One day at the park with my dog, I stumbled upon an amazing workout, completely by accident. As she ran around, I decided to try some push-ups on the swings. And then, well, you’ll find out in a moment.

As I played around with different exercises on the swings, I put together a very effective workout that burns fat and helps build lean muscle.

Next time you’re at the park with your kids (or, in my case, a dog) give this fun workout a try.

1) Pushup-place each hand in a swing and simply do a pushup. To make the movement more challenging, keep the swings closer to the ground. To make it easier, walk the swings forward so they are higher up. Make sure you keep your butt and stomach very tight throughout the entire movement. This pushup is much more unstable than a regular pushup because you have to stabilize yourself. This means more work for you core!

2) Inverted row-to perform this you’re going to get in a reverse pushup position (the front of your body with be facing up). Grab the chains or cables, keep your body straight, and pull yourself up. Imagine doing a reverse pushup. To make it easier, walk the swings back so they are higher above the ground. The closer the swings get to the ground, the more challenging the movement. As with the pushup, make sure your butt and stomach are tight the entire time.

3) Suspended lunge-stand in front of a swing and place the top of one foot in the swing. Your front foot should be about 2 feet in front of the swing. Important: that back foot resting in the swing is there for support. Don’t put weight on it or push off with it. Keep your torso tall, butt and stomach tight, and lower yourself to the ground keeping the weight on the heel of your front foot. Once the top of your thigh is parallel to the ground, press back up hard through your heel.

4) Knee tucks-get in a pushup position with your hands on the ground and the tops of your feet in a swing. Keep your stomach tight and pull your knees to your chest, focusing on your stomach doing the work.

Perform 10 reps for each exercise (10 reps for each leg with the suspended lunge) and don’t rest between exercises. Once you do 10 reps for the knee tucks, rest 1-2 minutes and then repeat the circuit 3-5 more times.