Remote Ischemic Preconditioning Increases Maximal Accumulated Oxygen Deficit in Cross-Country Endurance Runners.

PURPOSE: To test the hypothesis that remote ischemic preconditioning (IPC) improves severe intensity exercise performance in competitive cross-country endurance runners by increasing maximal accumulated oxygen deficit (AOD), an indicator of anaerobic capacity.

METHODS

A randomized sham-controlled crossover study was employed in which 14 competitive trained male cross-country athletes (peak oxygen uptake [V˙O2peak]: 62 [5] mL·kg-1·min-1) completed 3 maximal running trials (baseline, sham, remote IPC) at ∼110% V˙O2peak to their limit of tolerance. Remote IPC was induced with 4 × 5-minute cycles of brachial artery occlusion with 5 minutes of reperfusion. Maximal AOD (in milliliters per kilogram) and oxygen uptake (V˙O2) kinetics for each trial were derived from gas-exchange measures.

RESULTS

Remote IPC (146 [58] s, 95% CI, 112-181) significantly increased the running limit of tolerance by 12% compared with baseline (131 [47] s, 95% CI, 102-160, P = .01), and 17% versus sham (125 [44] s, 95% CI, 96-154, P = .002). Likewise, with remote IPC, maximal AOD was 58.4 (12.2) mL/kg (95% CI, 51.3-65.5), a substantial increase compared with baseline (45.5 [9.1] mL/kg, P < .001, 95% CI, 40.3-50.8) and sham (46.4 [7.1] mL/kg, P = .01, 95% CI, 42.3-50.5). Analysis of V˙O2 kinetics revealed that remote IPC did not change the phase II time constant, but increased mean response time (17.6 [5.1] s) compared with baseline (15.5 [3.8] s, P = .014) and sham (15.8 [3.2] s, P = .04).

CONCLUSION

Remote IPC improved running performance in men cross-country athletes. Greater anaerobic capacity, as estimated by increased maximal AOD, may contribute to these performance improvements. Coaches and athletes may consider incorporating IPC into precompetition warm-ups to enhanced running tolerance and anaerobic capacity in trained runners.