Intensity of challenge to the balance system is not reported in the prescription of balance exercises in randomised trials: a systematic review

Question: How has balance challenge intensity been reported in trials of balance exercise interventions? Are there any instruments designed to measure the intensity of balance challenge in balance training exercises? Design: Systematic review of randomised trials of balance training exercises. Participants: Older adults, ie, the majority of subjects were aged over 55 years. Intervention: Balance exercise intervention, or multi-dimensional intervention that included a balance exercise intervention. Outcome measures: The included trials were examined for descriptions and instruments used to report the intensity of the challenge to the patient's balance system provided by the balance exercise prescribed. The other included studies were examined for instruments that measure balance challenge intensity. Results: In most of the 148 randomised trials identified, measures of reported balance challenge 'intensity' were actually measures of some other aspect of the exercise, eg, aerobic intensity or a hierarchy of task difficulty without reference to the patient's ability. Three potential systems of measuring the balance challenge intensity were identified. Two were not described in any detail. One was defined in terms of the limits of the patient's postural stability, but this system appears not to have been validated. No adequate measures of balance challenge intensity were found among the other types of studies identified. Conclusion: The review highlights a serious gap in the methods used to prescribe, implement, and evaluate the effect of balance exercise programs. Comprehensive work in this area is required to develop a psychometrically sound measure of balance exercise intensity.