The leveling-off of oxygen uptake is related to blood lactate accumulation. Retrospective study of 94 elite rowers.
To assess whether the ability to demonstrate a plateau in oxygen consumption VO2 could be related to adaptation to exercise, the data obtained over a period of 10 years on 94 elite oarsmen who had participated in annual testing were re-evaluated. The test consisted in an incremental step protocol until volitional exhaustion. VO2, heart rate (HR), blood lactate ([La]b) and respiratory exchange ratio (RER) were measured at each step. The maximal oxygen consumption (VO2max), the power corresponding to VO2maxPamax and the maximal power achieved (Ppeak) were recorded. Thirty-eight oarsmen achieved a VO2 plateau and were designated as Pla; 56 did not and were designed as N-Pla. The Pla and N-Pla VO2max, Pamax and maximal HR values were similar. In comparison with N-Pla, the Pla group displayed a rightward shift of the [La]b versus power curve, accounted for by both the increased percentage of VO2max corresponding to 4 mmol l(-1) and the decreased value of [La]b corresponding to Pamax (P<0.05). Pla oarsmen attained a higher Ppeak expressed as % of Pamax (P<0.05) and also showed better ergometer performance (P<0.05). In a sub-group of 53 oarsmen constituted on the basis of Pamax values close to 400 W, for a given power output, the Pla subjects had significantly lower HR, RER, and [La]b values at each sub-maximal stage of the test. These results suggest that achieving a [Formula: see text] plateau during completion of an incremental step protocol accounts for greater muscle ability to maintain homeostasis during exercise. These differences give the oarsmen an advantage in rowing competitions.
Lacour
Jean-René
JR
Laboratoire de Biomécanique et Mécanique des Chocs, Université C. Bernard Lyon 1, Faculté Médecine Lyon-Sud, BP12, 69921, Oullins Cedex, France.
Messonnier
Laurent
L
Bourdin
Muriel
M
D000222:Adaptation, Physiological / Q000502:physiology; D000328:Adult; D015308:Anaerobic Threshold / Q000502:physiology; D015444:Exercise / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007773:Lactates / Q000378:metabolism*; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology; D012189:Retrospective Studies; D013177:Sports
D007773:Lactates