At the gym, I see a lot of people working hard to tone up, trim down and get stronger. But I also see folks making exercise choices under false assumptions -- some based on outdated advice, some because they're following the lead of other members, and some just because they don't know any better. In fact, you may be surprised at the muscles you’re actually working during your favorite exercises.
Here, some of the most commonly misunderstood moves -- and while they’re still safe and effective ways to tone up, they may not exactly be doing what you think they are:
They seem like they should be a great shoulder workout -- I mean, you are swinging a weight around -- but kettlebell swings are actually all about the hips, with the power coming from the forward thrust of your glutes and hamstrings. Basically, your arms are just along for the ride. If your aim is to train your upper body, use that kettlebell for overhead presses or bent-over rows.
More: 5 Kettlebell Mistakes You're Probably Making
The modified pushup is the on-your-knees version of the original. You'd think this would work the exact same muscles as a regular pushup, right? Not exactly. While you’re still working your chest, triceps and shoulders, you're not targeting your core like you would in a regular pushup -- especially if you let your hips creep up. If your goal is to work up to a regular pushup or just reap the same benefits, start with an elevated pushup instead -- you can even start by leaning into a wall. Then work your way down to lower surfaces, like a bench. And remember, performing just a few reps with perfect form is way better than cranking out a bunch of imperfect ones.
More: The 13 Best Exercises for Women
There's no doubt that leg lifts are a challenge, ostensibly for your lower abs. But here's a crazy reality check: There's no such thing as "lower abs" -- anatomically, your rectus abdominus (that's the six-pack muscle) is one long muscle, so if you're working it, you're working the whole thing. But here's the thing: This move may put added stress on your hip flexors (you'll know it if you feel pinching in your hip creases during the exercise). If that's the case, you can still work your whole core with exercises like planks, bridges, chops and flutter kicks.
More: 10 Abs Exercises Better Than Crunches
I LOVE these! Whether done with full bodyweight or supported by a band, pull-ups arephenomenal exercises for your ... back muscles. Surprised? It's not that your arms and shoulders aren't working (they are) but the bulk of that pulling action comes from the large latissimus dorsi muscles that wing out from your mid-back to your waist. In fact, if you just focus your attention on the lats when you're doing the exercise, you might find you can bang out a few extra reps. Looking for more arm-focused work, too? Add some standing cable biceps curls and triceps extensions to your routine.
Hurling a heavy ball at the ground may seem like a challenge for your arms and shoulders, but it's actually all about your back and core. In this extremely satisfying move -- I dare you not to grin that first time the ball smacks the floor -- the effort is coming from your lats (yes, those again), while your ab muscles work hard to stabilize against the force of the action. If your goal is a shoulder workout, a more effective move would be alternating front arm raises.
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