If you have an opportunity to train outside, head for some actual hills for some fresh air—and a powerful workout that’ll keep you challenged. Try to find a hill that’s about a tenth of a mile (150 to 200 meters) in length, and do about eight to 10 repeats. Keep these form tips in mind from Alan Bautista, a certified running coach based in New York City.

1. Look Up

Keep your shoulders squarely facing the hill, head straight and eyes pointed either straight ahead or at a land mark somewhere up the hill. “There shouldn’t be any rotational movement,” Bautista says.

2. Use Your Arms

“Keep your arms tight to your body and use an exaggerated, piston like movement with every step to help drive you forward,” Bautista says.

3. Shorten Your Stride

Your power is derived from flexion at the hips, fully engaging your quads,” says Bautista. Try to land closer to the ball of your foot, flexing your calf muscles to help extend your foot and ankle.