Who needs a treadmill when you have miles of shoreline? Running on the beach can get you into great shape. Take it from lifeguard Benjamin Guss, 25, of Del Mar, California, who recently qualified to compete in this year’s Iron Man triathlon (yes, that means swimming 2.4 miles, biking 112 miles, and then running a marathon — consecutively) in Kailua-Kona, Hawaii.

Beware, shoeless Joes. If you choose to run barefoot, keep your workouts brief at first to allow tender soles to build up calluses. “You can get blisters, even burns, from hot, soft sand,” says Guss.

“I like to run barefoot, but for more than a couple miles, I wear shoes.”
Know your sand. “In soft sand, one mile is like two,” says Guss. You may work foot and leg muscles you don’t always use, so start slowly. And hard sand can be as tough on your legs as the road, so wear running sneakers.

Pick the right time to run. “My favorite time is in the evening,” says Guss. “The wind dies down, and the sand isn’t that hot.”

Work harder. Fill small bags with sand to use as hand weights.