Clinical Research Directory

Effects of Eccentric Training at Long Muscle Length on Functional Capacities of Elderly Adults

As aging leads to a decline in muscle function and overall physical performance, interventions targeting muscle strength and neuromechanical properties are critical for maintaining functional independence in older adults. Long-length eccentric training has shown promise in enhancing muscle performance, but its effects in older adults, particularly in a home-based setting, remain underexplored. The aim of this trial is to assess whether a targeted home-based training intervention incorporating long-length eccentric contractions can enhance functional capacity and neuromechanical properties in healthy older adults. Participants will be semi-randomly allocated to one of two groups: an experimental group incorporating long-length eccentric contractions (Group 1) or a conventional resistance training group (Group 2), with group assignment stratified to ensure an equal number of men and women in each group. Each participant will complete three laboratory-based experimental sessions (i.e., two Pre-training sessions and one Post-training session) , during which five key evaluations will be conducted: (i) the 5-Time Sit to Stand test, serving as the primary outcome measure; (ii) the Timed Up and Go test; (iii) assessments of isometric and dynamic muscle strength in the knee extensors and plantar flexors; (iv) measurements of the cross-sectional areas of the vastus lateralis, rectus femoris, gastrocnemius medialis, and soleus muscles; and (v) evaluation of tendon stiffness. Following the pre-evaluation, each participant will engage in a 24-session, semi-supervised, home-based training protocol over a period of 8 to 11 weeks. The training program will include eight exercises, with four targeting the upper limbs and four focused on the lower limbs. Group 1 will perform the lower limb exercises at long muscle lengths, while Group 2 will perform the same exercises in a conventional manner (i.e., at neutral or shorter muscle lengths). The total training volume (calculated as repetitions × sets, in arbitrary units) will be matched across both groups, ensuring that any observed differences in outcomes are attributable to the specific training modality rather than differences in workload.