# Exercise as Osteoarthritis Treatment in Wistar Rats Promotes Frequency-Dependent Benefits

## TL;DR

This study shows that exercising five times a week provides greater benefits than three times a week in treating osteoarthritis in rats.

## Contribution

The study demonstrates that higher exercise frequency leads to better therapeutic outcomes in osteoarthritis.

## Key findings

- Exercising five times a week reduced inflammation and improved cartilage protection more than three times a week.
- Higher frequency exercise resulted in greater weight reduction and energy expenditure in rats with osteoarthritis.
- Both exercise regimens inhibited osteoarthritis progression, but five times a week showed more pronounced effects.

## Abstract

Osteoarthritis is a disease that causes joint pain and difficulty moving, affecting millions of people worldwide. This study investigated how different frequencies of moderate treadmill exercise could aid in the treatment of osteoarthritis in rats. The treatment consisted of exercising three or five times per week. The results showed that both exercise regimens helped inhibit the progression of the disease, but exercising five times per week provided more significant benefits, such as higher energy expenditure, weight reduction, decreased inflammation, and better cartilage protection. This suggests that exercise frequency is important for optimizing outcomes. These findings indicate that regular exercise, especially at higher frequencies, may be an effective and accessible strategy for managing osteoarthritis, improving patients’ quality of life.

This study investigated the effects of different frequencies of moderate treadmill exercise on a knee osteoarthritis (OA) model in Wistar rats. Sixty male Wistar rats were randomly assigned to four groups: Sham, OA, OA + exercise three times/week (OA + 3×), and OA + exercise five times/week (OA + 5×). OA was induced via intra-articular injection of sodium monoiodoacetate (MIA) in the right knee. Fifteen days post-MIA, exercise treatment began with a one-week adaptation period, followed by eight weeks of aerobic training. Protocols involved treadmill walking (30 min/day) at 13 m/min for the first four weeks and 16 m/min for the last four weeks. At the end, animals were anesthetized and euthanized for collection of intra-articular tissues and gastrocnemius muscle. Both exercise regimens inhibited OA progression; however, OA + 5× yielded more pronounced effects, including greater energy expenditure, weight reduction, oxidative stress modulation, decreased pro-inflammatory and catabolic markers, increased anti-inflammatory and anabolic parameters, reduced injury scores, prevention of cartilage thinning, and increased cartilage surface area. Although both frequencies conferred cartilage protection, moderate exercise five times per week produced superior therapeutic outcomes, suggesting a dose-dependent benefit of exercise in OA management.