Empowering Female Athletes

This blog is directed towards the nutrition of female athletes. Sports nutrition research has primarily revolved around male athletes, neglecting the distinct physiological and hormonal variances in females. It is important to recognize that data derived from male athletes has been extrapolated to female athletes without a thorough evaluation of its relevance.  

Information is Key

Women looking to improve training and nutrition, a vital starting point is self awareness. Female athletes have unique and unpredictable hormone profiles that affect their bodies and nutrition needs at various stages in life. Women in reproductive years should keep track of their hormonal changes related to training and recovery to understand their individual patterns and needs. Once determining what your personal patterns are and how they impact your hormone profile, you can then customise strategies that suit your body and your sport's requirements. 

Are you Eating Enough?

When talking Nutrition, the first and most crucial need for all athletes, regardless of age, hormonal profile, or sport, is ensuring you are consuming enough energy to meet all of life's demands. According to Dr Stacy Sims there's a growing concern about Low Energy Availability (LEA) among athletes at all levels, it is essential to grasp what is contributing to LA in sports and what the consequences are. Currently, there are no firmly established scientific guidelines for optimal energy intake for female athletes. However, models indicate that energy needs are likely to vary between training days. Timing your nutrient intake is crucial, to ensure that you're eating enough to match the energy used whilst training, ultimately preventing low energy. Athletes benefit from eating around their training load as it helps their bodies adapt better and reduces the increase in cortisol and epinephrine, which can acutely harm the immune system. 

Taking into account the hormonal shifts in naturally cycling women, they require slightly more energy (150 - 300 calories/day) and increased protein intake (12%) during the luteal phase to meet the additional demands for their endometrial lining. Women on hormonal birth control should be careful about their calorie intake and recognize signs of low energy. Contraceptive use can mask changes to the menstrual cycle. For peri and postmenopausal women, it might be challenging to differentiate LE and menopause symptoms. In such cases leaning into nutrient timing and energy needs helps reduce the risk of LE. 

Identifying Carbohydrates

Athletes must eat sufficient carbohydrates to avoid Low energy. which is vital as carbs are often criticized by the media. Sex differences and hormones affect how women use carbs and fats for energy. Women are quite adaptable metabolically, but they still need carbs to burn fat during exercise. So, the experts recommend that female athletes eat enough carbs throughout their menstrual cycle according to their training needs. 

Additionally, it is advised to increase carbohydrate intake during active pill weeks for oral contraceptive users and during the luteal phase of the menstrual cycle. This helps offset hormonal effects that can lower glycogen and glucose levels during exercise. A realistic starting point is to eat 30 to 60 grams of carbs per hour during exercise lasting 90 minutes or longer. This helps offset the menstrual cycle's effects on glucose metabolism and lower the risk of Glyometic Index discomfort.  Immune problems, and protein breakdown. 

For those experiencing GI issues, keep track of your menstrual cycles and hormone status to identify phases when problems are more likely. Also, monitor if your carb intake affects these symptoms. If GI distress is an issue, start with 30 grams of carbs per hour and don't go beyond 6- grams per hour. In terms of recovery, it's vital to refill your glycogen (energy) stores within 24 hours after intense workouts to boost your performance and overall well-being. 

It is recommended female athletes focus on rapid consumption of at least 1.3 grams of carbohydrate per kilogram of body weight (0.54 grams of carbohydrate per pound of body weight), after exercise to replenish muscle glycogen. Women in peri and post-menopause can benefit from using the initial 30 to 40-minute phase of glycogen synthesis, which doesn't rely on insulin after a prolonged glycogen-depleting exercise session. 

The Protein Perspective

Lets start with the basics: The current protein recommendation for women is 0.8 grams per kilogram of body weight. They derived this recommendation using nitrogen balance studies. Nitrogen is crucial for bodies, and we get it mainly from the amino acids in proteins. The idea behind nitrogen is simple: if you consume more nitrogen (protein) than you lose your in a nitrogen balance, which is good for building body proteins. If you lose more nitrogen than you take in, you're in a negative nitrogen balance, which means you're breaking down more body proteins than you're replacing. 

Nitrogen balance studies are useful for preventing malnutrition but not for determining the ideal protein intake for athletes. Athletes especially females, may struggle to maintain a positive energy balance due to high training demands and sometime restricting calories. In such cases, higher protein intake is vital for preserving muscle and performance. 

Inadequate amino acids before and after exercise will lead to muscle loss and slower recovery. Athletes should ensure they consume enough protein and time it correctly to support muscle growth, maintain a positive nitrogen balance, and prevent muscle breakdown. 

What about the Window?

Post Exercise nutrition has two main goals: replenish glycogen and prevent muscle protein breakdown. When you eat protein, your body becomes more anabolic for about 3 hours, which stops muscle protein breakdown. 

Women return to baseline much faster and their protein requirements vary depending on their hormonal status. During the luteal phase, females need more lysine, but they have a lower capacity to absorb and use amino acids for protein synthesis compared to the follicular phase. Women using oral contraceptives have a different amino acid profile in their blood compared to naturally cycling women and this is influenced by the type of progestin in the contraception. Peri and post-menopausal women become more resistant to muscle protein building due to changes in their response to exercise and amino acid uptake. 

In summary, this position stand was aimed to compile research- based guidelines for women. These guidelines may change as new science emerges.