Enhancing muscle strength and body composition after low-load resistance with blood flow restriction and hypoxia in untrained males

Introduction: High-intensity resistance training may elevate the risk of musculoskeletal injuries and hinder optimal performance execution. Objective: This study compared the effects of low-load resistance training under blood flow restriction (BFR) and hypoxia (HYP) on body composition, strength, and endurance in untrained male college students. Methodology: Forty-five male college students from Ubon Ratchathani Rajabhat University were purposively sampled and matched into three groups (n = 15): 1) high-load resistance training (HLRT), 2) low-load resistance combined with blood flow restriction training (LLBFR), and 3) low-load resistance combined with hypoxic training (LLHYP). All groups trained three times weekly for five weeks. Results: After five weeks of training, all groups showed significant improvements in fat-free mass, skeletal muscle mass and performance outcome (p < 0.05). The LLHYP group also exhibited significantly reduced skinfold thickness and greater arm circumference (p < 0.05). All groups improved strength and endurance, but LLHYP demonstrated significantly greater endurance than HLRT in both exercises (p = 0.021 and 0.003, respectively) and outperformed LLBFR in the dip machine (p = 0.032). Discussion: Findings support that LLBFR and LLHYP can produce similar strength and body composition outcomes as HLRT over a short term. LLHYP, in particular, showed superior benefits in endurance, possibly due to hypoxia-related physiological adaptations. Conclusions: Low-load resistance training with BFR and HYP effectively enhanced body composition, strength, and endurance of the biceps and triceps. This approach may offer a safer alternative for untrained male students.