Gait stability of diabetic patients is altered with the rigid rocker shoes.

BACKGROUND: Rigid-rocker shoes may induce gait instability in diabetics, however, this is not clearly investigated. The present study investigates if rigid-rocker shoes influence diabetic gait stability. METHODS: Fourteen non-neuropathic and nine neuropathic diabetics, plus eleven healthy young-adults were recruited. Full-body kinematic data was captured during walking. Experimental conditions included barefoot and three rocker-shoe designs according to the rocker angle, apex angle and apex position (R10: 10°, 80°, 60%; R15: 15°, 95°, 52%; R20: 20°, 95°, 60%). Sagittal and frontal stability margin, plus fear of fall were main outcome measures. FINDINGS: Sagittal stability margin was not affected by health, however, was increased with R10 and R15 in non-neuropathic diabetics and healthy individuals (R2 = 0.16). Variability of sagittal stability margin was not altered in neuropathic diabetics, but was increased with R15 and R20 in healthy participants, with R15 in non-neuropathic diabetics (R2 = 0.12). Frontal stability margin (R2 = 0.46) and its variability (R2 = 0.39) were significantly increased in neuropathic and non-neuropathic diabetics compared to healthy individuals. Frontal stability margin was significantly higher with R15 in neuropathic diabetics, and with R20 in both non-neuropathic and healthy participants. Sagittal and frontal stability margin were strongly correlated with fear of fall in neuropathic diabetics. INTERPRETATIONS: R15 and R20 might challenge gait stability of diabetics cause them restrict centre of mass motion thereby imposing a tighter control over walking. However, neuropathic diabetics generally walk very cautious due to neuropathy and increased fear of fall. Frontal stability margin, highly affected by health and experimental condition, is a more sensitive indicator of gait stability.

Effect of eccentric exercise-induced muscle damage on electromyographyic activity of quadriceps in untrained healthy females.

BACKGROUND: The aim of this study was to investigate muscle damage indicators and electromyography activities of quadriceps muscles at 25° of hip flexion in untrained healthy females after an eccentric exercise induced muscle fiber damage. METHODS: A total of 14 healthy females participated in this pre-experimental study. The subjects performed maximal eccentric quadriceps contractions at 25˚ of hip flexion. Maximum voluntary extensor isometric and concentric moments, angle of maximum moment for concentric contractions, perceived pain intensity, and pain pressure threshold were examined before, immediately, 48 hours, 120 hours and 14 days after eccentric exercise. Additionally, electromyography of three parts of quadriceps muscle, knee flexion range of motion and thigh circumference were measured before and after eccentric exercise. RESULTS: Significant reductions in maximum isometric moment and maximum concentric moment were observed at angular velocity of 60˚ per sec immediately after eccentric exercise (p<0.05). Both maximum isometric moment and maximum concentric moment recovered to the baseline 48 hours after eccentric exercise. Increased pain intensity and decreased knee joint range of motion manifested 48 hours after eccentric exercise. Pain pressure threshold for the quadriceps was higher 14 days after exercise as compared to 48 and 120 hours (p<0.05). No significant changes observed in electromyography and thigh circumference (p>0.05). CONCLUSION: Eccentric exercise performed at 25˚ of hip flexion resulted in muscle fiber injuries within the quadriceps muscle. However, electromyography of quadriceps muscle was not significantly different than the baseline. The result indicates that hip joint position may modify the effect of eccentric exercise on muscle activation.