Even if you are the most independent exerciser around, give a group fitness class a shot at least once a week—you may find that you enjoy it more than sweating solo. “Happiness and health are shared through social connectedness and closeness,” says Greg Chertok, director of sport psychology at the Physical Medicine and Rehabilitation Center in New Jersey. “Geography and proximity are predictors of how contagious emotions can be, and this may translate into an athletic environment too.” Sign up for Bikram, CrossFit, spin, or Zumba, and you could find yourself—gasp!—smiling at the gym thanks to your classmates.
When layering for an outdoor activity this winter, consider a compression fabric for your base layers. “These fabrics are fantastic at wicking moisture from the body, which allows you to sweat and breath while keeping you warm,” says Chiplin, who notes they can also reduce fatigue and muscle soreness so you’re ready to head out again tomorrow. Consider throwing them in the dryer for a minute before dressing to further chase away the morning chill. 
After 40, your hormone levels (estrogen) drop. This causes your insulin (hormone that helps your body use sugar) rise. Your thyroid levels go down. This combination makes you hungrier. You end up eating more and burning fewer calories. Much of the weight gain occurs around your belly. Eat more foods with fiber (berries, whole grains, nuts) to fill you up and help you eat less. Aim for 25 grams of fiber each day after the age of 40. Other ways to increase your metabolism include:
Fluids: Fluid needs increase as women age. The reason: Kidneys become less efficient at removing toxins. “Drinking more fluids helps kidneys do their job,” Schwartz says. “Unfortunately, thirst signals often become impaired with age, so people are less likely to drink enough water and other fluids.” Rather than fret about how many glasses to drink, Frechman says, check the color of your urine. "It should be clear or very pale colored. If it becomes darker, you need more fluid.”
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