"Research shows that in women, metabolism declines by an average of 2 percent per decade, starting at age 20. But here's the good news: There are simple ways you can tweak your daily routine to counterbalance this natural dip." Yep, that explains it! I have to workout so much more and be more attentive to my nutrition to not even get as great of results as I did in my 20s!!! But that won't deter me! It spurs me forward!!! Check out this article on what you can do to rev up your metabolism! "After age 30, we lose 3 to 8 percent of our muscle mass per decade, which is one of the main reasons metabolism slows. To counteract that loss, aim to do two to three 30-minute strength-training sessions a week, using moves that engage as many muscles as possible, like squats, planks, and lunges."