For better form, David Siik says to stay a few inches away from the front of a treadmill.

Runners — a group of people accustomed to bloody nipples, blackened toenails and mid-route diarrhea — seem to become embarrassed by only one thing: treadmills.

“They say, ‘I can’t get on one.’ There’s this shame,” says David Siik, creator of Equinox’s new Precision Running program. He has plenty of reasons athletes should get over their hang-up: Treadmills are gentler on the joints than unforgiving sidewalks, they allow groups of different abilities to run “together,” and they make it possible for a coach to monitor an athlete for every step of a run. His absolute favorite thing about treadmills? “You can calculate anything — it’s like running on a computer,” Siik says.

But to get the most out of the info and experience, you have to use the technology correctly, he adds. Here’s his list of treadmill don’ts:

Don’t show up without a plan. Playing it by ear is a recipe for an ineffective workout, Siik says. Even if you’re not able to complete what you set out to do, you’ll wind up better equipped for next time. “I’ve learned from my mistakes,” Siik says.

Don’t start with a sprint. “It doesn’t give you anywhere to go,” Siik says. Get your body warmed up, and then introduce intervals systematically.

Don’t forget to up your speed before an interval. Treadmills take time to get faster, Siik says. So you’re cheating yourself if you don’t press that arrow at least a few seconds before you’re ready to go all out.

Don’t run too close to the front of a treadmill. “It hunches your posture, shortens your stride and makes you have funny arm movements,” Siik says.

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