McKinnon will be a free agent after this season, his fourth in the NFL. He led the Vikings with 539 rushing yards in 2016 but averaged only 3.4 yards a carry while dealing with an ankle injury that sapped much of the explosiveness he flashed at the end of 2015. This offseason, the Vikings signed Latavius Murray in free agency and spent a second-round pick on Dalvin Cook, putting two high-priced assets in competition with McKinnon for playing time in 2017.
For his part, McKinnon is making a few changes before the start of the season. He spent much of the spring training with Peterson at his gym in Houston, adding muscle he believes will help him ward off nagging injuries in 2017. McKinnon, who said he played at around 200 pounds last season, said he weighed in at 212 pounds on Monday.
The increase has come through weight training, McKinnon said, and "doubling up my portions" of healthier protein. He's hoping to stay near his current weight as he heads into the season.
"When I was 200 or 198, I was just getting dinged up," he said. "As the season goes along, for 17 weeks, it gets hard on the body, so I'm trying to keep it on for that purpose. I feel good."
The Vikings haven't had much chance yet to see Murray as he continues to rehab following offseason ankle surgery, but Murray said last week he should be able to start running on flat ground this week and should be in line to return for training camp. The Vikings can part ways with Murray after this season, incurring just $1.1 million of dead money, so this year is a pivotal one for both Murray and McKinnon in Minnesota.
"I think it really just starts with the offseason that I had, and Coach Brent [Salazar] in the weight room, just on me every day about moving the weight fast, making sure I've got that pop to be explosive," McKinnon said. "It feels good to be back out here, and I'm looking forward to the season."