INTRODUCTION: Strength and conditioning (S&C) coaches in youth soccer actively seek to improve sport specific actions, such as acceleration, sprinting and jumping, through a variety of training methods, of which resistance training (RT) is a central component [1]. However, recently published research suggests that soccer S&C coaches typically implement three sets of eight repetitions at a moderate intensity, when aiming to develop strength in-season. Further, from this PhD project, two limiting factors reported by S&C coaches for incorporating RT into their programmes are time constraints and concerns regarding delayed onset muscle soreness (DOMS) following RT. The aims of this study were to investigate the impact of high- vs. moderate-intensity RT vs. pitch-based soccer training only on changes in strength, power, and speed, and to compare DOMS between training groups in male academy soccer players (ASP). METHODS: Twenty-two ASP (18±1 years-old) were assigned to either a high-intensity RT (HRT: n=8), moderate-intensity RT (MRT: n=7) or a soccer training-only control group (CON: n=7). HRT completed 2x4 parallel back squat (PBS) repetitions at 90% single-repetition maximum (1RM), while MRT performed 3x8 PBS repetitions at 80% 1RM, both once a week for six-weeks in-season alongside regular soccer training. CON performed pitch-based soccer training only for six weeks. All groups completed the following pre- and post-training assessments: 3RM PBS; bilateral vertical and horizontal countermovement jump (CMJ) height/distance; squat jump (SJ) height; and 20m sprint. DOMS was assessed via visual analogue scale after each training session throughout the six-week period. RESULTS: HRT and MRT experienced similar increases compared to CON in absolute PBS 3RM (+16±8% vs. +27±16% vs. +2±3%, p<0.001), SJ height (+6±6% vs. +11±7% vs. -7±6%, p=0.001), CMJ height (+8±3% vs. +10±6% vs. -4±10%, p=0.008) following training. Further, there was a greater increase in PBS 3RM relative to body mass following HRT than MRT and CON (+23±8% vs. +16±14% vs. +3±4%, p=0.001) and horizontal CMJ distance improved in HRT but not in MRT or CON (+11±5%, +7±7% and +2±4%, respectively, p=0.011). Sprint time did not change in any group (p>0.05). HRT volume was 58±15% lower than that of MRT (p<0.001) and DOMS measured throughout training did not differ between groups (p=0.487). CONCLUSION: These findings suggest that one HRT session a week is an efficient method to improve lower-limb strength and power in ASP in-season compared to MRT and pitch-based soccer training only. Importantly, HRT achieved this with 58% less training volume than MRT, and similar DOMS to soccer training alone, thus highlighting the effectiveness of HRT and supporting its incorporation into a standard in-season ASP training programme.
© Copyright 2022 27th Annual Congress of the European College of Sport Science (ECSS), Sevilla, 30. Aug - 2. Sep 2022. Veröffentlicht von Faculty of Sport Science - Universidad Pablo de Olavide. Alle Rechte vorbehalten.