Postural control during quiet standing: impact of stance variation, sex, and body composition

Assess the impact of different stance variations, body composition and use of shoes among healthy young men and women on postural sway during quiet stance.

A repeated-measures study with 123 participants (40 males, 83 females) aged 18-39 years was conducted. Participants stood quietly without shoes on a force plate with hands on hips (also performed with shoes), hands by sides, arms across chest, hands behind head and while isometrically contracting. Postural sway metrics were assessed for each condition. Body composition was assessed using bioelectric impedance analysis.

There were no significant differences found between stances involving hands on hips, arms across chest, hands behind head, or hands by sides in the measured variables. Postural sway was greatest during isometric contraction (p < 0.05). Women had greater path length, sway frequency and greater anterior-posterior sample entropy (AP SampEn) compared to men (p < 0.05). Quiet stance postural sway was not influenced by the use of shoes. Variables related to lean body mass are significantly associated with postural sway as assessed by principal component analysis.

The assessment of quiet standing postural control in healthy young adults can use a variety of stance variations (with or without shoes) since they yield statistically similar measures of postural sway. Postural sway is significantly increased with muscle contraction. Young women exhibit greater path length, sway frequency and AP SampEn compared to young men. Lean body mass may represent a target for improved postural control since it is associated with postural sway.