Assessment of Efficacy of Low Intensity Resistance Training in Men at Risk for Symptomatic Knee Osteoarthritis

The purpose of this research study is to determine whether low intensity resistance training with concurrent application of a peripheral blood flow restriction device to the exercising limb will elicit increased quadriceps strength, functional gains, ability to complete knee-related activities of daily living, mobility, and quality of life in individuals at risk for developing symptomatic knee osteoarthritis (OA). It is known that higher quadriceps strength is protective against developing symptomatic knee OA.1 However, people at risk for knee OA frequently do not tolerate the high intensity resistance training that is generally believed necessary to increase muscle strength. Partial blood flow restriction (PBFR) to the exercising muscle has been reported to result in strength gains, while requiring lower levels of joint loading.2 This method may be better tolerated, enabling efficacious exercise in older adults who may not tolerate high knee joint loads. To asses the efficacy of a 4 week low-intensity resistance training program with concurrent application of PBFR to the exercising limbs to improve quadriceps strength and size, leg muscle power, and mobility in individuals at risk for developing symptomatic knee osteoarthritis,we will test the following hypotheses. In comparison with low-intensity resistance training without use of PBFR, a four-week low-intensity resistance-training program with PBFR will: Primary Hypothesis: Increase (a) double leg-press 1RM strength and (b) isokinetic knee extensor strength Secondary Hypotheses: 1. Increase quadriceps muscle volume assessed by MRI 2. Increase lower limb muscle power on (a) double leg-press at 40% 1RM and (b) a timed stair climb 3. Not adversely effect knee pain or quality of life assessed by the Knee injury and Osteoarthritis Outcome Score (KOOS) questionnaire