HIGH-INTENSITY TRAINING IMPROVES EXERCISE PERFORMANCE IN ELITE WOMEN VOLLEYBALL PLAYERS DURING A COMPETITIVE SEASON

Elite women volleyball players (n = 25; mean +/- SD: age, 19 +/- 5 years; height, 171 +/- 7 cm; weight, 63 +/- 10 kg) volunteered to participate in the study. They were randomized into a high-intensity training (HIT; n = 13) group and a control (CON; n = 12) group. In addition to the normal team training and games, HIT performed 6-10 x 30-seconds all-out running intervals separated by 3-minute recovery periods 3 times per week during a 4-week in-season period whereas CON only completed the team training sessions and games. Preintervention and postintervention, all players completed the arrowhead agility test (AAT), a repeated sprint test (RST; 5 x 30 meters separated by 25 seconds of recovery), and the Yo-Yo Intermittent Recovery level 2 test (Yo-Yo IR2) followed by a-10 minute rest period and the Yo-Yo IR1 test. Mean running distance during HIT in week 1 was 152 +/- 4 m and increased (p <= 0.05) by 4.6% (159 +/- 3 m) in week 4. The AAT performance improved (p <= 0.05) by 2.3% (18.87 6 0.97-18.44 +/- 1.06 seconds) and RST by 4.3% postintervention in the HIT group only. Baseline RST fatigue index was 7.0 +/- 2.9 and 6.2 +/- 5.0% in HIT and CON, respectively, but was lowered (p <= 0.05) to 2.7 +/- 3.0% posttraining in HIT and remained unaltered in CON (5.5 +/- 5.0%). In HIT, Yo-Yo IR2 and Yo-Yo IR1 performance improved by 12.6 and 18.3% postintervention, respectively, with greater (p <= 0.05) Yo-yo IR1 change scores than in CON. In conclusion, additional high-intensity in-season training performed as interval running improved agility, repeated sprint ability, and high-intensity intermittent exercise performance in elite women volleyball players.