Swimming and Rowing
When swimming, give yourself a good push. It might feel like cheating, but giving a hard push off the wall when you turn improves your time and is also good exercise, since it "engages your thighs, quads, hamstrings, glutes, and abs," says Greg Isaacs, a competitive triathlete and the national fitness director for L.A. Fitness. "It will also give you the momentum you need to develop the rhythm that will let you glide through the water." The best method is to place your feet flat against the wall with your weight on your heels, bend your knees, then push off hard with your toes. "Be sure to keep your arms straight over your head and close to your ears so your body is as streamlined as possible," Isaacs says. "That way, you'll move through the water faster and more efficiently."
Also remember to...Start off easy. "I've seen so many people, even ones who've been swimming for years, charge right in and start tearing up the water, and they're exhausted after just 15 minutes," Isaacs says. "You will be able to swim much harder and much longer if you take some time to warm up in the water, swim a few easy laps, then stretch out a bit before you dig in."
Push, then pull, when you row. Although it's generally one of the least popular cardiovascular machines in any gym, rowing is one of the most beneficial, since it works both the upper and lower body simultaneously. But it's important to start with your legs, pushing before you pull with your upper body. "Many people start out the rowing movement by yanking backward with their arms and back," Peterson says. "Using your legs first and then engaging your upper body allows you to put more power into each stroke and takes the strain off your lower back."