American personal trainer and entrepreneur who’s best acknowledged for having co-founded the Intense Performance Training curriculum. He’s also known for having completed the Angeles Crest 100-mile stamina run. He began monitoring altitude and hypoxic trained in 2006. He released a book entitled Power Speed Stamina. He is wedded to 2x Rowing Olympic Platinum Medalist Erin Cafaro MacKenzie. In March 2017 he published an image with fellow personal trainer Emily Bridgers to his iamunscared Instagram accounts.