Exercise is good for you, but it might do more than you think. New research suggests that deciding to get fit today may help your brain well into the future. Brain age is a growing concern for people reaching middle age and beyond. You may even be expecting to experience memory loss, dementia, or other forms of cognitive decline. It’s entirely possible you believe you’re destined for this outcome and that it is simply a “natural” part of aging. Your brain will go through some natural changes with age, just like the rest of your body. But by getting fit now, in middle age, you might be able to keep your brain healthy for decades to come. A new study, published in Neurology, suggests that getting at least an hour and 15 minutes of moderate-to-vigorous physical activity per week or more may help promote brain health and preserve brain structure. …