ACUTE LOW-DOSE CAFFEINE SUPPLEMENTATION INCREASES ELECTROMYOGRAPHIC FATIGUE THRESHOLD IN HEALTHY MEN

The purpose of this study is to determine whether consumption of a single low-dose caffeine drink will delay the onset of the electromyographic fatigue threshold (EMG(FT)) in the superficial quadriceps femoris muscles. We hypothesize that the EMG(FT) values for the caffeine condition will be significantly higher than the EMG(FT) values for the placebo condition. On separate occasions, 10 physically active men performed incremental single-leg knee-extensor ergometry 1 hour after caffeine (200 mg) or placebo consumption. The EMG(FT) was determined for each participant for both conditions. The results indicated a significant increase for maximal power output (16%; p = 0.004) and EMG(FT) (45%; p = 0.004) in the caffeine condition compared with placebo. These findings suggest that acute low-dose caffeine supplementation delays neuromuscular fatigue in the quadriceps femoris muscles.