Plantar cooling does not affect standing balance: A systematic review and meta-analysis

The purpose of this systematic review with meta-analysis was to critically appraise and synthesize the literature to determine if cooling the plantar surface of the foot is an effective method of inducing postural control alterations in healthy individuals. Specific variables that were evaluated within the meta-analysis included (1) the duration of the plantar cooling intervention, (2) the stance type during postural control assessment, and (3) the role of visual input. A computerized search of four electronic databases from inception to March 2015 was performed to identify studies which examined the effects of plantar cooling on postural control in healthy individuals. A critical appraisal of the methodological quality of the included studies was performed using an appraisal criteria instrument previously used for assessing biomechanics studies. The literature search yielded 88 references of which 7 were deemed relevant and included in the systematic review and meta-analysis. A single, overall random-effects model meta-analysis of all study variables were performed; as well as, separate meta-analyses for each study variable. Across the 7 studies, the overall effect was 0.028 (95% CI = -0.177, 0.234; p = 0.78) indicating that cooling the plantar surface had a very small effect on postural control. Similar results were obtained when data were examined based on study quality, plantar cooling intervention duration, stance type during postural control assessment, and the presence of visual input. Therefore, cooling the plantar surface of the foot had a very weak, non-significant effect on standing balance despite the anesthetic effects identified in each study.