A077: Effect of Ischemic Preconditioning on Upper Limb After a Heavy LoadSwimming Training

<bold>Purpose:</bold> Ischemic preconditioning (IPC) is a short, noninvasive and intermittent ischemic treatment of limbs before exercise. The aim of this study was to compare the effects of acute or repeated IPC on upper arm skeletal muscle strength and circumference after a heavy load swimming training. <bold>Methods:</bold> College students majoring in swimming were randomly divided into CON group, acute IPC group (the intervention lasted 7 days, AIPC) and repeated IPC group (intervention for 1 day, RIPC), and IPC intervention was performed before a high-load swimming training. The three groups were all 4×5min with CON pressure of 20mmHg and IPC pressure of 220mmHg. Upper limb tension, grip strength, upper arm circumference, and shoulder circumference were measured at baseline and 0h, 24h, and 48h after exercise. <bold>Results:</bold> 1) the IPC after exercise intervention group in upper limb tension, grip strength and upper arm circumference were significantly greater than the change range of CON. This indicates that the IPC intervention promoted the four indices after training to maintain and restore. 2) After 24h of exercise, the reduction of upper limb tension in RIPC group was significantly lower than that in AIPC group, and the reduction of upper arm circumference was significantly faster than that in AIPC group. Indicating that the recovery effect of RIPC on upper limb tension and upper arm circumference was better than that of AIPC group. 3) Concurrently, there were no significant differences in shoulder circumference between groups, and whether IPC intervention was performed did not seem to affect the recovery of shoulder circumference after training. <bold>Conclusion:</bold> IPC can effectively promote the upper arm skeletal muscle strength and circumference after heavy load swimming training. RIPC intervention to the recovery of tension and circumference of upper arm more effective than that of AIPC.