EFFECTS OF HIGH-INTENSITY INTERVAL TRAINING WITH DIFFERENT INTERVAL DURATIONS ON PHYSICAL PERFORMANCE IN HANDBALL PLAYERS

The purpose of this study was to compare the effects of 2 highintensity interval training (HIIT) protocols with different interval durations (short [SI] vs. long [LI]) based on peak running velocity in 30-15 Intermittent Fitness Test (VIFT) in handball players. Eighteen highly-trained players (age: 22.7 +/- 3.9 years; height: 181.5 +/- 6.6 cm; body mass: 84.7 +/- 14.1 kg) were randomly assigned to SI (2 sets of 22 intervals of 10-second runs at 95% VIFT) or LI (5 sets of 3-minute intervals at 85% VIFT) group. The intervention program had to be carried out 2 times a week over 6 weeks. Before and after training period, 10-m sprint, countermovement jump, repeated sprint ability (RSA), and 30-15IFT were assessed. In the within-group analysis, significant improvements in VIFT were found in SI (8.18%) and LI (8.19%) from pretest to posttest. Players in both SI and LI also showed significant enhancements in RSA average time (effect size [ES] = 0.72 and 0.38, respectively), total time (ES = 0.72 and 0.38, respectively), and percentage of decrement (ES = 1.08 and 0.77, respectively) from pretest to posttest. Percentage changes in VIFT, for both groups combined, had a very large correlation with percentage changes in percentage of decrement of RSA (r = 0.857). In the between-groups, there were no differences between the training groups (SI and LI) in any variable (p < 0.05). These results indicate that both HIIT protocols are effective for fitness development during preseason period in handball players. However, SI should be considered as preferred HIIT method because of its higher specificity.