With the summer sun beating down and temperatures soaring from morning until late afternoon, you might be tempted to take your workout into an air conditioned gym. The height of summer can be tough on outdoor workouts like running and cycling, but that doesn’t mean you need to take it inside. You can actually get an intense and effective workout, while staying cool, if you’re open to hitting the water.

Water sports are one of the best parts of summer and even if you might not realize it at the time, these activities are putting you through a killer workout.

Whether you’re surfing, swimming or wakeboarding, the resistance of the water is building strength—often more efficiently than lifting weights in the gym. Water sports with boards require balance, which is great for building core strength and agility in general and practically any activity on or in the water can be turned into a great cardio workout. Add to that the rising temperatures on land and who wouldn’t want to get in a workout on the water?

In celebration of summer and the awesome strength-building powers of water, we’ve highlighted some of the water sports that are probably better—and definitely more fun—than your current workout.