A new research study by University of California, San Francisco (UCSF) has shown that over-exercising middle-aged people may develop arthritis.
The research has shown that middle-aged men and women who engage in high levels of physical activity may be unknowingly causing damage to their knees.
"Our data suggests that people with higher physical activity levels may be at greater risk for developing knee abnormalities and thus, at higher risk for developing osteoarthritis," said Dr Christoph Stehling, research fellow in the Department of Radiology and Biomedical Imaging at the University of California, San Francisco (UCSF) and radiology resident in the Department of Clinical Radiology, University of Muenster, Germany.
The study involving 236 asymptomatic participants aged 45 to 55, has shown that running and jumping are bad for people in middle age, while swimming and cycling are much better as they do not put so much pressure on bones and joints.
"The prevalence of the knee abnormalities increased with the level of physical activity. In addition, cartilage defects diagnosed in active people were more severe," said Stehling.
"This study and previous studies by our group suggest that high-impact, weight-bearing physical activity, such as running and jumping, may be worse for cartilage health.
"Conversely, low-impact activities, such as swimming and cycling, may protect diseased cartilage and prevent healthy cartilage from developing disease," Stehling added.
Specific knee abnormalities identified included meniscal lesions, cartilage lesions, bone marrow edema, and ligament lesions.
The study was presented at the annual meeting of the Radiological Society of North America (RSNA).