If you’re lucky enough to live near the ocean (jealous!) you might want to spice up your spring and summer workout routines by exploring a workout that’s also an undersea adventure: free diving.

Free diving is often likened to scuba diving without the mask; divers head down to the ocean floor on the power of their own lung capacity alone. Frequent divers enjoy all the benefits of swimming (cardio and muscle training galore), plus a respiratory workout you just can’t get anywhere else. Divers call the practice soothing, exciting, and way more raw than running on a treadmill or swimming in a chlorinated pool; after all, the floor of the gym may be harboring life forms, but they’re probably not fish and coral.

Celebrity free-diving devotees include Hayden Panettierre – make like her and give it a try!

To find classes near you (this is one sport you definitely don’t want to go DIY on) check out the info on freediving at the USAA.