Optimizing Performance: Minimal Eccentric Overload Training

Traditional resistance training (TRT) typically involves concentric (CON) and eccentric (ECC) actions, usually performed with equal loads. However, research has shown that muscles can exert significantly higher forces during the ECC phase. Thus, TRT often fails to fully stimulate muscles during the ECC phase. Accentuated eccentric loading (AEL) addresses this by applying higher loads during the ECC phase and reducing the load for the CON phase. AEL has already been shown to greatly improve neurology and morphology in muscles and tendons while enhancing muscle strength and power more effectively than TRT. In addition, minimal-dose strategies have also been explored in TRT, showing that even low training frequencies with moderate loads can maintain or slightly increase strength. Thus, a minimalistic approach with AEL might be beneficial in sports such as soccer, where time-efficient training methods are greatly needed during the competitive season. We hypothesize that 24 weeks of a minimalistic AEL training program will result in changes in functional and morphological muscle and tendon properties, which can be explained by the high effectiveness of ECC overloading. Moreover, AEL training will be superior, compared to the TRT group, in most of the measured parameters. This project aims to evaluate the impact of a minimalistic, supervised AEL resistance training program on muscle strength, hypertrophy, and various performance parameters in soccer players. Participants will engage in a 24-week training program, divided into groups that will either complete one session per week with five repetitions and a single set (AEL1) or three sets (AEL3) of squats, utilizing an ECC overload of up to 130% of their one-repetition maximum (1RM) and 70% of the 1RM during the CON phase. In addition, two traditional resistance training groups will perform identical protocols, completing either one session per week with five repetitions and a single set (TRAD1) or three sets (TRAD3) under similar CON-ECC loading conditions of up to 90% of the 1RM. A control group will be included for comparative purposes. Secondary outcomes will include assessments of lower extremity morphological and functional changes in the vastus lateralis muscle, and structural changes in the patellar tendon. This research will be the first investigation to provide insights into the efficiency of AEL as a minimalistic yet effective approach to resistance training, and aims to detect a dose-dependent relationship, potentially offering a promising time-efficient alternative to TRT protocols.