Want to lose arm fat and feel like a rock star at the gym? Then you need to add this move to your exercise routine

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Welcome to our brand-new #MasterThisMove series! In each post, we'll highlight an awesome exercise and give you tips to not only do it right, but to extract the maximum possible benefits from it. "When it comes to strength training, it's not just about doing an exercise, but executing it properly," says personal trainer Nick Rodocoy. For example, you can do 50 pushups without going through the full range of motion, and you won't see the benefits-but if you do fewer pushups with better technique, you'll get way more out of the move. (Try The Pushup Progression Workout.) That's because each exercise is designed to be done a certain way in order to activate specific muscles and groups of muscles. If you do it "wrong" (or half-ass it!), you won't get the intended effect.

The first move we'll cover: the chin-up. It's a particularly challenging move for women, which is all the more reason you should not only try it, but master it. "Woman don't have as much upper body strength as men, and they have more body fat," explains Rodocoy. Together, those two factors make a chin-up a tough feat. But that's not to say us girls can't do it: "I've seen women do eight chin-ups in a row," says Rodocoy. In fact, Carrie Underwood Does Chin-Ups Like It's No Big Deal! It's just a matter of building that upper body strength you need first.

More motivation to give it a go: "It's a big bang move," says Rodocoy. "It's a compound movement, that calls upon multiple muscles at once." In other words, it's a total-body toner. Plus, it's pretty darn empowering to be able to do even one!

Rodocoy reccomends starting with an assisted version of the chin-up. If you have a chin-up machine in your gym, you can practice going through the exact range of motion you'll do once you try the move on your own. Check out the technique below.

Chin up machine on Make A Gif

No chin-up machine, no problem. Perhaps an even better way to simulate the motion of the exercise is by attaching a resistance band to a chin-up bar, like the SPRI Pull-Up Bar ($39.98, Spri.com)-you can just put it up in a doorway in your house!

band chin-up on Make A Gif

Either way, practice your assisted chin-up twice a week. Make one of those days a "heavy" day (do 6-8 reps with less weight on the machine or a heavier resistance band) and the other day a "light" day, where you take more assistance from the band or machine, but complete 10-12 reps. "This will help you to build the shoulder stability you need, so you can do it on your own," says Rodocoy.

Once this exercise starts to feel easier, you can progress to the "eccentric chin-up". Jump up (or use a box or step) and get into the ending portion of the chin-up. Then, slowly lower your body down. Hop down and then repeat. One note of caution: "Don't do more than five reps at a time," says Rodocoy. "The eccentric motion puts a lot of stress on your muscles."

Eccentric chin-up on Make A Gif

Now you're ready to attempt the real deal. "Squeeze everything tightly-particularly your butt and abs," says Rodocoy. 
"Many people flail around on the bar, but it's so much easier to move solid body than loose body."