Acute physiological and hormonal changes of blood flow restriction in strength training

In the literature, the application of blood flow restriction; there is information about its positive effect on performance improvement. In this study; it was aimed to determine some hormones and physiological parameters that are effective on the strength development of athletes and their acute effects with blood flow restriction application. 14 healthy male participants who do sports at a professional level; performed the knee extension exercise with and without blood flow restriction as two different types of strength, quick strength 6 sets of 20 repetitions and maximal strength 3 sets of 5 repetitions. The trainings were carried out with and without restrictions, with a one-week break. The blood flow restriction cuff pressure adjustment was set at 160 mmHg for each athlete. In order to determine the acute hormonal and physiological changes of the athletes, 3 blood samples were taken in 3 different time periods [ (1) before exercise, (2) after exercise, (3) 24 hours after exercise] in each training protocol, and a total of 12 blood samples were taken from every athlete for each protocol. In all analyzes, α=0.05 was taken and for cases where a statistically significant difference was obtained, effect sizes calculated with partial eta square were included. The relationship between blood flow restriction practice and hormonal and physiological changes was tested with "three-way analysis of variance (ANOVA) for correlated (repeated) measurements". Statistical evaluation of the variables was evaluated with blood restriction*strength training*time interactions. The difference was statistically significant in all variables for growth hormone and IGF-1 (p<0.05). Although the CK and LDH measurements of the athletes differed according to blood-restricted and unrestricted training and time variables (p<0.05), they did not show significant differences in maximal strength and rapid strength training intensity (p>0.05). heart rate; interaction effect (blood restriction*strength training*time) was found to be statistically significant (F=10.295; p<0.05). There was no significant difference in oxygen saturation (F=0.802; p>0.05). The difference in systolic blood pressures was significant (F=3.538; p<0.05) and the difference in diastolic blood pressures (blood restriction*strength training*time) was statistically significant. was not found (F=0.320; p>0.05). According to the findings, it can be said that low-intensity blood flow restriction practice has higher averages than high-intensity resistance exercises in the variables that affect performance development. Keywords: Blood flow restriction, Hormone, Strength.