Maximal lactate steady state determination with a single incremental test exercise.
The aim of this study was to determine whether the power output associated with a maximal lactate steady state (MLSS) (.W(MLSS)) can be assessed using a single incremental cycling test. Eleven recreational sportsmen (age: 22+/-1 years, height: 175+/-6 cm, weight: 71+/-5 kg) volunteered to participate in the study. For each subject the first and second ventilatory thresholds (VT(1) and VT(2), respectively) and the power output corresponding to (respiratory exchange ratio) RER=1.00 were determined during an incremental test to exhaustion. Thereafter, each subject performed several 30-min constant load tests to determine MLSS. The workload used in the first constant test was set to the .W(RER=1.00) determined during the incremental test. .W(VT1) (175+/-24 W) and .W(VT2) (265+/-31 W) were significantly different from .W(MLSS )(220+/-36 W). Whereas, .W(RER=1.00) (224+/-33 W) was similar to .W(MLSS). HR, RER and .VE were significantly different between the 10th and the 30th minutes when exercising at .W(RER=1.00) and at .W(MLSS). In contrast, .VO(2) and .VCO(2) were stable over those 30-min constant tests. Power output at VT(1), RER=1.00 and VT(2) were all correlated to .W(MLSS) but the relationship was stronger between RER=1.00 and MLSS (R (2)=0.95). The present study shows that the power output associated with a RER value equal to 1.00 during an incremental test does not differ from that determined for MLSS. Hence, the MLSS can be estimated with a single exercise test.
Laplaud
David
D
UF de Biologie et Médecine du Sport, Service EFCR Pr Lévy, CHU Grenoble, BP 185, 38042 Grenoble Cedex 09, France.
Guinot
Michel
M
Favre-Juvin
Anne
A
Flore
Patrice
P
D000328:Adult; D004735:Energy Transfer / Q000502:physiology*; D015444:Exercise; D005080:Exercise Test / Q000379:methods; D006801:Humans; D019344:Lactic Acid / Q000097:blood*; D008297:Male; D010101:Oxygen Consumption
D019344:Lactic Acid