The purpose of the present study was to determine
whether there are any differences in power output (PO) and/or
quadriceps muscle (Quad) activity between black African and
Caucasian football players during a force-velocity (fv) exercise
test, which consisted of performing maximal 6-s sprints against
an increasing load. Each subject started the test with a load of 2
kg and then recovered for 5 min before repeating the same test
with a load increased by 2 kg. When the pedal frequency did not
exceed 130 rev·min–1, the load was increased by only 1 kg.
Each subject attained the load corresponding to his maximal
power if an additional increase in load (+1 kg) induced a power
decrease. Nine black Africans (mean age 24.2 ± 3.3 years) and
nine Caucasians (24.7 ± 4.2 years) (matched for stature and
aerobic fitness) participated in the fv exercise test. During the
test, PO, blood lactate, and the quadriceps electromyography
(EMG) root mean square (Quad RMS) were assessed. Higher
blood lactate was observed in Caucasians than in black Africans
for POs over the load range from 4 kg up to the maximal power.
However, PO and Quad RMS values were similar in Caucasians
and black Africans. They also had similar lean leg volume (LLV)
and consequently produced similar PO/LLV and Quad RMS/LLV
values. Overall, our results suggest that Caucasians and black
Africans matched for stature, max, and training background
have similar PO and Quad RMS values, but different blood lactate
concentrations during brief, intermittent, intense exercise
performed on a cycloergometer.