4 hours a day of stair running? That's completely bonkers. I used to stair run for 20 minutes ... and it kicked my butt in my 20s. FWIIW, buy a kettlebell and

4 hours a day of stair running? That's completely bonkers. I used to stair run for 20 minutes ... and it kicked my butt in my 20s. FWIIW, buy a kettlebell and take glycine/eat bone soup.