component. Eight triathletes ran and cycled to exhaustion at a work-rate corresponding to the lactate threshold + 50 % of the difference between the work-rate associated with V˙O2max and the lactate threshold (Δ 50) at a freely chosen (FF) and low frequency (LF:- 10 % of FF). The time to exhaustion was not significantly different for both types of exercises and both cadences (13 min 39 s, 15 min 43 s, 13 min 32 s, 15 min 05 s for running at FF and LF and cycling at FF and LF, respectively). The amplitude of the V˙O2 slow component (i.e. difference between V˙O2 at the last and the 3rd min of the exercise) was significantly smaller during running compared with cycling, but there was no effect of cadence. Consequently, there was no relationship between the magnitude of the V˙O2 slow component and the time to fatigue for a severe exercise (r = 0.20, p = 0.27). However, time to fatigue was inversely correlated with the blood lactate concentration for both modes of exercise and both cadences (r = - 0.42, p = 0.01). In summary, these data demonstrate that: 1) in subjects well trained for both cycling and running, the amplitude of the V˙O2 slow component at fatigue was larger in cycling and that it was not significantly influenced by cadence; 2) the V˙O2 slow component was not correlated with the time to fatigue. If the nature of the linkage between the V˙O2 slow component and the fatigue process remains unclear, the type of contraction regimen depending on exercise biomechanic characteristics seems to be determinant in the V˙O2 slow component phenomenon for a same level of training.
1
Ahlquist L E, Bassett D R, Sufit R, Nagle F J, Thomas D P.
The effect of pedalling frequency on glycogen depletion rates in type I and II quadriceps muscle fibers during submaximal cycling exercise.
Eur J Appl Physiol.
1992;
65
360-4
6
Barstow T J, Jones A M, Nguyen P H, Casaburi R.
Influence of muscle fiber type and pedal frequency on oxygen uptake kinetics of heavy exercise.
J Appl Physiol.
1996;
81
1642-50
7
Billat V L, Binsse V, Haouzi P, Koralsztein J P.
High level runners are able to maintain a V˙O2 steady-state below V˙O2max in an all-out run over their critical velocity.
Arch Physiol Bioch.
1998;
107
1-8
8
Billat V L, Richard R, Binsse V M, Koralsztein J P, Haouzi P.
V˙O2 slow component for a severe exercise depends on type of exercise and is not correlated with time to fatigue.
J Appl Physiol.
1998;
85
2118-2124
9
Capelli C, Antonutto G, Zamparo P, Girardis M, di Prampero P E.
Effects of prolonged cycle ergometer exercise on maximal muscle power and oxygen uptake in humans.
Eur J Appl Physiol.
1993;
66
189-95
13
Cavagna G A, Willems P A, Franzetti P, Detrembleur C.
The two power limits conditioning step frequency in human running.
J Physiol.
1991;
437
95-108
16
Coyle E F, Labros S, Sidossis S, Horowitz J F, Beltz J D.
Cycling efficiency is related to the percentage of type I muscle fibers.
Med Sci Sports Exerc.
1993;
25
1269-74
17
Farrel P E, Wilmore J H, Coyle E F, Billing J E, Costill D L.
Plasma lactate accumulation and distance running performance.
Med Sci Sports Exerc.
1979;
11
338-44
23 Jones L A. The senses of effort and force during fatiguing contractions. In: Gandevia SC et al. (eds). Fatigue. Neural and Muscular Mechanisms. New York:; Plenum Press, 1995: 305-13
24 Mahler M. Kinetics and control of oxygen consumption in skeletal muscle. In: Cerretelli P, Whipp BJ (eds). Exercise Bioenergetics and Gas Exchange. Elsevier/North-Holland:; Biomedical Press publishers, 1980: 53-66
26
Morgan D, Martin P, Craib M, Caruso C, Clifton R, Hopewell R.
Effect of step length optimization on the aerobic demand of running.
J Appl Physiol.
1994;
77
245-51
27
Moritani T, Nagata A, De Vries H A, Muro M.
Critical power as a measure of physical working capacity and anaerobic threshold.
Ergonomics.
1981;
24
339-50
28
Nagle F J, Robinhold D, Howley E, Daniels J, Baptista G, Stoedefalke K.
Lactic acid accumulation during running at submaximal aerobic demands.
Med Sci Sports Exerc.
1970;
2
182-6
29
Newsholme E A, Blomstrand E, Ekblom B.
Physical and mental fatigue: metabolic mechanisms and importance of plasma amino acids.
Br Med Bull.
1992;
48
477-95
30
Okita K, Nishijima H, Yonezawa K, Ohtsubo M, Hanada A, Kohya T, Murakami T, Kitabatake A.
Skeletal muscle metabolism in maximal bicycle and treadmill exercise distinguished by using in vivo metabolic freeze method and phosphorus-31 magnetic resonance spectroscopy in normal men.
Am J Cardiol.
1998;
81
106-9
32
Poole D C, Ward S A, Gardner G W, Whipp B J.
Metabolic and respiratory profile of the upper limit for prolonged exercise in man.
Ergonomics.
1988;
31
1265-79
33
Poole D C, Schaffartzik W, Knight D R, Derion T, Kennedy B, Guy H J, Prediletto R, Wagner P D.
Contribution of exercising legs to the slow component of oxygen uptake kinetics in humans.
J Appl Physiol.
1991;
71
1245-53
34
Poole D C, Barstow T J, Gaesser G A, Willis W T, Whipp B J.
V˙O2 slow component: physiological and functional significance.
Med Sci Sports Exerc.
1994;
26
1354-8
35
Roston W L, Whipp B J, Davis J A, Cunningham D A, Effros R M, Wasserman K.
Oxygen uptake kinetics and lactate concentration during exercise in humans.
Am Rev Respir Dis.
1987;
135
1080-4
37
Stringer W S, Wasserman K, Casaburi R, Porszasz J, Maehara K, French W.
Lactic acidosis as facilitator of oxyhemoglobin dissociation during exercise.
J Appl Physiol.
1994;
76
1462-7
38
Takaishi T, Yasuda Y, Ono T, Moritani T.
Optimal pedalling rate estimated from neuromuscular fatigue for cyclists.
Med Sci Sports Exerc.
1996;
28
1492-7
39
Takaishi T, Yamamoto T, Ono T, Ito T, Moritani T.
Neuromuscular, metabolic, and kinetic adaptations for skilled pedalling performance in cyclists.
Med Sci Sports Exerc.
1998;
30
442-9