Abstract
Objectives: The present study aimed to determine the effects of ischemic preconditioning on performance in three successive 50-m swimming trials and to measure stroke rate, stroke length and blood lactate accumulation.
Design: Counterbalanced, repeated-measures cross-over study.
Methods: On two separate days, eleven competitive male swimmers (20 ± 3 years, 182 ± 5 cm, 77 ± 5 kg) performed three successive 50-m trials in a 50-m swimming pool, preceded by intermittent bilateral cuff inflation (4× 5-min of blood flow restriction + 5-min of cuff deflation) at either 220 for thighs and 180 mmHg for arms (ischemic preconditioning) or 20 mmHg for both limbs (control-treatment). The 50-m trials were conducted 1-, 2-, and 8-h after the procedure.
Results: While no ergogenic effect of ischemic preconditioning was observed for 1-h (0.4%, 95% confidence limits of ±0.6%, p = 0.215), there were clear beneficial effects of ischemic preconditioning on 2- and 8-h (1.0% and 1.2%, respectively; 95% confidence limits of ±0.6% in both cases, p ≤ 0.002). Furthermore, ischemic preconditioning increased blood lactate accumulation in 2-(p < 0.001) and 8-h (p = 0.010) and stroke rate for 2- and 8-h in specific 10-m segments (p < 0.05).
Conclusions: These findings suggest a time-dependent effect of ischemic preconditioning on 50-m swimming performance for competitive athletes, with the time window of the beneficial effect starting after about 2-h and lasting for at least 8-h after ischemic preconditioning. This change in performance was accompanied by an increase in blood lactate accumulation and faster strokes in front crawl.
Practical Implication by Erin Cameron DPT: This study demonstrates that ischemic preconditioning (IPC) can be used to enhance sprinting performance. As no significant improvement was seen 1 hour post intervention, coaches and swimmers who are considering IPC should schedule a longer time period (between 2-8 hours) between IPC and sprint events.
Though IPC has demonstrated performance enhancement in college aged sprinters, it’s mechanism of improving performance is not well understood, nor has it been shown to be appropriate for swimmers of all ages.
Reference:
- Felipe D. Lisbôaa, Tiago Turnes, Rogério S.O. Cruz, João A.G. Raimundoa,
Gustavo S. Pereira, Fabrizio Caputoa. The time dependence of the effect of ischemic preconditioning on successive sprint swimming performance. Journal of Science and Medicine in Sport. 20 (2017) 507–511.