Stay the Course. Image accompanying iRunFar’s report; reduced and presented for news commentary with the attributed report. View the complete source report.
Runners often attribute stiffness to aging or running technique, but joint instability can be a hidden cause. Excessive stiffness and pain may stem from unstable joints, leading to chronic issues.
Joint instability occurs when excessive movement happens between bones, disrupting the stability tripod. This can lead to chronic pain, weakness, and reduced running performance. Older runners, especially those over 40, often experience this. Read more everyday miles coverage.
Signs of joint instability include excessive mobility, rapid loss of mobility gains, and immediate improvements from stabilization exercises. Addressing instability through targeted exercises can improve strength, mobility, and running performance. Related: Runner Misdiagnoses Chronic Fatigue as Normal Training Fatigue.
This original Runner World brief is based on reporting from iRunFar. Visit the source for its complete reporting, context and any later corrections.
Reader questions
Questions about this report
What should runners know about Joint Instability: The Overlooked Cause of Runner Stiffness?
Joint instability, not aging, may be causing your chronic stiffness and pain. Runners often attribute stiffness to aging or running technique, but joint instability can be a hidden cause. Excessive stiffness and pain may stem from unstable joints, leading to chronic issues.
When did Runner World publish this everyday miles brief?
Runner World published this brief on August 18, 2026. The underlying iRunFar report was dated August 18, 2026.
Where can readers find the complete original report?
This summary is based on reporting from iRunFar. The attributed source link in the article leads to the publisher’s complete report.
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