I am a 51 year young man. I started the program about 1.5 years ago. I wanted a real fitness program to follow and ATHLEAN-X looked great to me. I was impressed that Jeff was a physical therapist on top of being a conditioning coach. I used trainers before and hurt myself using their methods. I later realized they knew nothing about how the body functioned. There are too many knuckleheads giving bad advice! I will be running the Worlds Tougest Mudder with my step son and nephew in November. Thanks to Jeff, I feel more than capable of completing the 24 hour challenge. Thank you for the program and the education provided along the way.