The only thing skier Mikaela Shiffrin could control this past year was her workout soundtrack: Taylor Swift. Due to coronavirus, the two-time Olympic gold medalist and six-time world champion found herself preparing for her comeback season in her home garage using equipment hacks and video coaching. She became one more avid exerciser trying to keep fit without a gym.

Ms. Shiffrin says learning to manage situations that are out of your hands is a secret of her sport. “As a ski racer, you spend your whole career trying to control something that should be uncontrollable,” she says. “When everything lines up on a run and you’re in control of the uncontrollable, it’s the greatest adrenaline rush you can get.”

The 26-year-old took a mostly involuntary break of 10 months from racing last year. After a six-week hiatus following the February 2020 death of her father, Jeff Shiffrin, she tried to return last March, just as the pandemic shut the world down. An October back injury sidelined her further. After years of domination, she entered the 2020-21 season in unfamiliar territory: coming from behind.

“I’ve had to play catch-up all season,” she says. “For quite a while I was the one being chased. I felt like I was the one writing the playbook and everyone else was reading it. This year I have other skiers to watch. It’s been motivating to be the one chasing.”

While her European competitors trained on glaciers during the North American summer, Ms. Shiffrin barely touched skis. “My training program and schedule changed completely,” she says. Typical training trips to South America were off due to travel bans. And when the state-of-the-art gym where she trains in Avon, Colo., shut down, she scrambled to buy equipment online to create a home gym.