RESUMO
OBJECTIVE: The aim of this study was to compare the immediate effects of standard physiotherapy (S) and balneotherapy (B) on the postural capacity of subjects with lower-limb injuries. METHODS: The postural sway of 12 voluntary subjects was evaluated before (REF1 and REF2) and after two different physiotherapy sessions performed in the swimming pool (B) or under (S). The centre of pressure (CP) trajectory was recorded by use of a force platform. CP displacements in the mediolateral and anteroposterior axes were then separated into two elementary superimposed components: the horizontal motion of the centre of gravity (CG) and the difference between the CP and the vertical projection of the CG (CP-CG). The amplitude of the latter component (CP-CG) is thought to express neuromuscular activity. All trajectories were then analysed in terms of classical and frequency parameters. RESULTS: Postural sway did not differ before and after the physiotherapy sessions. Following both sessions, the mean CG velocity decreased significantly (P<0.5). The area of CP-CG trajectory was diminished solely by the aquatic exercise (P<0.5) and was associated with decreased amplitude of motion along the anteroposterior axis (P<0.05), which suggests decreased neuromuscular activity to maintain posture. CONCLUSION: Interestingly, decreased motion was observed along the anteroposterior axis, which corresponds to ankle movements. Exercising lower-limb muscles under water could reinforce proprioceptive input, resulting in a better postural control.