When you do high-intensity interval training (and if you’re not, you should be!), follow a 2:1 work-to-rest ratio, such as sprinting one minute followed by 30 seconds of recovery. [Tweet this secret!] According to several studies, the most recent out of Bowling Green State University, this formula maximizes your workout results. The BGSU researchers also say to trust your body: Participants in the study set their pace for both running and recovery according to how they felt, and by doing so women worked at a higher percentage of their maximum heart rate and maximum oxygen consumption than the men did.
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.”
Having the proper footwear is essential for any workout, and for winter runs, that means sneaks with EVA (ethylene vinyl acetate), says Polly de Mille, an exercise physiologist who oversees New York Road Runner's Learning Series for first-time New York City Marathon runners. “Polyurethane tends to get really stiff and cold in the winter, which could increase your risk of injury.” Another important feature is a waterproof and windproof upper: Look for shoes made with Gortex, or wrap your mesh uppers in duct tape to keep feet dry and warm.

The average woman should get 10 to 35 percent of her daily calories from protein. Protein helps prevent muscle tissue from breaking down and repairs body tissues. Sources of animal proteins include meat, fish, poultry, eggs, milk and cheese. Vegetable proteins include dried beans and peas, peanut butter, nuts, bread and cereal. (A three-ounce serving of cooked chicken contains about 21 grams of protein.)

Folate or vitamin B9 (also known as folic acid when used in fortified foods or taken as a supplement) is another nutrient that many women don’t get enough of in their diets. Folate can greatly reduce the chance of neurological birth defects when taken before conception and during the first few weeks of pregnancy. Folate can also lower a woman’s risk for heart disease and certain types of cancer, so even if you’re not planning on getting pregnant (and many pregnancies are unplanned), it’s an essential nutrient for every woman of childbearing age. In later life, folate can help your body manufacture estrogen during menopause.

The recommended daily intake for vitamin E is 15 mg. Don't take more than 1,000 mg of alpha-tocopherol per day. This amount is equivalent to approximately 1,500 IU of "d-alpha-tocopherol," sometimes labeled as "natural source" vitamin E, or 1,100 IU of "dl-alpha-tocopherol," a synthetic form of vitamin E. Consuming more than this could increase your risk of bleeding because vitamin E can act as an anticoagulant (blood thinner).