3 doctors weighed in:
Why do my legs give out after running for extended periods?
3 doctors weighed in

Dr. Amir Khan
Sports Medicine
2 doctors agree
In brief: Fatigue?
Common reasons for giving out include 1) instability from ligament insufficiency or tear, 2) weak muscle from atrophy/weakness/muscle disease etc.
3) pain. After extended running its possible you are experiencing fatigue which prevents your muscles from properly firing and holding you up. Therefore you must be properly hydrated, conditioned and trained to undergo rigorous running.

In brief: Fatigue?
Common reasons for giving out include 1) instability from ligament insufficiency or tear, 2) weak muscle from atrophy/weakness/muscle disease etc.
3) pain. After extended running its possible you are experiencing fatigue which prevents your muscles from properly firing and holding you up. Therefore you must be properly hydrated, conditioned and trained to undergo rigorous running.
Dr. Amir Khan
Dr. Amir Khan
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