There’s been a lot of chatter recently about how shredded Michael Phelps looks as he prepares for what he says will be his final Olympics this summer in Rio de Janeiro. His work ethic and training methods have been put on full display in an amazing new commercial by Under Armour, Phelps’s brand partner since 2010.

Under the tagline “It’s what you do in the dark that puts you in the light,” the ad is a montage of some of the work Phelps puts in behind the scenes, from Deadlifts to swimming with a parachute for resistance to recovering in a cold tub.

The most impressive exercise shown in the 90-second spot is the Hanging Single-Leg Raise, which Phelps performs several times. This exercise has immense benefits, but it’s excruciating to do.

Phelps says a major key to his newfound fitness has been the elimination of alcohol from his diet. Phelps, who has dealt with alcohol issues in the past, says he hasn’t had a drink in over a year and a half.

“It’s incredible. It’s not only my body—on a lot of different levels,” Phelps said. “It’s been amazing. I can really tell the difference with my body, sort of not carrying that weight on my back.”

The Summer Olympics in Rio kick off on Aug. 5.