Effect of 4 Weeks of Anti-Gravity Treadmill Training on Isokinetic Muscle Strength and Muscle Activity in Adults Patients with a Femoral Fracture: A Randomized Controlled Trial

This study aimed to identify the effect of anti-gravity treadmill training on isokinetic lower-limb muscle strength and muscle activities in patients surgically treated for a hip fracture. A total of 34 participants were randomly assigned into two groups: anti-gravity treadmill training group (<i>n</i> = 17) and control group (<i>n</i> = 17). The isokinetic muscle strength and endurance of hip flexor and extensor and the activities of the vastus lateralis (VL), vastus medialis (VM), gluteus maximus (GM), and gluteus medialis (Gm) muscles were measured before and after 4 weeks of the interventions. Significant improvements were observed in isokinetic muscle strength and endurance of hip flexors and extensors in both groups (<i>p</i> < 0.05); however, no significant differences were observed between the groups (<i>p</i> > 0.05) except for muscle strength of the hip extensor (<i>d</i> = 0.78, <i>p</i> = 0029). Statistically significant increases in the muscle activity of VL, VM, GM, and Gm were found before and after the intervention (<i>p</i> < 0.05), and significant differences in muscle activities of GM (<i>d</i> = 2.64, <i>p</i> < 0.001) and Gm (<i>d</i> = 2.59, <i>p</i> < 0.001) were observed between the groups. Our results indicate that both groups showed improvement in muscle strength, endurance, and activities after the intervention. Additionally, anti-gravity treadmill training improved significantly more muscle strength at 60°/s of the hip extensor and gluteus muscle activities than conventional therapy, which may be appropriate for patients with hip fracture surgery.