Osteoarthritis

Background

Osteoarthritis (OA) is a leading cause of disability in older adults.The knee is the most common weight-bearing joint affected by OA, with an estimated 45% of all adults at risk of developing symptomatic knee OA in their lifetime. One biomechanical factor that may significantly contribute to incident symptomatic knee OA and progression of cartilage loss is quadriceps weakness.3–5 Multiple studies have reported that individuals with knee OA have weak quadriceps muscles,4,6–11 and an observational study revealed that higher quadriceps strength protected against the development of incident symptomatic knee OA.5 Since the quadriceps, in addition to other lower limb muscles, are necessary for knee loading and stability during locomotion, increasing quadriceps muscle strength may result in increased physical function of those with or at risk of knee OA and decrease the incidence and/or progression of the disease.

Greater quadriceps strength has been associated with lower risk of symptomatic knee osteoarthritis (OA) in older adults. However, factors that confer elevated risk of knee OA (eg, sedentary lifestyle, obesity, and knee injury) also contribute to a reduced tolerance of resistance training programs at ≥60% 1-repetition maximum (1RM). Therefore, the current study assessed whether concurrent application of blood flow restriction (BFR) to low-load resistance training is an efficacious and tolerable means of improving