In a review of more than 200 clinical trials, scientists have identified which exercise offers the most benefits in relieving the symptoms of knee osteoarthritis in both the short and long term. It’s the most comprehensive look at physical activity in treating the condition yet.
In an international study led by researchers from Zhejiang University in China, the data of 15,684 people with knee osteoarthritis was pooled to compare six major exercise types, which included activities like walking and cycling, and tracked how their effects changed over time. The scientists focused on whether any one type of workout could improve pain, function, gait performance and quality of life.
To best represent the data from so many studies, the team slotted exercises into categories: aerobic (brisk walking, cycling, aquatic aerobics, treadmill work, stair climbing); strengthening (resistance training targeting quadriceps and hamstrings, typically with bands, weights, or body-weight squats, leg presses); flexibility (stretching and range-of-motion routines); neuromotor (balance, coordination and agility training); mind-body (tai chi, yoga, qigong, Pilates); and mixed (a combination of the others). For mixed exercises, 88% included strengthening, most often paired with neuromotor, flexibility or aerobic components.
The results were then divided into three follow-up periods: four weeks (short-term), 12 weeks (mid-term) and 24 weeks (long-term) after participants began exercising, substituting the closest data when exact time frames weren’t available. And this structure revealed how different types of exercise shine at different stages of recovery.
What they found was that by 12 weeks, aerobic exercise such as brisk walking, cycling or pool workouts produced the biggest improvements in function, roughly doubling the benefit seen with resistance training. They also offered the most relief, cutting reported pain scores by more than a full standard deviation compared with control groups – a large effect by medical standards. And aerobic exercise had about a 70% probability of being the best overall intervention across all measured outcomes.
Aerobic exercise performed strongly across all follow-up periods, relieving short- and mid-term pain, improving short-, mid- and long-term function, and improving short- and mid-term gait performance and quality of life.
“Patients should engage regularly in structured aerobic activities, such as walking, cycling, or swimming, to optimize symptom management,” the researchers noted. “If aerobic exercise is not possible owing to individual limitations, alternative forms of structured physical activity may still be beneficial. Patients should consult healthcare professionals to develop an individualized exercise plan that aligns with their physical capabilities and treatment goals.”
Mixed programs also performed well, especially those that combined strength with balance or stretching exercises. These routines – typically involving leg presses, banded knee extensions, sit-to-stands and glute work two or three times a week – delivered moderate, clinically meaningful improvements in mobility and daily function at 12 weeks. However, they didn’t ease pain as effectively as aerobic exercise, which remained the clear leader for symptom relief.
Meanwhile, mind-body exercise appeared to boost short-term function, neuromotor activities probably resulted in a large increase in short-term gait performance, and strengthening and mixed exercise seemed to improve function the most at the mid-term mark. It’s worth noting that there were no more adverse safety events in the exercise cohort overall, compared with the control group.
And even though none of these exercises are harmful, neuromotor training on its own appeared to be the least helpful for managing knee OA symptoms, especially pain relief. The research suggests that it’s valuable only as an add-on to build stability and confidence once pain is under control and strength has been built.
Osteoarthritis (OA) affects around 528 million people worldwide, including 23% of people aged 40 years and over, and is the result of progressive damage to articular cartilage, which causes pain, stiffness and reduced mobility. And while any joint can develop this, it’s most common in the knees – almost 30% of individuals over 45 show signs of OA in this joint, with half of those people having severe issues because of it.
Right now, there are no clear guidelines on which exercise is best – just that physical activity is important and considered a frontline treatment. The researchers hope this study will help address that. In June, another team of researchers looked at non-drug treatments for knee OA, noting that there’s a lot of information and, again, much debate as to what’s best over time – and what isn’t.
Here, it was clear that the best exercise is one that moves the legs rhythmically and raises the heart rate, ideally on most days of the week. Adding targeted strength and balance training improves control and stability, and including stretching or something like yoga or tai chi can help maintain comfort and consistency in the long-term. However, aerobic exercise should form the foundation, with the other activities sprinkled into a routine.
While the researchers noted the study’s limitations – indirect comparisons between exercise types, some trials lacking long-term data, and how small studies may have influenced the short-term effects data – the findings offer a comprehensive guide for patients and clinicians as they look for the best ways of managing the condition. The researchers also noted that in their efforts to pool all existing data, they found there was a serious lack of larger and long-term trials – which seems remiss considering knee OA is a chronic and progressive condition.
“Only a few studies (n=12, 5.5%) have reported follow-up data beyond one year,” they wrote. “Therefore, future research should prioritize well designed, adequately powered trials with longer follow-up durations to better assess the durability of exercise effects over time. Finally, Kellgre-Lawrence grading was recorded to classify the severity of knee osteoarthritis in the included studies. However, nearly all studies included participants with different Kellgre-Lawrence grades, making it difficult to distinguish the therapeutic effects of exercise intervention on patients with different degrees of knee osteoarthritis. Future research focusing on disease severity could help clinicians make more informed choices regarding exercise therapy for patients with knee osteoarthritis.”
Of course, while the data makes a strong case for aerobic exercise, as always, consult your medical professional before undertaking any new workout plans.
“Exercise treatment offers obvious benefits for individuals with knee osteoarthritis,” the researchers concluded. “With moderate certainty quality evidence, aerobic exercise might be the best exercise modality for improvements in pain, function, gait performance, and quality of life. This study presents a comprehensive and up-to-date analysis of the effects of exercise intervention as a treatment strategy for knee osteoarthritis, which could assist clinicians in prescribing therapy to improve treatment outcomes for patients.”
The study was published in the journal The BMJ.
Source: The BMJ Group via Scimex
