High-intensity versus low-intensity resistance training in patients with knee osteoarthritis: A randomized controlled trial.

Objectives: To assess whether (i) high-intensity resistance training (RT) leads to increased muscle strength compared to low-intensity RT in patients with knee osteoarthritis (OA); and (ii) RT with vitamin D supplementation leads to increased muscle strength compared to placebo in a subgroup with vitamin D deficiency.

Design: Randomized controlled trial.

Setting: Outpatient rehabilitation centre.