The importance of dose in land-based supervised exercise for people with hip osteoarthritis. A systematic review and meta-analysis.

PURPOSE: To compare effects of land-based exercise programmes with high vs low or uncertain compliance with dose recommendations among people with hip osteoarthritis (OA).

DESIGN: A systematic review with meta-analyses of supervised exercise programmes in people with symptomatic hip OA was conducted. Dose of the exercise interventions was evaluated according to the American College of Sports Medicine's (ACSM) recommendations for developing and maintaining cardiorespiratory fitness, muscular strength and flexibility in healthy adults. Compliance ratios with the recommendations were calculated. Standardized Mean Differences (SMDs) were calculated in meta-analyses for the outcomes pain and self-reported physical function. Outcome effects were compared between the sub-groups of studies with interventions with "high" vs "uncertain" compliance with the ACSM recommendations.

RESULTS: Twelve studies including 1202 participants were included. Seven were categorized with "high" and five with "uncertain" compliance with the ACSM recommendations. Ten studies had an overall low risk of bias. Comparing exercise with no exercise, the pooled SMD for pain was -0.42 (95% CI -0.58, -0.26) in the high compliance group, favouring exercise. In the uncertain compliance group the pooled SMD was 0.04 (95% CI -0.24, 0.31). For physical function the SMD was -0.41 (95% CI -0.58, -0.24) in the high compliance group and -0.23 (95% CI -0.52, 0.06) in the uncertain compliance group.

CONCLUSIONS: The results show that land-based supervised exercise interventions with high compliance to the ACSM recommendations result in significantly larger improvements in pain and non-significantly larger improvement in self-reported physical function compared with land-based supervised exercise interventions with uncertain compliance.