The effect of acute and repeated ischemic preconditioning on recovery following exercise-induced muscle damage.

The aim of this investigation was to determine if acute or repeated applications of ischemic preconditioning (IPC) could enhance the recovery process, following exercise induced muscle damage (EIMD). Randomized control trial. Twenty-three healthy males were familiarised with the muscle damaging protocol (five sets of 20 drop jumps from a 0.6 m box) and randomly allocated to one of three groups: SHAM (3 × 5 min at 20 mmHg), Acute IPC (3 × 5 min at 220 mmHg) and Repeated IPC (3 days x 3 × 5 min at 220 mmHg). The indices of muscle damage measured included creatine kinase concentration ([CK]), thigh swelling, delayed onset muscle soreness, counter movement jumps (CMJ) and maximal voluntary isometric contraction (MVIC). Both acute and repeated IPC improved recovery in MVIC versus SHAM. Repeated IPC led to a faster MVIC recovery at 48 h (101.5%) relative to acute IPC (92.6%) and SHAM (84.4%) (P <  0.05). Less swelling was found for both acute and repeated IPC vs. SHAM (P <  0.05) but no group effects were found for CMJ, soreness or [CK] responses (P >  0.05). Taken together, repeated IPC can enhance recovery time of MVIC more than an acute application, and both reduce swelling following EIMD, relative to a SHAM condition. [Abstract copyright: Copyright © 2021 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.]