Fatigue and recovery from dynamic contractions in men and women differ for arm and leg muscles.

INTRODUCTION Whether there is a gender difference in fatigue and recovery from maximal velocity fatiguing contractions and across muscles is not understood. METHODS Sixteen men and 19 women performed 90 isotonic contractions at maximal voluntary shortening velocity (maximal velocity concentric contractions, MVCC) with the elbow flexor and knee extensor muscles (separate days) at a load equivalent to 20% maximal voluntary isometric contraction (MVIC). RESULTS Power (from MVCCs) decreased similarly for men and women for both muscles (P > 0.05). Men and women had similar declines in MVIC of elbow flexors, but men had greater reductions in knee extensor MVIC force and MVIC electromyogram activity than women (P < 0.05). The decline in MVIC and power was greater, and force recovery was slower for the elbow flexors compared with knee extensors. CONCLUSIONS The gender difference in muscle fatigue often observed during isometric tasks was diminished during fast dynamic contractions for upper and lower limb muscles.