INTRODUCTION: The inclusion of isometric training (ISO) has been reported to improve strength and the performance various sports related skills (Lum and Barbosa, 2019; Lum et al., 2021). However, no study has compared the adaptations to long term (>24 weeks) and periodic inclusion of ISO. The aim of the study was to compare the effects of including isometric training for consecutive 24 weeks (CISO) against a periodic inclusion (PISO) of this mode of training, on strength and dynamic performances. METHODS: 24 elite floorball athletes (age: 23±2.7 years, stature: 1.74±2.08 m, body mass: 72.7±14.4 kg) were randomly assigned to the control (CON), CISO, or PISO group. Athletes completed 20-m sprint, countermovement jump (CMJ) and isometric mid-thigh pull (IMTP) during pre-test and were tested on week 6, 12, 18 and 24. All groups performed a similar strength training program twice per week. However, two sets of squats were replaced with isometric squat in CISO for all 24 weeks, but only on weeks 1-6 and 13-18 for PISO. RESULTS: A significant main effect for time was observed for 5-, 10-, and 20-m sprint time, CMJ height, peak force, peak power, time to take-off, modified reactive strength index, IMTP peak force, relative peak force and force at 200 ms (P= <0.001-0.037). CISO resulted in greater improvement in 5-m sprint time than CON at week 24 (P=0.024, g=1.17). Both CISO and PISO resulted in greater improvements in 10-m sprint time than CON at various time points (P=0.007-0.038 and 0.038, g=1.07-1.44 and 1.18, respectively). CISO and PISO resulted in greater improvements in 20-m sprint time than CON at week 6 (P=0.007 and 0.025, g=1.65 and 1.40, respectively). While no significant difference in percentage change in CMJ height between groups, a small to large effect was observed in favour of CISO as compared to CON (P=0.179, g=0.90) and PISO (P =0.542, g=0.49) at week 24. Similarly, no significant difference in the change in all IMTP measures. However, a moderate effect in favour of CISO and PISO as compared to CON was observed for IMTP peak force (P =0.413, g=0.58 and P=0.560, g=0.56, respectively) at week 24. CONCLUSION: The current results support the findings of previous studies, indicating that the inclusion of ISO is beneficial to both strength and dynamic performance as compared to dynamic resistance training alone. However, while CISO seems to result in greater positive effect on 20-m sprint and CMJ performance, there was no clear difference on its effect on maximal strength as compared to PISO.
© Copyright 2022 27th Annual Congress of the European College of Sport Science (ECSS), Sevilla, 30. Aug - 2. Sep 2022. Julkaistu Tekijä Faculty of Sport Science - Universidad Pablo de Olavide. Kaikki oikeudet pidätetään. / Kääntänyt https://www.DeepL.com/Translator