Blood Lactate Increase During the Force Velocity Exercise Test

Abstract

Venous blood lactate concentration was measured during the force velocity exercise test in order to determine whether this test is strictly alactic or whether it draws upon lactic anaerobic metabolism. Nine trained male subjects, aged from 23 to 29 years, participated in this study. Two blood samples were drawn at rest, and then for each work load (1 kg to 10 kg): at the end of each sprint (S1) and at the 5^thminute of recovery (S₂). From the first braking force, venous blood lactate concentration increased very significantly during the force velocity test (p < 0.001) and, once the peak of power has been obtained, the venous blood lactate concentration remained steady. The lactate increase for each load (Δ[LA]) decreased significantly (p < 0.01). From the beginning of the exercise to the peak of power, a significant positive correlation between the increase of power and the increase of blood lactate concentration measured at S₂ existed (r = 0.71, p < 0.001), whereas there was a negative correlation between the decrease of Δ[LA] and the increase of power (r= -0.45, p < 0.01). In conclusion, the repetition of sprints during the force velocity test induced a recruitment of lactic anaerobic metabolism. Maximal power must be considered as an alactic and lactic anaerobic power. The consequences of lactate accumulation in muscle may be a limitation of the maximal anaerobic power.

Key words

Exercise - force velocity test - anaerobic - lactate