The truth about cold workouts

Deep freeze

This January brought winter back. The US East Coast faces another storm this weekend, and here in Berlin, it’s the coldest start to the year since 2010. Sliding across the sidewalks on my commute, I started to wonder whether the frigid temperatures were at least helping me burn some extra calories.

The answer is not so straightforward. Exercise in cold environments does mean the body has to maintain its core temperature while it produces energy, which requires more energy expenditure, according to Original Posth8Cqm1N5TQYKy2gBr-_gKDtusLJJSUq/17" target="_blank" rel="noopener noreferrer" shape="rect">Lee Brown, a senior lecturer in strength and conditioning at the University of East London.

Exercising in the cold activates brown fat, which makes heat via a process in the cells called non-shivering thermogenesis, he says.

Yet while that burns more energy, it’s a small difference in the grand scheme of things, says Simon Hodder, a professor in environmental ergonomics at Loughborough University. “The benefits of being cold are not going to offset a cheeseburger,” he says.

The big benefit comes in simply continuing to exercise even though it’s nasty outside, Hodder says. To do that safely, he advised making sure to warm up the muscles and joints beforehand, and taking care to avoid falls on slippery sidewalks and paths.

A warmup should involve movement like arm circles and high steps, according to Harvard Medical School, rather than static stretches.

For winter sports like skiing that involve being outside for longer periods, the challenge is to dress for comfort while stationary but without overheating during exercise, Hodder says. That means layers and vents in outdoor gear. Similarly, winter runners need to think about how warm they’ll be 20 minutes into their run, not just how cold they are when they step out the door.

“In the chairlift up, you’re static, you need really quite high levels of insulation to keep you comfortable,” Hodder says. “But then when you come down, you’re actually doing quite high intensity exercise depending on how you do it, and so you generate lots of heat.”

In all cases, Hodder advises keeping the hands, head and feet well covered up. Nerve thermoreceptors in the face also play an important role in determining the body’s comfort outside.

Ultimately, repeated outdoor exercise over the winter will make the body more efficient at shepherding its energy to deal with the cold, says Brown. I plan to test this soon with some skiing — and a few schnitzels. — Naomi Kresge