Working out with dumbbells and other types of free weights can help you lose fat from your arms. There's just one catch: You can't burn the fat from only your arms. It's going to come off your entire body, and which body parts slim down depends on your hormones and genetics, not on the muscles you work or how many pounds you can lift in a biceps curl.
Working out with dumbbells can help you lose fat from all over your body, including your arms. But it won't make you lose fat from your arms only.
The Myth of Spot Reduction
Spot reduction is the stuff of late-night infomercials, where enthusiastic, Spandex-clad pretty people promise that if you just work a certain body part enough it'll slim down. And, of course, it'll slim down faster if you buy whatever they're selling.
Unfortunately, the idea that you can target fat loss to a single part of your body by exercising that body part — aka spot reduction — is just a big, pervasive and all too beguiling myth. But they do have it half right: Working out consistently is the key to slimming down all over. You just can't dictate which areas your body chooses to slim down first.
Although the very nature of lifting dumbbells means that only working out with them might not be enough for fast, measurable slimming, they can provide a significant and meaningful contribution to your weight loss efforts — not to mention creating some pretty impressive arm muscles that will be revealed as any excess body fat melts away.
Dumbbells Help With Weight Loss
There are three ways lifting dumbbells can help slim down your arms. The first is simply by burning calories. If you establish a calorie deficit by burning more calories than you take in, your body will start to use its calorie reserves — in other words, your body fat — as fuel.
Although lifting weights isn't the most impressive calorie burner, consistency is key when it comes to reaching that calorie deficit, and every little bit adds up. The American Council on Exercise (ACE) calorie counter estimates that if you weigh 160 pounds, an hour of weightlifting will burn about 217 calories.
If you weigh more or lift at a higher intensity, that number goes up. For example, if the same person switches to "intense" mode — which ACE doesn't define, but usually translates to heavier weights, fewer breaks and more compound exercises to work more muscle groups at once — she'll burn a much more impressive 435 calories in an hour of weightlifting.
If you weigh 200 pounds, that hour of normal weightlifting will burn closer to 272 calories — and switching on the intensity will get you in the neighborhood of a whopping 544 calories.
Metabolism and Appearance
But wait, there's more. In addition to the calories you burn while weightlifting you're also building lean muscle mass, which is four times more metabolically active than fat. Or, to put it another way, adding muscle will help you rev your metabolism and burn more calories even when you're not actively working out.
The third and final way dumbbells can help slim down your arms is a simple matter of aesthetics. Sometimes, if you're already relatively slender, adding a little muscle definition will help your arms look slimmer right away, even if your body fat percentage hasn't changed.
Do you want more proof that lifting weights really can help you slim down — even if you can't tell your body to take the fat off your arms first? Consider a study published in the December 2014 issue of Obesity, in which researchers followed 10,500 healthy men and tracked which activities had the greatest impact on the subjects' waist circumferences.
The winning answer: Weight training had the biggest impact, although it wasn't the only factor that contributed to weight loss. Ultimately, it's not weight training on its own that will help you lose weight, but weight training in combination with other healthy habits that include a nutrient-rich diet, regular cardiovascular exercise and basic self-care like getting enough sleep.
Which Exercises Should I Do?
If you enjoy hitting the dumbbells, which exercises should you do to help you along in your quest for leaner arms? There are two answers to that.
First, compound exercises that recruit multiple muscle groups will help you do more work in less time, which in turn means more calories burned. Head straight for exercises, such as chest presses, overhead presses, dumbbell rows, pullovers, deadlifts, squats, lunges and the like. You can even use dumbbells to mimic a few kettlebell movements, such as kettlebell swings.
Some of those exercises will work your triceps and biceps, the two muscles that give your arms most of their shape. But you can add in extra workouts for those muscles to develop them even more — think triceps presses, biceps curls, hammer curls, concentration curls, triceps kickbacks, headbangers and so on. Throw in a few shoulder exercises, such as rear deltoid flies, front raises and lateral raises, to help create a balanced-looking upper body.
Read more: 5 Dumbbell Moves You Haven't Tried Before
Even if you don't plan to use dumbbells as the core of your weight loss program, you should still do some sort of strength-training exercises for every major muscle group at least twice a week. The Department of Health and Human Services says so.
How Often to Lift
Did you catch the earlier mention of some inherent limitations when it comes to using dumbbells for the core of your slim-down workouts? That's because your muscles actually get stronger in the rest period between workouts, not during the workouts themselves. Each muscle group needs at least a full rest day between workouts — more if you've managed to make yourself very sore.
That means that, at best, you can do a serious full-body dumbbell workout just three or four times a week (depending on which day you start). You can increase the duration and frequency of your dumbbell workouts if you use a split method, which means only working a few muscle groups in each workout — so those groups can be "in recovery" when you work different muscles the next day.
However, that sort of method is very intense and can create the sort of soreness that delays your next workout. To put it another way, it's certainly not for beginners or anyone who's not both disciplined and focused in their dumbbell workouts.
For most beginners, starting with two full-body workouts a week, with one or two sets of eight to 12 repetitions per exercise, will be plenty. As you build strength and stamina, you can work up to three lifting sessions per week and then start to consider the possibility of introducing splits.
- ExRx.net: "Spot Reduction Myth"
- American Council on Exercise: "Physical Activity Calorie Counter"
- University of New Mexico: "Controversies in Metabolism"
- Obesity: "Weight Training, Aerobic Physical Activities, and Long-Term Waist Circumference Change in Men"
- Health.gov: "Dietary Guidelines for Americans, 2015-2020: Appendix 1. Physical Activity Guidelines for Americans"