To examine muscular fatigue of the shoulder’s internal rotators alongside swimming biomechanics during long-duration sub-maximal swimming sets performed within two different speed domains. Methods: Eight trained swimmers (mean ± SD 20.5 ± 0.9 years, 173 ± 10 cm, 71.3 ± 10.0 kg) raced over three distances (200, 400, 800-m races) for determination of Critical Speed (CS; slope of thed-trelationship). Following a familiarisation to muscular isokinetic testing, they subsequently randomly performed two constant-speed efforts (6 x 5-min blocks; 2.5-min recovery) 5% above (T105)and 5% below CS (T95)with Maximal Voluntary Contractions recorded in-between swimming blocks. Results: Capillary blood lactate concentration ([La]), RPE, peak torque, stroke length and stroke rate were maintained throughout T95(P<0.05). [La], RPE and stroke rate increased alongside concomitant decreases in maximal torque and stroke length during T105(P<0.05) with incapacity for the swimmers to maintain the pace for longer than ~20 minutes. For T105, changes in maximal torque (35.0 ± 14.9 to 25.8 ± 12.1 N.m) and in stroke length (2.66 ± 0.36 to 2.23 ± 0.24 m.cycle-1) were significantly correlated (r=0.47, P<0.05). Conclusion: While both muscular fatigue (shoulder’s internal rotators) and task failure occur when swimming at a pace greater than CS, the 2.5-min recovery period during the sub-CS set possibly alleviated the development of muscular fatigue, for the pace to be sustainable for 6 x 5 min at 95% of CS. A causal relationship between reduction in stroke length and loss of muscular strength should be considered very cautiously in swimming.
|Number of pages||6|
|Journal||International Journal of Sports Physiology and Performance|
|Publication status||Published - 1 Oct 2015|
Bibliographical note© 2015 Human Kinetics, Inc., as accepted for publication
- distance-time relationship
- critical power