https://marathonhandbook.com/why-legs-feel-heavy-when-running/
7 common causes of heavy legs when running and how to fix them.
1. Poor Running Form
2. Excessive Weight Training
3. Overtraining
4. Not Enough Carbs and Iron
5. Dehydration
6. Sleep Deprivation
7. Poor Blood Circulation
I’ll take a dozen Domican’s playing ball with broomsticks and cardboard gloves… living in huts with dirt floors, no plumbing and drinking goat milk.
They’ll out run and out hustle all the 18 year olds paying attention to everything you just listed