Remember summers as a child? Lighting sparklers to write in the night sky, doing cannonballs into the pool, and letting a slice of watermelon drip all over your hands can all rekindle your childhood joy of summer. And there are loads of ways you can freshen up your workout routine, starting with these playful moves inspired by popular warm-weather kids’ activities.While running around your local playground as a kid, you were probably having too much fun to realize you were also getting a serious workout. Next time you are at the park, hit the monkey bars. Be sure to climb forward at full speed each time to get the most out of your workout.Cartwheels make it nearly impossible to stay in a bad mood. So if you plan to work out after a tough day at the office, an awkward run-in with your ex, or a sleepless night, this exercise will turn your frown upside down, literally. Cartwheels have a lot of fitness value , too. They work your hamstrings, core, and shoulders and require balance. If you haven’t done a cartwheel since sixth grade, start slowly and become confident with your hand placement before you start flipping around.“A — my name is Alice, and I come from Alabama, and I sell apples…” Once upon a time, you may have been able to jump your way down to “Z — my name is Zelda” without breaking a sweat, but doing the same activity today can give you as much of a workout as running. Plus, it’s a great way to improve agility. To introduce jumping rope into your fitness routine, try 10-minute intervals, resting after every 20 rotations. When you get back in the swing of things, vary your jumps to include heel taps, scissor jumps, and ski jumps. Bonus: A jump rope fits easily into a gym bag or luggage.When was the last time you saw a firefly and tried to catch it? On a clear summer evening, get out of your chair and chase some fireflies. In addition to getting your muscles moving in a relaxing and low-impact way, this simple pleasure does wonders for your mood and well-being.It may not feel like much of a workout, but 30 minutes of hula hooping will leave you out of breath. By doing a series of hula hoop exercises, you can tone muscles in nearly every part of your body. Start out with the basic side-to-side hip movement until you have good control over keeping the hoop up on your waist. Then vary your workout by incorporating a front-to-back hip motion or the lower-back bump Grab a piece of sidewalk chalk for some fitness fun. Jumping in and out of the hopscotch board boxes will work your brain’s connection with your feet and can improve your foot-eye coordination and lower-body reaction timing. If done correctly, hopscotch also provides a good cardio workout. The faster you jump, the bigger charge your heart rate will get. Exaggerate your bend and hop to really engage your butt and legs. You’ll be having so much fun playing that you’ll forget you’re really doing jumping squats.Wheelbarrow races were a highly competitive category in any elementary school field day, but this game is also very effective at raising your heart rate and toning your upper body. Wheelbarrow walks target your chest, triceps, and shoulders. The exercise also engages your abs and lower back, since they’re called upon to keep you upright and stable as you move forward.To do a wheelbarrow walk, you’ll need a workout partner. Place your arms on the ground to serve as the “wheels.” Hold your torso in a plank position while your partner holds your ankles as if they were the handles of a wheelbarrow. Walk forward on your hands, keeping your head straight. Start out with three sets of wheelbarrow walking for 10 to 30 yards, and make it your goal to build up to 10 walks for 50 yards each.