To compare the effectiveness of concentrically-focused resistance training (CNCRT) to eccentrically-focused resistance training (ECCRT) on physical function and functional pain in knee osteoarthritis (OA).
Randomized, single-blinded controlled four-month trial. Older adults with knee OA (N=88; 68.3±6.4 yr, 30.4±6.9 kg/m and 67.4% women) were randomized to ECCRT, CNCRT or no-exercise control (CON). Main outcomes included chair rise time, stair climb time, six-minute walk test distance, temporalspatial parameters of gait, community ambulation and functional pain.
Leg muscle strength improved in both training groups compared to CON. There were no significant group x time interactions for any functional performance score (chair rise time, stair climb time, six-minute walk test distance, gait parameters, community ambulation). Compared to CON, functional pain scores were reduced for chair rise (-38.6% CNCRT, -50.3% ECCRT vs +10.0%) and stair climb (-51.6% CNCRT, -41.3% ECCRT vs +80.7%; all p<0.05). Pain scores were reduced during the six-minute walk and in early recovery with CNCRT compared to the remaining two groups (p<0.05).
Either resistance exercise type improves activity-related knee OA pain, but CNCRT more effectively reduced severity of ambulatory pain and pain upon walking cessation.