A woman exercises at home with the help of an online course.

The fitness industry was turned on its head in 2020.

As the Covid pandemic entered the U.S. in March, Americans quickly realized their gym routines were no longer going to be sustainable. Fitness studios ranging from New York Sports Clubs to SoulCycle held their final group classes, as they were forced to shut down to try to curb the spread of the coronavirus. And their users were forced to search for alternative ways to break a sweat in their basements or bedrooms, to try to alleviate Covid-related anxieties.

Sales of health and fitness equipment more than doubled, to $2.3 billion, during the span of March to October, according to data from The NPD Group. Treadmill sales skyrocketed a whopping 135%, the group said, while sales of stationary bikes almost tripled. Retailers from Target to Dick’s Sporting Goods could hardly keep items like 10-pound weights and jump ropes on their shelves.

Now, companies from Peloton to Lululemon to Apple are betting that the Covid pandemic has permanently changed how people will exercise at home. And, so far, the numbers seem to back up their bets.