The effect of lower limb massage on EMG and force production of the knee extensors Running Head: Neuromuscular recruitment and force production of massaged skeletal muscle

Objectives: This study evaluated the effect of massage on force production and neuromuscular recruitment. Methods: Ten healthy male subjects performed isokinetic concentric contractions on the knee extensors at speeds of 60, 120, 180 and 240o.s. These contractions were performed before and after a 30 minute intervention of either rest in the supine position or lower limb massage. Electromyography (EMG) and force data was captured during the contractions. Results: The change in isokinetic mean force from pre to post intervention showed a significant decrease (p<0.05) at 60 o.s and a trend for a decrease (p=0.08) at 120o.s as a result of massage in comparison to passive rest. However, there were no corresponding differences in any of the EMG data. A reduction in force production was shown at 60 o.s with no corresponding alteration in neuromuscular activity. Conclusion: This suggests that motor unit recruitment and muscle fibre conduction velocity are not responsible for the observed reductions in force. Although experimental confirmation is necessary, one possible suggestion is that massage may have induced force loss by influence on “muscle architecture”. However, it is possible that the differences were only found at 60 o.s as it was the first contraction post massage. Further work is therefore needed on examining both muscle tension and architecture post massage and the duration of any massage effect.