The Specificity of Muscular Coordination between Front Crawl Swimming and Dry-land Resistance Training Exercises.

PURPOSE: Specificity is an integral component in understanding the mechanism of transfer of dry-land resistance training exercises (RT) to front crawl swimming (FC). The specificity of intra and inter muscular coordination is deemed to be important, with neuromuscular adaptations at the forefront namely motor unit recruitment, synchronisation and co-contraction. Limited research has investigated the muscular coordination between FC and RT. Therefore, the aim of this investigation is to explore the muscular coordination between RT and FC. METHODS: Fourteen male international and national level swimmers were recruited. EMG and 2D kinematic data were collected whilst FC, bench press (BP) and pull-up (PU) were performed. A standardised warm up was conducted followed by 3 x 35 m FC bouts, 1 x 70 % and 2 x 100 % of maximal exertion, with 5 minutes’ recovery between bouts. The BP and PU were performed using the same protocol, with participants performing 3 x 5 RM. EMG data were filtered using a 4th order Butterworth filter and normalised to peak EMG. The EMG data were presented using a 50 % threshold of peak EMG and demonstrated temporal overlaps (TO) for each muscle. 2D data were collected during the propulsive (PRO) phase of FC and eccentric (ECC) and concentric (CONC) phase of BP and PU. RESULTS: The individual results show little TO between FC and BP and FC and PU. Furthermore, FC and BP had significantly (P < 0.05) greater TO compared to FC and PU. The ratio of the ECC and CONC phase during the 5RM, BP and PU, show significant (P < 0.001) differences compared to the recovery (REC) and PRO phase of FC. Additionally, duration of time under tension during the CONC phase, of BP (P < 0.01) and PU (P < 0.001), was significantly higher than during the PRO phase of FC. CONCLUSION: The EMG data shows different individual responses and little specificity between FC and BP and FC and PU. The targeted prime movers show little TO between FC and RT. These findings may question the validity of this method for assessing specificity, as it does not account for their dynamic nature. The lack of specificity between RT and FC shows further differences as the ratio and duration of time under tension of the RT compared to FC show significant differences. Velocity based training may be a viable method to target specific movement velocities and increase specificity.