Comparative Effects of Low-Load Resistance Exercise with Blood Flow Restriction Versus High-Load Resistance Training on Wrist and Grip Strength and Forearm Hypertrophy in Male University Students: A Randomized Controlled Trial

Abstract

Background: Blood flow restriction training permits resistance exercise at comparatively low external loads and may therefore provide a practical alternative when reduction of mechanical loading is desirable. Evidence specifically examining wrist and forearm musculature remains limited. Objective: To compare low-load blood flow restriction training with high-intensity resistance training for grip strength, multidirectional wrist strength, and forearm circumference in healthy male university students. Methods: In this parallel-group randomized controlled trial, 45 participants were randomized to BFRT (n=22) or HIRT (n=23). BFRT was performed at 20–30% of estimated 1RM with 50% limb occlusion pressure, whereas HIRT was performed at approximately 80% 1RM. Training was conducted three times weekly for eight weeks. Forty-two participants completed baseline, post-intervention, and four-week follow-up assessments and were analysed per protocol. Outcomes were analysed using 2×3 mixed-model ANOVA. Results: Grip strength increased from 34.75±3.00 to 40.78±3.24 kg in BFRT and from 33.90±2.77 to 40.07±2.73 kg in HIRT. The Group×Time interaction for grip strength was not significant (p=0.893). Interactions were also non-significant for wrist flexion (p=0.912) and extension (p=0.885). Radial and ulnar deviation and forearm circumference increased over time in both groups. Conclusion: Both interventions produced substantial strength improvements. No differential longitudinal response was detected for the reported primary interaction analyses; therefore, the findings support BFRT as a lower-load strengthening strategy without establishing formal equivalence or non-inferiority to HIRT