As people enter their forties and fifties, muscle mass starts to decline because of aging and, in some cases, decreased activity levels. Muscular atrophy can also occur because of health conditions, such as joint pain. As we age, it’s important to increase or maintain muscle mass through strength training, not only because it helps burn calories, but also because muscle mass is essential for strength and balance.
You'll also build muscle to fill out your arms and firm them up. “Generally, when people are complaining about underarm jiggle, they’re usually referring to the area that is governed by the tricep,” says Williams. “If the jiggle or looseness in that part of your arm is due to a lack of muscle, then strengthening and building muscle in your tricep will also create some change in the aesthetic of that area.” She recommends performing triceps push-ups, extensions, and dips to hone in on that area and add some muscular definition to your arms.
Exercise can have a number of emotional benefits. Stress can be caused by elevated levels of the hormones cortisol, adrenaline, and norepinephrine. Exercise lowers these hormones, and increases serotonin, otherwise known as the happy hormone, which helps reduce stress. Working out can help keep depression and anxiety at bay. Plus, coping with mood disorders that are often associated with stress can be a little bit easier when you are in good physical shape.
The workout includes a dynamic warm-up to get your blood flowing and prep your body for the rest of the work ahead, and a cool-down to help you slow back down and wrap it all up. If you want to make the workout more challenging—maybe you've done it a handful of times and are ready to turn things up a notch—add weights to the lunge and squat movements. You can also, like Sims said, add another round of the main strength circuit.
Do the standing "V" raise. The standing "V" raise can help you burn fat while working your shoulder muscles. Pick up a dumbbell with each hand and stand with your feet shoulder-width apart. Start with your arms at your sides and slowly raise them upwards in a diagonal "V" shape. Keep your arms straight and bring them up until they are parallel to the floor. Hold this pose for one second, then lower your arms. Do 2-3 sets of 12-15 reps.
The skin also serves as a release point for heat. (See “Why Does My Face Turn Red When I Exercise?” for more on that.) When you exercise, your muscles generate a lot of heat, which you have to give up to the environment so your body temperature doesn’t get too high, Hackney says. The heat in the muscle transfers to the blood, which shuttles it to the skin; it can then escape into the atmosphere.