Postural reactions following forward platform perturbation in young, middle-age, and old adults

Effect of exercise-induced fatigue on postural control of the knee

“…The EMG onset was estimated relative to the onset of platform movement using the signal processing method developed by Merlo et al (2003). To assess the amplitude of muscle activity during the postural perturbations, the average rectified value (ARV) of individual muscles was calculated over a window of 600 ms after the onset of platform movement (de Freitas et al, 2010). The ARV obtained for the eight trials were averaged to obtain a representative value for each muscle.…”

The Effects of a Perturbation-Based Balance Training on Neuromuscular Recruitment and Functional Mobility in Community-Dwelling Older Women

“…9 Despite results showing that the exercise regimen used in this study increased the muscle activity (EMG amplitude) during the disturbance test, these improvements were found only in the distal muscles, possibly due to the unstable surface training used for recruiting preferably ankle muscles, especially the TA. 1 Therefore, the neuromuscular enhancement of distal muscles obtained here may be important to improve postural control and possibly functional mobility in older adults. 1 Therefore, the neuromuscular enhancement of distal muscles obtained here may be important to improve postural control and possibly functional mobility in older adults.…”

“…All participants were evaluated by a perturbation test performed on a sliding apparatus constructed especially for this study, similar to that described by Freitas et al 1 The participants also performed the TUG test 15 and the central activation failure test of the ankle plantar fl exor and dorsifl exor muscles. 16 Data were collected at baseline (pretraining), after 6 weeks of balance training (posttraining), and after 6 weeks of detraining (postdetraining).…”

Reação postural de jovens e idosos ativos em teste de perturbação do equilíbrio

“…Alterações posturais, quase sempre presentes em idosos, também podem ter contribuído visto que tendem a aumentar o deslocamento do centro de massa que é projetado à frente, tornando-os mais propensos a desequilíbrios anteriores 18 . A influência da menor velocidade de ativação muscular em idosos 19 sobre o deslocamento e o tempo de reversão do centro de massa após uma perturbação parece ter sido mínima, uma vez que os aspectos temporais da ativação muscular podem desempenhar um papel menor no controle do deslocamento excessivo do centro de massa após perturbações 20 . Diferenças na carga aplicada não explicam as diferenças entre jovens e idosos, posto que a carga foi proporcional à massa corporal dos participantes 15 .…”