High-Intensity Interval Training (HIIT) Progressive Sprint-Release Model: Its Effect in Increasing Speed, Aerobic Capacity, and Anaerobic Capacity of Athletes

Physical abilities is one of the most important aspects influencing an athlete's competitive success. This research aims to determine the effect of the High-Intensity Interval Training (HIIT) Progressive Sprint-Release model in increasing athletes' speed, aerobic capacity, and anaerobic capacity. The research method used is quasi-experimental quantitative research with a research design, namely a randomized pretest-posttest group design. Purposive sampling technique was used to determine research subjects with the criteria of female rugby athletes aged 18 -22 years, exercising regularly six times per week, healthy, and without injuries. There were 20 athletes who were willing to be research subjects and were divided into two groups randomly, namely 10 athletes in the group that underwent the High Intensity Interval Training (HIIT) treatment with the Progressive Sprint-Release (PSRG) model and 10 other athletes in the control group (CG). Progressive Sprint-Release model HIIT treatment for 8 weeks with training frequency 3 times a week. The research instruments used were a 20-meter sprint to measure speed, an MFT to measure aerobic capacity, and a 300-meter sprint to measure anaerobic capacity. Data analysis technique used was the paired sample t -test and the independent sample t -test, and SPSS software version 25 was used. The results of the paired sample t -test, which compared the pre-test with the post -test in the PSRG group (pre-test vs. post -test), showed a significant increase in speed (3.99 +/- 0.231 vs. 3.87 +/- 0.253 seconds, p<0.05), aerobic capacity (29.23 +/- 4.026 vs. 31.81 +/- 4.346 ml/kg/min, p<0.05), and anaerobic capacity (75 +/- 9.821 vs. 63.6 +/- 6.736 seconds, p<0.05). The results of the independent sample t -test showed that there were significant differences between PSRG and CG in speed (p<0.05), aerobic capacity (p<0.05), and anaerobic capacity (p<0.05). In conclusion, the HIIT Progressive Sprint-Release model can increase speed, aerobic capacity, and anaerobic capacity.