Abstract:
Blood flow restriction (BFR) training has been advocated as an alternative approach for improving muscle strength in patients undergoing clinical musculoskeletal rehabilitations. However, to our knowledge, no evidence examining the effectiveness of BFR training combined with rehabilitation (R) program on clinical outcome measures in athletes with CAI has been found. Therefore, this study aimed to evaluate the effects of supervised rehabilitation program with and without BFR on muscle strength, cross-sectional area (CSA), EMG activity, dynamic balance, and functional performance in athletes suffering from CAI. A total of 28 collegiate athletes with CAI (male and female) voluntarily participated in this study. They were randomly assigned either to the BFR+R (n=14) or the R group (n=14). Both groups underwent a supervised rehabilitation 3 times weekly for 6 consecutive weeks. The BFR+R group was applied with a cuff around the proximal thigh at 80% of arterial occlusion pressure in addition to R program, while the R group received the sham-BFR only. Before and after 4- and 6- week of intervention, isokinetic muscle strength, CSA, EMG activity, Y-balance test (YBT), and side hop test (SHT) were measured. The results demonstrated that both BFR+R and R groups displayed significant improvements in concentric peak torque of hip extensor and abductor, eccentric peak torque of ankle evertor, increased EMG activities of gluteus maximus and gluteus medius in all directions, fibularis longus in posteromedial and posterolateral directions, and tibialis anterior in anterior directions during performing YBT, along with improved SHT timed performance over a 6-week intervention, compared with baseline (all, P<0.05). In addition, the BFR+R group produced superior benefits over the R group for all above variables examined. Nevertheless, there were non-significant differences in reaching distances and COP measures observed between groups during post-intervention. The present finding indicated that including BFR training to traditional rehabilitation over 6 weeks appears to be more effective in improving muscle strength, CSA, muscle activation, and functional performance, but does not further enhance dynamic postural balance, compared with the tradition rehabilitation alone. This information could be alternative implications for physical therapists and sports medicine practitioners when designing rehabilitation program for athletes with CAI.