Even during spring break.
Green showed up for spring football in late February at 227 pounds, a vast improvement from his check-in weight at 2013 preseason camp -- approximately 240 pounds -- but still heavier than he wanted to be. Michigan went through two limited-contact practices before players embarked on spring break the first week of March.
College students do a lot of things on spring break. Losing weight, at least voluntarily, isn't one of them. But Green went home to Virginia and shed seven pounds before returning to Michigan for practice this week.
"I have a personal trainer at home, so I was working out twice a day," Green told ESPN.com on Tuesday. "Obviously [I was] on a strict diet and watching what I ate. I feel great at this weight, better than I ever felt before."
It's a good sign for Green, who headlined Michigan's decorated 2013 recruiting class but never fully got on track last season. He showed up significantly overweight and then suffered an ankle injury in camp that slowed his development. Green, who ranked as the nation's No. 5 running back in the 2013 class, recorded 270 yards and two touchdowns on 83 carries for the Wolverines.
Michigan's run game fell well short of expectations, finishing 102nd nationally (125.7 ypg). The Wolverines averaged less than 100 rush yards in Big Ten games (only Purdue produced less).
Green had some moments later in the season, including a 79-yard performance in an overtime win at Northwestern, and made his first start in The Game, rushing for 47 yards on 12 carries. But his impact was marginal.
"It was an OK season," Green said. "I could have done a lot better."
Michigan hired offensive coordinator Doug Nussmeier to, among other things, shape up a rushing attack that hasn't consistently met coach Brady Hoke's vision. Hoke wants Michigan to overpower teams between the tackles, like it used to, but the Wolverines' rushing production has dropped in each of the past two seasons.
This spring, Green and the other backs are learning Nussmeier's system, which thus far has them focusing less on carrying the ball.
"With this offense, it's real fundamental with the pass protection," Green said. "Last year, it wasn't as strict. They're trying to have pass protection first and run the ball second."
It makes sense after Michigan allowed 36 sacks in 13 games, tying for 105th nationally. The Wolverines recorded the worst net rush total in team history (minus-48) in a loss at Michigan State, and the following week at minus-21 against Nebraska. The offensive line received most of the blame, but the coaches are demanding more from the running backs to keep Devin Gardner, Shane Morris and the other quarterbacks upright this fall.
Green also noted that Nussmeier wants a "1-2 punch" at running back, a departure from his predecessor, Al Borges, who preferred one featured back. After Michigan's poor showing in the Buffalo Wild Wings Bowl against Kansas State, Green said that he and fellow back De'Veon Smith would return this year and "get it done."
Before the spring, Hoke called Smith and Green, who had 26 carries last season, "two guys we're excited about." Although several other backs are competing, the two sophomores with similar builds and running styles could have the inside track to top the depth chart this fall.
"On and off the field, we're brothers," Green said.
Green might be a leaner runner these days, but his objective hasn't changed. He still wants to be the guy who bulldozed his way to 41 touchdowns during his final two high school seasons.
"The power ain't going nowhere," he said with a laugh. "I definitely have a lot more energy and stamina. Faster, stronger, more explosive, I just feel great."