You know staying fit is important, especially if you want to manage your heartburn. But who wants to exercise indoors when it’s sunny and warm outside? Fortunately, you don’t have to! It’s time to try nature’s gym for a workout that’s just as good, if not better!

1. Instead of a calf machine

Hit the hills. With just a slight incline, your calves will get a workout mere calf raises can never match. There’s no substitute for outdoor terrain, says Kelli Calabrese, a Texas-based trainer and co-author of Feminine, Firm & Fit (Great Atlantic Publishing Group 2004). “Machines are created to make it easier on you, but the ground forces you to adjust to whatever the elements have done to it,” she says. “Literally every section of a hill is different and will work your calves a little differently.” Plus, you’ll feel more accomplished when you actually climb to the top of a hill rather than just feeling like you got there on a machine.

2. Instead of circuit training on exercise machines

Get on base. Find your nearest baseball diamond and assign a different exercise for each base. Calabrese recommends beginning with side-to-sides to first base, which are performed by moving your lead leg out to the side a couple of feet then bringing your other leg in to meet it. Once you reach first, go into a sprint for second, then do 10 butt kicks while on base by kicking your feet back one at a time, trying to touch your heel to your derriere (great for the hamstrings). Now it’s time to lunge all the way to third base: Take a giant step forward as far as you can, letting your back leg bend, knee stopping within an inch of the ground; switch legs for the next lunge. When you reach third, return to side-to-sides until you touch home.

3. Instead of tricep extensions

Grab a bench. With your back to a park bench, squat down and place your palms on the bench until you’re balanced on your hands. Extend your legs out at a 45-degree angle and let your butt come down as far as it will go. Hold for a beat then complete the tricep extension by pushing yourself up just short of locking your arms. Go for three sets of 10, and you’ll feel the burn. (Speaking of burn, don’t forget sunscreen. No use getting healthy outdoors if you’re increasing your risk of skin cancer.)

4. Instead of chest presses

Do kiddie push-ups in the park. No, that doesn’t mean doing push-ups like a kid. It means doing push-ups with your young son, daughter, niece or nephew riding on your back. The child provides the resistance, and you’ll provide him or her with a human amusement park. Vary the speed of your reps, and you’ll keep your kid guessing while getting more muscle fibers involved. Gary Sforzo, professor of exercise science at Ithaca College in New York, says kids remind us how much fun being active outside can be. “Sometimes we forget how to just run and play,” he says. “It’s amazing how spending time with a kid outside makes you work up a sweat without even knowing it.”

5. Instead of squats 

Try sand plyometrics. First, get into a half-squat with your butt at a 45-degree angle (imagine a full squat as sitting in a chair). Hold for a beat then jump as high as possible. Follow immediately with a second jump. Repeat. After each jump, your feet should sink until they’re buried in the sand to create further resistance. If you can see your toes, you didn’t do it right!

6. Instead of shoulder presses

Chop wood. Two advantages: one, you tone your shoulders, and two, you’ll have plenty of wood next winter when it’s freezing and you want to build a fire. With the wood on a stable surface, put the blade near where it’s already splintering. After you visualize the target in your mind, rear back and take your best chop, making sure you have good extension throughout. (When beginning, have an experienced wood chopper on hand for s upervision and consultation on whether your eye goggles meet safety standards.)

Summer won’t last forever --  you can’t keep nature’s gym open most of the year. In fact, with extra layers and extra toughness, you can enjoy the outdoors all year round, from raking leaves for your lats to making snowmen for -- well, just for fun. Now, if you’re reading this indoors, we believe the front door’s that way!

Eric Butterman has written health articles for more than 20 publications, including Glamour, Men’s Fitness and Shape.

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