If you think you need weights to build muscle in your legs, here’s a welcome update: You don’t.

In the video above, Men’s Health Fitness Director BJ Gaddour, C.S.C.S., demonstrates the eccentric single-leg sliding leg curl. 

“It’s one of the safest, most effective ways to work the hamstrings and prevent hamstring strains,” Gaddour says.

All you need to perform the exercise is your bodyweight and a slider

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“You can also go with a sock on a wooden floor, or a paper plate on carpet,” Gaddour says. “Any way we can mimic the sliding action, creating friction and smooth movement to really fire up the hamstrings.”

The eccentric single-leg sliding curl is a great way to build up to doing the more challenging single-leg sliding leg curl. For the latter, you use the slider to perform both the eccentric and concentric portions of each rep, rather than just the eccentric part.

Start out by performing the move for one to two minutes on each leg. 

“Once you can do this for multiple sets of two straight minutes on each side, taking a minute rest between sides, you’re ready to start taking a gander at the true one-leg option,” Gaddour says.