Effects of Severe Prior Exercise on Assessment of Maximal Oxygen Uptake during One- versus Two-Legged Cycling

Abstract

Physiological responses to consecutive (separated by 7 minutes) continuous type I and two-legged (2L) maximal oxygen uptake ([Vdot]O₂ max) tests have been studied on 11 male subjects. One-legged cycling tests were conducted as either two consecutive right-legged (R) tests or a left-legged (L) test preceeding an R. It was hypothesized that series R-R would result in greater inhibition of second test performance than series L-R, owing to more rapid attainment of peak muscle lactate accumulation. It was further hypothesized that second test performance with two legs would be more severely restricted than with one leg, owing to reduced cardiac output ([Qdot]) attributable to pooling of blood in immobilized areas. No reductions in [Vdot]O₂ max were found from test 1 (T₁) to test 2 (T₂) in either one-legged series. Performance time was significantly (p < .05) reduced in T₂ of each one-legged series; however, no differences were found between T₂ tests. Limiting factors associated with T₂ performance in series L-R and R-R exerted similar influence and therefore the hypothesized effect of peak lactate accumulation was not demonstrated. [Vdot]O₂ max and performance time were significantly (p < .05) reduced from T₁ to T₂ in two-legged cycling and Δ performance time scores (T₁ minus T₂) among treatments were significantly (p < .05) greater during series 2L. It was indicated that the significantly reduced [Qdot] observed in each series served to more greatly affect series 2L as hypothesized.