When Kelly Amerson López discovered aquatic exercise, it was nothing like she expected. She was in her 30s and a fitness buff who ran half marathons in Central Park. One day at the gym, she stumbled upon a group of people using the pool. They were running in place and pivoting in chest-deep water, and the instructor sounded more like a drill sergeant than a water aerobics teacher.
“They looked like they were getting a great workout,” she said.
Ms. López began taking water exercise classes and found that running in deep water helped her develop more upper body strength than running on land. Now 68, she’s incorporated pool exercises into her workout routine ever since.
Pool workouts are often associated with seniors or people recovering from injuries, but they can also be a form of high intensity interval training (HIIT) that is different, and lower impact, than what you experience on land. For example, it’s easier to balance on one foot without falling or do explosive jumps in which your knees come all the way up to your chest.
In addition, “it’s 360 degrees of resistance in every direction,” said Laurie Denomme, a fitness instructor from Bradenton, Fla., who has been teaching aquatic exercise for 30 years. “Whether you move up, down, left, right, circling, you are always working against resistance.”
Why exercise in water?
Aquatic exercise refers to any type of workout that takes place in a body of water that isn’t swimming laps. It’s typically done in chest-deep water, so you can push off the bottom or jog in place while still benefiting from full-body resistance.
Exercising in water doesn’t get your heart pumping as fast as when you do it on land because of the hydrostatic pressure of water, which pushes blood back to the heart. While you might not feel like you’re getting as good a workout, there’s reason to believe you are: Some studies have shown similar improvements in fitness (both aerobic and anaerobic) between aquatic exercises and treadmill workouts on land.
Aquatic exercise is particularly beneficial for those who can’t do high-impact activities on land. In the water, even people with reconstructed knees can run in place and perform jumping jacks.
“You don’t deal with the same type of ground reaction forces that you do on land,” said Elizabeth Nagle, an associate professor at the University of Pittsburgh who has spent her career studying aquatic exercise. “So it’s much gentler on the joints.”
How to get started
The only thing you need to begin an aquatic exercise program is a pool and a bathing suit (or a shortie wetsuit, if you prefer). Ms. Denomme said the water temperature should ideally be between 83 to 86 degrees Fahrenheit, because it’s warm enough that your body doesn’t have to adjust, yet cool enough to prevent overheating.
She suggested starting without equipment, so you can learn how to use the resistance of the water to optimize your workout. Moving slowly through the water, like when you’re jogging in place or doing leg exercises, is great for mobility and balance. Moving more quickly, like with jumping jacks, has strength and cardiovascular benefits, Ms. Denomme said.
Once exercising without equipment starts to feel easy, she recommended using a pair of webbed aqua gloves when you do your workout; they increase resistance while helping you to build upper body and core strength. She suggested going with nylon, like those by H2O Wear and Hydro Fit, as opposed to neoprene (which causes too much resistance). Aqua gloves cost between $10 and $20 a pair.
Most people work out in the shallow end of a pool, although some eventually switch to the deep end, using a flotation belt, to make a routine even more challenging in terms of balance and stability. Many community pools and gyms offer aquatic exercise classes. For workouts you can listen to with waterproof earbuds, check out Water Exercise Coach on YouTube or the PoolFit website.
To get started on your own, try this workout in chest-deep water, which should take about 20 minutes total. Add or subtract time or repetitions to make it easier or harder. Hydration is still important with aquatic exercise, especially on a hot day, so be sure to drink water after the workout.
Before starting, warm up for about five minutes. Spend one minute jogging in place in each of the foot positions listed below to allow different muscles to be stretched and strengthened, Ms. Denomme said. Move directly from one position to the other, with no rest in between, at a moderate pace.
Feet slightly wider than your shoulders
Feet close together, side by side
Right foot slightly ahead of your left foot
Left foot slightly ahead of your right foot
Toes pointed outward diagonally, like a duck
This full-body routine involves high-intensity intervals broken up by active recovery and can be done with or without webbed gloves. If you feel unsteady during any of the movements, hold onto the side of the pool.
The faster, more intense exercises in this workout should been done at about 80 percent of your capacity, once you feel comfortable with them. Try to do the whole routine without breaks, using the slower exercises to catch your breath. If it feels too difficult, take breaks between movements or slow them down.
Stir the water, one minute in each direction: Stand with your feet hip-distance apart and circle the water with both hands like you’re stirring a giant pot of soup. Move both arms together or alternate one arm at a time. Circle clockwise, then counterclockwise.
Hilary Achauer is a freelance writer focused on fitness, health, wellness and parenting.