Burn Calories in the Pool (No Laps Required!)

Why fry in scorching summer temps when one of the best ways to tone up can be found below the water's surface? "The key is that water offers heavy resistance," says Igor Porciuncula, the cofounder of Boot Camp H20 in Los Angeles—12 times the resistance of air to be exact. That means these swimming exercises your moves engage more muscle fibers and burn more calories in a shorter amount of time.

How to do it: Do Porciuncula's water aerobics exercise circuit twice through for sexy arms, tight abs, strong thighs, and zero dripping sweat.

What you'll need: A kickboard such as Speedo Team Kickboard ($15, amazon.com) and a cute suit, of course!

Targets shoulders, arms, abs, and hips

• Standing in shallow end, simultaneously sit back into water, treading with hands out to sides, and lift both legs together so that you fold at hips to create a wide V shape, with head and toes just above surface.
• Quickly bring knees to chest — or bring legs as straight as you can toward chest to make V less wide—then extend legs to return to V position.
• Do 15 to 20 reps. Continue treading with hands for 1 minute.

Make this swimming exercise easier: Skip knee tuck and simply hold V position for 1 minute. (Related: Try This Crazy-Creative Pool Float Workout Next)

Targets abs, obliques, hips, and legs

• In deep end, hold on to edge of pool with right hand so that body is perpendicular to edge; tuck knees into chest to place both feet flat (right stacked above left) against side wall of pool as high as possible.
• Maintaining hand grip throughout the water aerobics exercise, jump feet off wall and extend legs as you engage abs to bring body as parallel to surface as possible in a side-plank position (left hip now stacked above right).
• Return to tuck and continue for 1 minute. Switch sides and repeat for 1 minute. (See how to do a burpee—the right way.)

Targets back, shoulders, arms, chest, and abs

• Sit on kickboard with knees together, legs dangling or skimming bottom of pool.
• Extend arms in front of you, palms facing away from each other, then sweep arms out to sides (as if doing a breaststroke).
• Continue stroking across pool for 30 seconds, then switch stroke to go in opposite direction: Bring arms out to sides with palms facing forward, elbows slightly bent, then sweep arms together in front of you.
• Continue for 30 seconds, squeezing shoulder blades throughout the swimming exercise as you push forward and back.

Targets back, arms, abs, butt, and legs

• With your back to edge of pool, hold kickboard with both hands so that it's vertical (rounded edge up) and half of it is below surface of water.
• Push off wall with feet, holding kickboard in tombstone position, and kick as hard as you can toward opposite side of pool.
• Continue for 1 minute.

Make the water aerobics exercise harder: Hold kickboard horizontally and completely submerged. (Related: You Can Do This No-Swimming Pool Workout on Dry Land, Too)

Targets abs and legs

• Tread water in deep end of pool, arms out to sides and legs extended beneath you.
• Engaging abs, squeeze legs together and sweep them backward, bending knees slightly, then quickly extend them forward (like a dolphin's tail); counterbalance motion by sweeping arms through water in opposite direction of legs.
• Continue for 1 minute.

Swimming exercise tip: Your whole body should crack like a whip; initiate the movement from your core, not your legs.

Targets back, shoulders, arms, and abs

• In rib-deep or waist-deep water, stand with feet wide, grasping each end of kickboard with thumbs on top; hinge forward from hips 45 degrees with back flat and elbows bent by sides so that board is in front of chest.
• Push kickboard diagonally down under water, extending arms and squeezing abs, then bend elbows to scoop board back up to chest like a biceps curl.
• Continue for 1 minute.

Swimming exercise tip: Splash as little as possible to ensure you're focusing on your core and arms. (Related: Cool New Water Workouts That Have Nothing to Do With Swimming)

Targets abs, butt, hips, and inner thighs

• Treading water in deep end, grasp each end of kickboard and hold it above your head.
• Extend legs below you.
• Flexing feet, bend knees to bring heels toward butt and quickly press legs down and diagonally outward to thrust body out of water a bit, toes pointed.
• Extend legs below you; repeat for 1 minute.

Make this water aerobics exercise easier: If holding kickboard overhead is too difficult, just raise hands above head or let them float by sides.

Targets triceps, abs, and obliques

• Begin with your back facing side wall of pool and place palms on edge behind you, fingertips facing forward; bend left knee to place left foot flat against wall and raise straight right leg to hip height in front of you.
• Straighten arms to lift out of water (similar to a land-based triceps dip); lower to start.
• Do 10 reps; switch legs and repeat.

Make this water aerobics exercise easier: Keep both knees bent and both feet flat on wall. (If booty scrapes the edge, you can also do this in corner of pool.)