Effect Of Ischemic Preconditioning On Swimming Performance: A Case Study On Two Elite Male Swimmers

To date the published literature investigating the ergogenic effect of ischemic preconditioning (IPC) on swimming performance remains ambiguous, with some observing improvements in 50-m and 100-m time trial performance while others reporting no influence on 100-m or 200-m times following IPC. As with many ergogenic aids, efficacy appears to vary across training phenotypes. However, there is very little data investigating the effects of IPC on truly elite, making it difficult to draw conclusions on the ‘real-world’ applicability of IPC in sport. PURPOSE: Given the inherent challenges of accessibility and/or limited opportunities to manipulate training or testing elite athletes, we designed this case study in consultation with coaches to specifically address whether or not IPC acutely improves swim times across a variety of distances, particularly those associated with rates consistent with maintainable swim speeds. METHODS: Two elite male swimmers completed a series of time trials preceded by an intervention of either ischemic preconditioning (IPC) (4 x 5-min bilateral leg and arm occlusions at 220 mmHg) or sham (simulation of therapeutic ultrasound) on two separate occasions. The exercise protocol consisted of a standardized warmup followed by four consecutive freestyle time trials (50, 100, 200, 1000-yd), with a 6-min active recovery between efforts. For each time trial, total time and 50-yd splits were recorded, along with stroke length (SL) and stroke rate (SR). RESULTS: We observed ~2.4% improvement for both swimmers in the 1000-yd time trial (swimmer 1: 668.8 (IPC) vs. 684.5 (sham); swimmer 2: 564.8 s (IPC) vs. 579.3 s (sham)) following IPC. Fastest, slowest and average 50-yd split time were also improved during the 1000-yd trial for swimmer 1 by 0.32 s (1.1%), 1.09 s (3%), 0.78 s (2.3%), and for swimmer 2 by 0.27 s (1%), 0.64 s (2.2%), 0.73 s (2.5%), respectively. Commensurate with times, there was a 0.04 yd·s-1 improvement in swim velocity during 1000-yd (2.7%) time trial for swimmer 1, and a 0.04 yd·s-1 for swimmer 2 during the 1000-yd (2.3%) time trial following IPC. CONCLUSIONS: Improvements in swim velocity were most likely due to improved SR observed in both swimmers (~ 1 stroke·min-1 increase during IPC), as SL did not change.