Adaptations of blood fluidity markers to progressive resistance training in men

Background Epidemiological evidence suggests that endurance training improves musculoskeletal health and influence blood parameters, but the effects of RT were less clear. Objective The present study investigated the effect of 12-weeks of RT on resting (pre-exercise) values and responses of blood fluidity parameters to a resistance exercise trial (RET). Methods Eighteen untrained males (Mean ± SD; age, 24.8 ± 1.2 years) were randomly assigned to training ( n = 10) or control ( n = 8) groups. Subjects in the training group performed a 12-week progressive RT program with 4 sessions per week. The training program consisted of three distinct phases: adaptation, hypertrophy, and strength, increasing intensity from 40–50% to 80–85% of their one-repetition maximum (1RM). Prior and after the 12-week program, both groups underwent a RET. Blood samples were taken before and after each RET. Results Significant ( p < 0.05) increases in blood viscosity, plasma viscosity, plasma fibrinogen, and hematocrit were found following the acute RET. However, neither the resting values nor responses to RET were affected by RT. Interestingly, 12 weeks of progressive RT attenuated responses of RBC indexes significantly ( p < 0.05). Conclusions The study concluded that although 12 weeks of RT does not alter resting blood fluidity, it reduces the acute changes in RBC indexes during high-intensity resistance exercise.