Effect of si̇rkadyen rhythm on aerobic and anaerobic performance in athletes

The aim of the study was to investigate the effect of exercise at different times of the day and to look at the adaptation process between them. The research was conducted on male students studying at Bayburt University Faculty of Sports Sciences with the voluntary participation of 45 participants in total, including 15 morning exercise group (SEG), 15 evening exercise group (AEG) and 15 control group (CG). Forty-five male athletes (Age: 20.93±0.37; Body Weight: 71.28±0.98; Height: 1.77±0.015) participated in the study. Participants performed circuit training for 45 days to develop aerobic and anaerobic capacity. The workouts were determined as (Monday, Wednesday and Friday). Participants took a pre-test before starting the training, a mid-test after 15 days and a post-test at the end of 45 days. Cooper test, Vertical jump, T-test, Body temperature, Blood pressure, Heart rate (HR), Body temperature, Blood pressure, Heart rate (HR) were taken before starting the training, between and at the end of the training. The data obtained in the study were analyzed using IBM SPSS (Statistical Package for the Social Sciences) 24.0 program. Descriptive statistical tests (Mean, Minimum, Maximum, Standard Deviation) were applied in the evaluation of demographic data. Normality distribution of the data was tested with shapiro wilk test. Differences between normally distributed variables in related groups were determined by one-way anova and non-normally distributed variables were determined by Wilcoxon ranked sign. In unrelated groups, differences between normally distributed variables were determined by repeated measures anova and non-normally distributed variables were determined by Kruskal Wallis H test. Statistically significant difference was accepted as p<0.05. As a result of the analyzes, a significant difference was found in SEG Cooper and vertical jump in the measurements taken in the morning of the pre-interim and post-test, while a significant difference was found in AEG cooper, body temperature, HR and blood pressure at p<0.05 level. In the measurements taken in the evening, a significant difference was found in the Cooper test of the SEG and AEG group, while a significant difference was found in CG blood pressure and HR at p<0.05 level. In the pre-test morning measurements, significant differences were found in Cooper and blood pressure, while in the evening measurements, significant differences were found in Cooper, vertical jump, body temperature and blood pressure at p<0.05 level. In the morning measurements of the intermediate test, significant differences were found in Cooper, t-test, vertical jump, body temperature and HR, while in the evening measurements, significant differences were found in Cooper test, vertical jump and body temperature at p<0.05 level. In the post-test morning measurements, Cooper test, t-test, vertical jump, body temperature and HR were significantly different, while in the evening measurements, t-test, vertical jump, body temperature and HR were significantly different at p<0.05 level. As a result, it can be said that the morning exercise group and evening exercise groups showed a statistically significant difference in aerobic and anaerobic performances by showing the effect of circadian rhythm in line with the training performed on the athletes, while no significant difference was found on the control group. Keywords: Aerobic, anaerobic, circadian rhythm, performance.