Reliable and effective novel home-based training set-up for application of an evidence-based high-loading stimulus to improve triceps surae function

• Published in: Journal of sports sciences 2021-12, Vol.39 (24), p.2786-2795
• Main Authors: Radovanović, Goran, Kunz, Jona, Bohm, Sebastian, Arampatzis, Adamantios, Legerlotz, Kirsten
• Format: Article
• Language: English
• Subjects: Achilles tendon; Adaptation; Contraction; Humans; Injury prevention; Intervention; Leg; Muscle contraction; muscle imbalance; Muscle strength; musculoskeletal rehabilitation; Reproducibility of Results; Resistance Training; tendon rehabilitation; Triceps surae muscle
• ISSN: 0264-0414; 1466-447X
• DOI: 10.1080/02640414.2021.1959981

High-loading interventions aiming for muscle-tendon adaptations were so far implemented in on-site facilities. To make this evidence-based stimulus more accessible, we developed an easy-to-use sling-based training set-up for home-based Achilles tendon and triceps surae muscle strength training and assessed its reliability and effectiveness in healthy men. To assess reliability (n=11), intra-class correlation (ICC) and root mean square (RMS) differences of isometric maximum voluntary contraction (MVC) of the plantar flexors were used. Effectiveness was tested in a controlled intervention trial (n=12), applying one-legged high-loading intervention for 3 months with our mobile set-up, while the contralateral/untrained leg served as control, and assessing plantar flexor MVC, drop (DJ) and countermovement jump (CMJ) height. Reliability was excellent between (ICC B =0.935) and within session (ICC W s=0.940-0.967). The mean RMS difference between and within sessions was 5.3% and 4.7%, respectively. MVCs of the trained/intervention leg increased by 10.2±7% (P=0.004) (dynamometry) and 30.2±22.5% (mobile set-up) (P=0.012). MVC of the untrained/control leg did not change (P>0.05). DJ height increased (P=0.025; D z =2.13) by 2.37±2.9cm. CMJ height (P>0.05) did not change. We recommend the evidence-based high-loading application with our novel home-based training set-up as reliable and effective improving strength and jump performance of the plantar flexor muscle-tendon unit.