Exercise has been strongly promoted for the prevention of the major diseases of aging in women, such as cardiovascular disease and osteoporosis. However, conflicting data exist as to whether exercise benefits joint health and thus helps protect against degenerative processes such as knee osteoarthritis. The aim of this study was to examine the cross-sectional relationship between exercise and knee joint cartilage in women at midlife.
A total of 176 women aged 40 to 67 years with no clinical knee osteoarthritis or history of significant knee injury were recruited from the community and had magnetic resonance imaging performed on their dominant knee to assess tibial cartilage volume and defects. The women completed a questionnaire to determine fortnightly exercise participation and frequency.
Fortnightly participation in exercise at an intensity that caused tachypnea and an increased pulse rate for at least 20 minutes was positively associated with the volume of the medial tibial cartilage (P = 0.02). There was a tendency for the frequency of exercise at this intensity to be positively associated with medial tibial cartilage volume (P = 0.07). Exercise participation was not significantly associated with the presence of knee cartilage defects.
Participation in exercise that causes tachypnea and an increased pulse rate for at least 20 minutes was associated with greater medial tibial cartilage volume, but not knee cartilage defects in non-healthcare-seeking women at midlife. More frequent exercise also tended to be associated with greater medial tibial cartilage volume. Although our findings need to be confirmed longitudinally, they provide further support for a beneficial effect of regular exercise on diseases related to aging.
Magnetic resonance imaging was performed to assess tibial cartilage volume and defects, and a questionnaire was used to determine fortnightly exercise participation and frequency. The results demonstrated that both participation and frequency of exercise in women are positively associated with knee cartilage volume, without being associated with the risk for cartilage defects.
From the 1National Health and Medical Research Council of Australia Centre of Clinical Research Excellence for the Study of Women's Health, Monash University Medical School, Alfred Hospital, Prahran, Victoria, Australia; 2Department of Epidemiology and Preventive Medicine, Monash University Medical School, Alfred Hospital, Prahran, Victoria, Australia; 3The Jean Hailes Foundation, Clayton, Victoria, Australia; and 4MRI Unit, Mayne Health Diagnostic Imaging Group, Epworth Hospital, Richmond, Victoria, Australia.
Received October 10, 2006; revised and accepted November 16, 2006.
Funding/support: This work was supported by grants 219279 and 334267 from the National Health and Medical Research Council of Australia.
Financial disclosure: None reported.
Address correspondence to: Flavia Cicuttini, MBBS, PhD, Department of Epidemiology and Preventive Medicine, Monash University, Central and Eastern Clinical School, Alfred Hospital, Melbourne, Victoria 3004, Australia. E-mail: email@example.com.