The effect of caffeine ingestion on torque and muscle activity during resistance exercise men
Michael J. Duncan Muscle & Nerve Accepted Article (Accepted, unedited articles published online and citable)
We examined the effect of caffeine ingestion on muscle torque production and muscle activity at different contraction speeds in trained men. Methods: 10 men (mean age ± SD = 22 ± 1.1 years) volunteered to participate. A double-blind, randomized cross-over design was used.
Sixty minutes post ingestion of caffeine (6mg kg-1) or placebo, participants completed 6 repetitions of isokientic knee extension at 3 angular velocities (30°s-1, 150°s-1, 300°s-1) from which peak torque was determined. Electromyographic activity of the vastus medialis was also collected.
Results: Repeated measures ANOVA indicated that muscle torque production was significantly higher (P = 0.02) with caffeine compared to placebo. A significant (P = 0.02) substance by velocity interaction for muscle activity indicated significantly higher vastus medialis muscle activity in the presence of caffeine vs. placebo, and this difference was amplified as angular velocity increased.
Conclusions Acute caffeine ingestion improves muscle performance and increases muscle activity during short-duration maximal dynamic contractions.