Effects of electrically stimulated muscle contractions on bone loss & muscle atrophy

Exposure to the disuse environment affects a wide range of populations and severely debilitates musculoskeletal function. Non-invasive therapeutic treatments are essential to prevent bone loss and muscular atrophy. Electrically stimulated muscle contractions have been suggested as a treatment mechanism to prevent disuse induced bone loss and muscle atrophy. Understanding the treatment mechanism is essential before validation and optimization. The overall objective of this study was to evaluate the effects of muscle stimulations at varying frequencies in the mouse functional disuse model. Muscle contraction stimulations were compared at 1 Hz and 20 Hz loading frequencies. Quadriceps muscle contractions were stimulated in a disuse mouse model for 10 minutes a day for 3 weeks, and the stimulated groups were compared with baseline, age-matched, disuse control groups. Hind limb muscle wet weights revealed 9% recovery of soleus muscle mass in animals stimulated with 20 Hz frequencies. Similarly, micro-computed tomography revealed 18% recovery of trabecular bone volume in the distal femur of animals stimulated with 20 Hz frequencies. The inter-dependent relationship between muscle pump contractions and bone quantity suggest muscle contraction stimulations as a therapeutic treatment for disuse induced musculoskeletal atrophy.