Association between knee extensor strength and pulmonary function in the female elderly.
Jaeseok Lee, Dongwook Han
PMID 29545684WHAT IT FOUND
Knee extensor strength correlates with lung capacity in older women, explaining about a third of the variance in vital capacity.
Stronger legs are associated with better breathing, but the cross-sectional design cannot prove that leg exercises improve lung function.
Key findings
01Knee extensor strength showed significant positive correlations with forced vital capacity, FEV1, peak expiratory flow, and FEF25-75%.
02Knee extensor strength explained 32% of the variance in forced vital capacity and 30% of the variance in FEV1.
03The authors concluded that weakening knee extensor muscles restricts physical activity, which serves as a key factor in decreasing lung capacity.
STILL TO COME
How it was doneWhat they foundWhat it means for PTsWhat it means for OTs
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
Cross-sectional design cannot establish causation; it is unknown whether weak legs cause poor lung function or if both are consequences of aging and inactivity. Small sample size of 33 participants limits generalizability. Only healthy, non-smoking women were included, so findings do not apply to men, smokers, or those with existing lung disease. The study excluded individuals with leg pain or lung disease, potentially selecting a healthier subset than typical clinical populations.
Declared interests
No funding sources or conflicts of interest were declared in the provided text.
The easy way to misread this
Do not assume that prescribing knee extensor exercises will directly improve pulmonary function. This study is correlational and shows an association, not that strengthening legs causes better breathing.