Six studies (number of participants not reported) were included in the review. No details of study designs were reported. PEDro scores ranged from one to six.
Postural control measures: Four studies reported eight different outcomes. Only two outcomes were reported by more than one study. Effect sizes varied substantially across outcome measures and ranged from small to large (0.38 to 1.18). Three assessments from two studies (two used Biodex balance system and one used mediolateral time to stabilisation) showed no significant effect for functional training; one study that used Star Exercise Balance Test showed a negative effect.
Self-reported outcomes: Three studies provided five data sets for effect sizes based on self-reported outcome measures. Two studies reported significant improvements in ankle function using the FADI and FADI-sport score (one study) and Ankle Joint and Foot Assessment Tool (AJFAT); effect sizes were high (0.77 to 2.66). The third study also used the FADI and FADI-sport score and showed no significant effect for functional training. It should be noted that the text of the results section suggested that all three studies reported significant effects.
Risk of sprain subsequent to functional training: One study reported a reduction in risk for proprioceptive training compared with control (RR 0.13, 95% CI 0.003 to 0.93), but no significant effect for strength training. A second study did not include a control group, but compared an ankle brace group with proprioceptive- and technical landing-training groups; the authors used the brace group as a control and calculated relative risks of 0.31 for technical training and 0.18 for proprioceptive training.