The purpose of this study was to compare the effects of galvanic vestibular stimulation (GVS) on postural control for participants of different physical activity status (i.e. active and non-active). Two groups of participants were recruited: one group of participants who regularly practised sports activities (active group, n = 17), and one group of participants who did not practise physical and/or sports activities (non-active group, n = 17). They were compared in a reference condition (i.e bipedal stance with eyes open) and four vestibular manipulation condition (i.e. GVS at 0.5 mA and 3 mA, in accordance with two designs) lasting 20 seconds. The centre of foot pressure displacement velocities were compared between the two groups. The main results indicate that the regular practice of sports activities counteracts postural control disruption caused by GVS. The active group demonstrated better postural control than the non-active group when subjected to higher vestibular manipulation. The active group may have developed their ability to reduce the influence of inaccurate vestibular signals. The active participants could identify the relevant sensory input, thought a better central integration, which enables them to switch faster between sensory inputs.

The purpose of this study was to compare the effects of proprioceptive disruption on postural control for participants of different ages according to their physical and/or sport activity levels. Two groups of young and old participants who practiced chronic physical and/or sport activities (young active [n = 17; average age 20.5 +/- 1.1 yr] and old active [n = 17; average age 74.0 +/- 3.8 yr]) and two groups of young and old participants who did not practice physical and/or sport activities (young sedentary [n = 17; average age 20.0 +/- 1.3 yr] and old sedentary [n = 17; average age 74.7 +/- 6.3 yr]) participated in the study. They were compared in a bipedal quiet stance reference condition and a bilateral Achilles tendon vibration condition. Center of foot pressure displacements and frequency analysis were compared between the groups. The results indicated that when proprioceptive information was disrupted, the postural control disturbance was more important for the old sedentary group than for the other groups. There were no differences between the old active group and the young sedentary group. Postural control was less altered for the young active group than for the other groups. Aging decreases the efficiency of postural control regardless of the assessment conditions. Physical and sport activities may compensate for the disturbing effects of proprioceptive perturbation through a better use of sensory information whatever the age of the participants.

The current literature shows no consensus regarding the difference between the dominant leg (D-Leg) and the non-dominant leg (ND-Leg) in terms of postural control. This lack of consensus could stem from motor experience (i.e., symmetric or asymmetric motricity) and/or the physiological state induced by physical exercise. This study aimed to investigate the acute effects of fatiguing exercise on postural control when standing on the D-Leg and the ND-Leg, in athletes practicing symmetric (SYM) and asymmetric (ASYM) sports. Thirty healthy male participants were recruited and divided into two groups, (SYM n = 15) and (ASYM n = 15, on the basis of the motricity induced by the sport they practice. Monopedal postural control was assessed for the D-Leg and the ND-Leg before and after the fatigue period (which consisted of repeating squats until exhaustion). A force platform was used to calculate the spatio-temporal characteristics of the displacements of the center of foot pressure (COP). A significant fatigue effect was observed in both groups on the D-Leg and the ND-Leg for all the COP parameters. There was a tendency (p = 0.06) between the ASYM and SYM groups on the D-Leg, concerning the relative increase in the COP velocity in the frontal plane after the fatigue period. The fatigue condition disturbed postural control in both the SYM and ASYM groups on the D-Leg and ND-Leg. This disturbing effect related to fatigue tends to be more marked in athletes practicing asymmetric sports than in athletes practicing symmetric sports on the D-Leg.