Author(s): CHMURA, P., OLIVA-LOZANO, J.M., WEI, X., KRUSTRUP, P., Institution: WROCLAW UNIVERSITY OF HEALTH AND SPORT SCIENCES, Country: POLAND, Abstract-ID: 2234

INTRODUCTION:
The preparation period is a key time when players returning from a rest break are expected to improve their physical performance quickly and substantially in order to compete in a league lasting many weeks (Csala et al. 2021). The aim of this study was to investigate how the anaerobic threshold (ANT) and psychomotor fatigue threshold (PFT) change with the insertion of the 30-min block of high intensity interval training (HIIT) and normal training implemented during the preparatory period.
METHODS:
Twenty selected U-19 players playing daily in a professional football team were studied. The team was randomly divided by a group of players. The first group realized two times per week a 30-min block of HIIT exercises (HIIT), and the second group realized normal training (CON). The research was carried out in the Exercise Research Laboratory. The players performed an incremental progressive all-out test at the beginning of the round and after the preparatory period lasting 4 weeks. The measurement of lactate (LA) determined anaerobic threshold (ANT), whereas the choice reaction time (CRT) indicated psychomotor fatigue threshold (PFT) among other selected physiological parameters. The repeated-measure analysis of variance (ANOVA) compared mean values for the examined variables using the Fisher post hoc test.
RESULTS:
One of our main results is that the applied loads in the HIIT group significantly raised the anaerobic threshold at the velocity running from 13.20 to 14.49 km/h (p ≤ 0.000). In contrast, the CON group did not show any significant change, remaining at 13.26 km/h before and 13.20 km/h after the 4-week preparation period. Regarding the psychomotor fatigue threshold, the HIIT group initially reached 14.00 km/h, and after the preparation period, it significantly increased to 15.44 km/h (p ≤ 0.000). While the CON group also showed an increase, it was not statistically significant (from 13.75 to 14.12 km/h).
CONCLUSION:
One advantage of HIIT is its ability to improve physiological parameters and performance in a short amount of time (Buchheit and Laursen 2019). Finally, it was shown that the group performing an additional 30-minute block of interval training tested thresholds shifted towards higher loads - higher running speed. In addition, no significant changes were observed in the control group. This indicates that coaches should incorporate HIIT exercises in the preparatory period.
References:
1. Csala et al. (2021)
2. Buchheit and Laursen (2019)