By Ken Berger

Here’s a summary of several studies linking leg strength, leg power, walking ability, joint health, and fall risk in older adults.

A classic analysis of older, mostly sedentary adults looked at how leg strength and walking speed changed over nine months. The researchers found that changes in leg strength were closely tied to changes in gait speed: people who improved their leg strength tended to walk faster, regardless of how strong they were at the beginning.

https://academic.oup.com/biomedgerontology/article/58/12/M1125/591645

Another study examined whether changes in leg power explained meaningful improvements in mobility. Participants completed a leg‑press power program, and improvements in leg power were strongly associated with clinically important gains in walking speed and other mobility measures. The takeaway: increasing leg power (how quickly you can produce force) is a key driver of better real‑world movement.

https://pmc.ncbi.nlm.nih.gov/articles/PMC3051803/

Research has also linked lower‑limb strength and power with fall history. A 2025 analysis reported that weaker lower‑limb strength was associated with a higher likelihood of recurrent or injurious falls in older adults. Other work using sit‑to‑stand and leg extension power tests has shown that lower values predict a higher risk of future falls.

https://pubmed.ncbi.nlm.nih.gov/39915768/
https://www.nature.com/articles/s41598-023-50574-7
https://www.nature.com/articles/s41598-020-73395-4
https://pubmed.ncbi.nlm.nih.gov/15209650/

Several papers focus on quadriceps strength and knee health. One study found that weaker quadriceps were associated with worse self‑reported function and more disability in people with knee osteoarthritis. Other work suggests that better quadriceps strength may help protect certain compartments of the knee from cartilage loss, particularly when alignment is normal. More recent analyses show a relationship between frequent knee pain and long‑term quadriceps weakness, even when radiographic progression is modest.

https://pmc.ncbi.nlm.nih.gov/articles/PMC4060309/

https://pubmed.ncbi.nlm.nih.gov/12693882/
https://mayoclinic.elsevierpure.com/en/publications/quadriceps-strength-and-the-risk-of-cartilage-loss-and-symptom-pr
https://acrjournals.onlinelibrary.wiley.com/doi/10.1002/acr2.70067
https://www.rheumatologyadvisor.com/news/knee-pain-linked-to-quadriceps-weakness-over-time/

Finally, narrative and observational reviews on mobility in community‑dwelling older adults highlight leg strength and power as central to maintaining walking ability, negotiating stairs, and participating in daily life roles.

https://pmc.ncbi.nlm.nih.gov/articles/PMC5007738/

https://www.frontiersin.org/articles/10.3389/fphys.2020.00881/full

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0300818

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