BACKGROUND: In older adults, diminished balance is associated with reduced physical functioning and an increased risk of falling. This is an update of a Cochrane review first published in 2007.
OBJECTIVES: To examine the effects of exercise interventions on balance in older people, aged 60 and over, living in the community or in institutional care.
SEARCH STRATEGY: We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register, CENTRAL (The Cochrane Library 2011, Issue 1), MEDLINE and EMBASE (to February 2011).
SELECTION CRITERIA: Randomised controlled studies testing the effects of exercise interventions on balance in older people. The primary outcomes of the review were clinical measures of balance.
DATA COLLECTION AND ANALYSIS: Pairs of review authors independently assessed risk of bias and extracted data from studies. Data were pooled where appropriate.
MAIN RESULTS: This update included 94 studies (62 new) with 9,917 participants. Most participants were women living in their own home. Most trials were judged at unclear risk of selection bias, generally reflecting inadequate reporting of the randomisation methods, but at high risk of performance bias relating to lack of participant blinding, which is largely unavoidable for these trials. Most studies only reported outcome up to the end of the exercise programme. There were eight categories of exercise programmes. These are listed below together with primary measures of balance for which there was some evidence of a statistically significant effect at the end of the exercise programme. Some trials tested more than one type of exercise. Crucially, the evidence for each outcome was generally from only a few of the trials for each exercise category.
1. Gait, balance, co-ordination and functional tasks (19 studies of which 10 provided primary outcome data): Timed Up & Go test (mean difference (MD) -0.82 s; 95% CI -1.56 to -0.08 s, 114 participants, 4 studies); walking speed (standardised mean difference (SMD) 0.43; 95% CI 0.11 to 0.75, 156 participants, 4 studies), and the Berg Balance Scale (MD 3.48 points; 95% CI 2.01 to 4.95 points, 145 participants, 4 studies).
2. Strengthening exercise (including resistance or power training) (21 studies of which 11 provided primary outcome data): Timed Up & Go Test (MD -4.30 s; 95% CI -7.60 to -1.00 s, 71 participants, 3 studies); standing on one leg for as long as possible with eyes closed (MD 1.64 s; 95% CI 0.97 to 2.31 s, 120 participants, 3 studies); and walking speed (SMD 0.25; 95% CI 0.05 to 0.46, 375 participants, 8 studies).
3. 3D (3 dimensional) exercise (including Tai Chi, qi gong, dance, yoga) (15 studies of which seven provided primary outcome data): Timed Up & Go Test (MD -1.30 s; 95% CI -2.40 to -0.20 s, 44 participants, 1 study); standing on one leg for as long as possible with eyes open (MD 9.60 s; 95% CI 6.64 to 12.56 s, 47 participants, 1 study), and with eyes closed (MD 2.21 s; 95% CI 0.69 to 3.73 s, 48 participants, 1 study); and the Berg Balance Scale (MD 1.06 points; 95% CI 0.37 to 1.76 points, 150 participants, 2 studies).
4. General physical activity (walking) (seven studies of which five provided primary outcome data).
5. General physical activity (cycling) (one study which provided data for walking speed). 6. Computerised balance training using visual feedback (two studies, neither of which provided primary outcome data).
7. Vibration platform used as intervention (three studies of which one provided primary outcome data).
8. Multiple exercise types (combinations of the above) (43 studies of which 29 provided data for one or more primary outcomes): Timed Up & Go Test (MD -1.63 s; 95% CI -2.28 to -0.98 s, 635 participants, 12 studies); standing on one leg for as long as possible with eyes open (MD 5.03 s; 95% CI 1.19 to 8.87 s, 545 participants, 9 studies), and with eyes closed ((MD 1.60 s; 95% CI -0.01 to 3.20 s, 176 participants, 2 studies); walking speed (SMD 0.04; 95% CI -0.10 to 0.17, 818 participants, 15 studies); and the Berg Balance Scale ((MD 1.84 points; 95% CI 0.71 to 2.97 points, 80 participants, 2 studies).

Few adverse events were reported but most studies did not monitor or report adverse events. In general, the more effective programmes ran three times a week for three months and involved dynamic exercise in standing.
AUTHORS' CONCLUSIONS: There is weak evidence that some types of exercise (gait, balance, co-ordination and functional tasks; strengthening exercise; 3D exercise and multiple exercise types) are moderately effective, immediately post intervention, in improving clinical balance outcomes in older people. Such interventions are probably safe. There is either no or insufficient evidence to draw any conclusions for general physical activity (walking or cycling) and exercise involving computerised balance programmes or vibration plates. Further high methodological quality research using core outcome measures and adequate surveillance is required.