Visit your doctor. Certain medical issues may be contributing to the buildup of fat in your arms and the rest of your body, including a thyroid problem or diabetes. Your doctor can also test your hormone levels with a simple blood test to see if there is an imbalance. Low testosterone can contribute to weight gain in your arms, thighs, and lower abdomen.
A While using weights are one of the most effective ways of losing arm fat, it comes with the worry of whether your muscles would bulk up. While this is a common concern, building muscles doesn’t happen overnight and takes hours of intensive workout at a gym. If you, however, still concerned, you can lose flabby arms by opting for exercises that don’t include weights. Exercises such as pushups can help in this case, since you will use your own body weight to tone your arms. Tricep dips will also help you lose flabby arms without bulking up. Yoga is another great alternative.
Bend your knees to lower down into a split squat. Your left knee should ideally form a 90-degree angle so that your thigh is parallel to the ground, and your right knee is hovering above the floor. (Quick position check: your left foot should be stepped out far enough that you can do this without letting your left knee go past your left toes—if you can't, hop your left foot out a bit farther away from the bench.)
If you're ready to move on from classic Bulgarian split squats, Swan's amped-up variation gets your upper body in on the action for a true total-body exercise. "This combination move works your legs, butt, chest, back, arms, and core," she says. "And it not only hits all the major muscle groups—it also lets you work on balance." Give it a shot and you'll see why.