Eccentric and Concentric Resistance Exercise Comparison for Knee Osteoarthritis

Area of Science:

• Orthopedics
• Sports Medicine
• Rehabilitation

Background:

• Knee osteoarthritis (OA) is a prevalent condition causing pain and functional limitations.
• Resistance exercise is a common intervention for managing knee OA symptoms.
• Different modes of resistance exercise, such as eccentric and concentric contractions, may have varying effects.

Purpose of the Study:

• To compare the efficacy of eccentrically focused resistance exercise (ECC RT) versus concentrically focused resistance exercise (CNC RT) in improving knee OA symptoms and strength.
• To evaluate the impact of different resistance training types on muscle strength and patient-reported outcomes in individuals with knee OA.

Main Methods:

• A randomized controlled trial involving 90 participants with knee OA.
• Participants were assigned to either ECC RT, CNC RT, or a no-exercise control group for four months.
• Outcomes included one-repetition maximal strength, rate of strength gain, and Western Ontario and McMaster University Osteoarthritis Index (WOMAC) scores.

Main Results:

• Both ECC RT and CNC RT groups demonstrated significant improvements in leg strength (16%-28%) compared to the control group.
• The rate of weekly strength gain was higher in the CNC RT group for leg press and knee flexion.
• No significant differences in WOMAC scores were observed between the exercise groups, although strength changes predicted symptom improvements.

Conclusions:

• Both eccentric and concentric resistance training effectively enhance leg strength in individuals with knee OA.
• Muscle strength gains, regardless of contraction type, can positively influence knee OA function and pain.
• Individual preference, goals, and tolerance may guide the choice between ECC RT and CNC RT.