It is common knowledge that exercise helps boost your metabolism at any age, especially muscle-building and strengthening resistance training like yoga, pilates, or using weights. In addition, numerous studies have also shown that keeping physically active through the years can help reduce the effects of age-related weight gain. For example, one study published in the Journal of the American Medical Association found that women who were physically active in their younger years, and continued to stay active, put on less weight overall compared to their less active counterparts. Yes, exercise obviously burns calories, but it also helps keep your metabolism running smoothly and helps prevent it from slowing down, which is a big deal if you like the amount of food you're currently eating and you're able to maintain a healthy weight.
Another thing you can do is to be sure to eat regular meals and snacks, 5-6 times a day. Using money as an analogy, it's better to 'spend' your calorie budget in smaller amounts, spread evenly throughout the day rather than 'splurging' only 2-3 times a day. Small, frequent meals keep your metabolism actively working throughout the day and also help ensure you don't get too hungry and over-eat.
So that's it folks, you've heard it before, but I'll say it again - if you don't use it, you lose it, and this certainly applies to your metabolism.