Calcium: “Getting enough calcium is important for all ages, but it's particularly important during adolescence and early adulthood, when bones are absorbing calcium,” says Heather Schwartz, MS, RD, a medical nutrition therapist at Stanford University Hospital and Clinics. Calcium and vitamin D are often paired in fortified foods such as milk. The reason: The body needs D in order to absorb calcium.
Research has consistently shown that the elliptical, although easiest on joints, is worse than the treadmill, stationary bicycle, and rowing machine (not to mention activities such as swimming and intense hiking) when it comes to elevating heart rate and burning body fat. This is due to the fact that movement on these machines relies heavily on momentum and not resistance or the propelling of one's bodyweight. All these months of elliptical training has yielded mediocre results, and now you know why.
Instinct may tell you to slow down when running in wintery conditions, but the secret to not slipping is actually to speed up and shorten your stride. Aim to have each foot strike the ground 90 times per minute, says Terry Chiplin, owner of Active at Altitude, a Colorado-based facility for endurance athletes. This high cadence helps ensure that each foot lands beneath the center of your weight rather than ahead of it, which can throw off your balance on slick terrain. 
In the past, women have often tried to make up deficits in their diet though the use of vitamins and supplements. However, while supplements can be a useful safeguard against occasional nutrient shortfalls, they can’t compensate for an unbalanced or unhealthy diet. To ensure you get all the nutrients you need from the food you eat, try to aim for a diet rich in fruit, vegetables, quality protein, healthy fats, and low in processed, fried, and sugary foods.