It strengthens the brain. Studies have found that working out can lessen the severity of memory problems in older adults, and even decrease the risk of diseases like Alzheimer's. It can also have a positive benefit on the brain function of younger people. Research out of New Zealand shows that exercise improves executive function -- the general brain processes that include planning, memory, reasoning, problem-solving and more.
“Body fat is structurally important,” explains Stefanie Mendez, R.D., co-founder of Matriarch, a women's fitness and nutrition service. “It cushions our organs and insulates our body for temperature control and also is our body’s source of energy reserves. Beyond that, fat is needed for the production of hormones and reproduction functions.” And that fat can show up in your thighs, your belly, and, yes, your upper arms. Where it goes is partly due to genetics; if your mom has arm fat, science says you have a 62 percent chance of inheriting that trait.