It all started a few years ago when Baldwin was hosting SNL and Davidson was appearing in a skit in which he was shirtless.
"I guess I'm a little bit cut or whatever," Davidson said. "There's no, like, nice way to say that."
Baldwin then asked Davidson how he stays lean. "I didn't want to be rude and say like, 'I still have metabolism,'" The King of Staten Island star recalled. "'I'm not in my mid-50s. I just wake up like this.'"
So, Davidson told Baldwin he does 100 push-ups and 100 sit-ups every day.
Later on, Baldwin was cast as former President Donald Trump on the show. As a result, Davidson started seeing him around the set more often.
"Every time we would run into the hall, he'd be like, '100 a day'" Davidson said. "And he started to do it and he lost, like, 100 pounds. And he says it's all because of me."
"I started juicing in the morning—I don't eat breakfast," the 30 Rock alum, who also said he does intermittent fasting, shared. "I wanted to lose weight because I was pre-diabetic, and I didn't want to shoot insulin. So, I started juicing—green juices, cashew milk—and just trying to eliminate sugar as much as possible."
Watch the interview to hear Davidson tell the whole story.
(E! and NBC are both part of the NBCUniversal family).