EFFECTS OF BLOOD FLOW RESTRICTION RESISTANCE TRAINING ON STRENGTH GAINS AND ARM DIAMETER

Abstract

Resistance training (RT) is widely used for its benefits, such as increased muscle strength and hypertrophy. However, performing RT with high loads (60–80% of 1RM) imposes joint stress, limiting its application in vulnerable populations. As an alternative, blood flow restriction training (Kaatsu Training), performed with lower loads (20–50% of 1RM), promotes metabolic adaptations and strength gains with reduced joint stress. This study aimed to analyze the effects of blood flow restriction strength training on muscle strength and arm diameter in trained young men. An experimental, longitudinal, and quantitative study was conducted with 11 men (aged 20–34) who regularly practiced RT. Participants were randomly assigned to two groups: Control (traditional training) and Intervention (training with blood flow restriction). The intervention lasted eight weeks (three weekly sessions), with strength (1RM) and arm circumference assessed before and after the intervention. Results showed significant strength gains in both groups: Control (+10.20%) and Intervention (+8.68%), with no statistical difference between them. No significant changes in muscle circumference were observed; both groups showed a slight average reduction in arm diameter. Analysis of covariance indicated that the type of training did not significantly influence strength gains or morphological changes, with initial performance being the main predictor of post-intervention outcomes. It is concluded that blood flow restriction strength training is effective in promoting strength gains with reduced loads and lower joint stress, representing a viable alternative for individuals with limitations to conventional training. However, the absence of hypertrophy suggests the need for longer studies with greater control of external variables to better clarify its morphological effects.