4. You'll lose more weight while slashing workout time.
Kettlebell workouts can tighten and tone your whole body, but the dynamic all-muscles-on-deck movements also burn a heck of a lot of calories—on par with running a 6-minute mile, according to researchers at the University of Wisconsin-La Crosse, who evaluated the energy output of a typical kettlebell session. In their tests, exercisers burned about 20 calories a minute, or 400 in a 20-minute session.
5. You'll realize you're stronger than you thought you were.You might have never reached for a dumbbell heavier than 5 pounds before, but Kleidman suggests women start with a 15-pounder and a 25- to 30-pounder when you switch to kettlebells. You'll want to use the heavier weight when the power is coming from your legs (like with the swing, once you get the hang of it) and the lighter weight during a move where your arms are emphasized, such as presses or a halo movement around your head. When you're combining momentum with the strength of multiple muscle groups, you can lift more weight than you think you can. After all, you probably wouldn't think twice before picking up a 40-pound toddler.
6. Your posture will improve.
Using so many muscle groups in conjunction means your core has to stay engaged 360 degrees to stabilize each and every movement. Good form is essential in kettlebell workouts, so stop and rest if you feel like yours is deteriorating. The number one thing to keep in mind is that the whole structure of your back and abs should unconsciously stay straight, as though you're wearing a stiff corset. Any forward bending you do should come from your hips or the crease at the top of your leg, rather than from an arched back. Signals that you need to stop your workout include feeling like you can't hold onto the kettlebell securely (hint: skip the hand lotion pre-workout) or your arm shaking excessively in an over-the-head position.
7. You'll boost your rear and flatten your abs in one move.
The kettlebell swing is the foundation for many other kettlebell exercises, and it simultaneously firms your butt and your abs. Here's how to do it: Standing with your feet hip-width apart, your hips and knees slightly bent, and your back and arms straight, pick up the kettlebell by the handle with both hands, knuckles facing forward. Hinge forward from the hips and swing the bell back between your legs, then exhale, straighten your legs, and pop your hips and pelvis forward to propel the kettlebell upward to about chest height (that's the butt-toning part). As you lower the kettlebell, your abs will contract—like a built-in crunch. Continue with one fluid movement as you lower back to the start and repeat. (It's okay to start with smaller swings to build the momentum until you get the hang of the movement and can swing it to chest height.) Once you're comfortable with the movement, try to swing the kettlebell with one hand, alternating hands with each rep (both hands come to the handle on the upswing, and one releases as you swing down).
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