Trajectories of perceived exertion and pain over a 12-week neuromuscular exercise program in patients with knee osteoarthritis

Osteoarthritis Cartilage. 2020 Nov;28(11):1427-1431. doi: 10.1016/j.joca.2020.07.011. Epub 2020 Aug 21.


Background: Exercise programs rely on the overload principle, yet patients with knee osteoarthritis (OA) may not adequately progress exercises due to fear of exacerbating symptoms.

Objective: To describe trajectories for perceived exertion and exercise-induced knee pain during a neuromuscular exercise program for patients with knee OA.

Design: Participants with knee OA completed a 12-week neuromuscular exercise program consisting of weekly supervised sessions plus home exercises. During each supervised session, the Borg's rating of perceived exertion (RPE; 6 = no exertion, 20 = maximal exertion) and knee pain (pre, post, max) using Numeric Rating Scales (NRS; 0 = no pain, 10 = worst imaginable pain) were completed. Mean changes in RPE and pain from weeks 1-12 were calculated. Mixed effects regression was used to investigate trajectories over time (weeks) for RPE, and maximum pain (pre-to-max) and pain-change (pre-to-post) during exercise.

Results: 56 patients (95%) completed the program. From week 1-12, RPE increased by 2.6 (95%CI, 1.7 to 3.5), from 'somewhat hard' to 'very hard', while max pain decreased by 1.0 NRS (95%CI, 0.5 to 1.3) and pain-change decreased by 0.9 NRS (95%CI, 0.4 to 1.3). Linear mixed effects regression showed a quadratic increase for RPE over time until between weeks 9 and 10, then RPE plateaued. Maximum pain decreased linearly over time. Pain-change showed a quadratic decrease over time until approximately week 9, then pain-change plateaued.

Conclusions: In patients with knee OA participating in a 12-week neuromuscular exercise program, perceived exertion during exercise progressed from 'somewhat hard' to 'very hard' at 9 weeks, while exercise-induced knee pain decreased. Patients were able to work harder while experiencing decreases rather than increases in pain.

Keywords: Knee osteoarthritis; Neuromuscular exercise; Pain; Perceived exertion; RPE.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arthralgia / physiopathology*
  • Exercise Therapy / methods*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Osteoarthritis, Knee / physiopathology
  • Osteoarthritis, Knee / rehabilitation*
  • Physical Exertion*

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