When it comes to creating success and longevity in endurance sports, recognizing and catering to the differences between male and female athletes is vital. Erin Sprague, Women’s Product Manager at Specialized Bicycles, sums up the importance of acknowledging the differences between men and women. “As a female, you wouldn’t dream of walking into a department store and buying an outfit in the men’s department. The same holds true when you compare it to the needs of male and female athletes.” Nutrition, apparel, and assessing the physiological differences between men and women is the same way. We certainly are not in a “one size fits all” category. After all, Superman has his cape and Wonder Woman has her magic lasso. Both possess extraordinary gifts and enviable physique when they are called to action. The difference? Their own personal powers and strengths.
Throughout the next several weeks, we’ll touch on some of these differences including physiological differences that may make one gender more prone to injury than another. We’ll discuss product design, especially as it pertains to women-specific cycling. We’ll also dig into some of the emotional and psychological differences between the sexes when it comes to training and competition.
In this installment, we’ll skim the tip of the iceberg of nutrition. Many athletes may believe that men and women have different nutritional needs, but just how different are we as it relates to caloric needs, supplements, and nutritional and health testing? I talked in-depth on these topics and more with two Registered Dietitians from Austin, Texas: Christine Marquette, RD from Marquette Nutrition and Fitness and Jess Kolko, RD of Whole Foods Market. Both provide interesting advice and perspective, especially since they are both accomplished endurance athletes as well as Registered Dietitians.
How We’re Different
Those magic years of puberty are what begin to truly distinguish the differences between males and females. Up until that point, our bodies are fairly the same, with women progressing even faster than men in some cases. But, because of the increased levels of testosterone in men after puberty, the guys genetically tend to have larger muscle mass (larger muscle fibers) and a lower body fat percentage. Blame it on the estrogen if you must. Men also genetically have a higher VO2 max. A University of New South Wales research study draws a link to the hormone estrogen – and its impact on fat storage for childbearing. “On average, women have 6 to 11 percent more body fat than men. Studies show estrogen reduces a woman’s ability to burn energy after eating, resulting in more fat being stored around the body. The likely reason is to prime women for childbearing, the review suggests”.
You can see this in the range of healthy body fat percentages between the sexes. Even if a woman is at a super lean 17% body fat percentage, for example, the male equivalent would be about 9%. I know. It hardly seems fair. Because of this, even active women need fewer calories total, and the type of calories we ingest may differ in some cases based on our individual health.
The American Council on Exercise (ACE) Recommended Body Fat Percentages can be found here.
So how do we know what’s going on inside our body?
When it comes to determining whether you are in balance or deficient of crucial nutrients and minerals that endurance athletes need for performance, the best way of knowing is testing. Both Marquette and Kolko recommend a CBC (Complete Blood Count) and CMP (Complete Metabolic Panel). These standard blood tests provide a good snapshot of your overall health. According to the Mayo Clinic, the CBC is a blood test used to detect a number of disorders including anemia, infection and leukemia. A complete CBC test will measure red and white blood cell count, hemoglobin, hematocrit, and platelets. The CMP is a panel of 14 blood tests that checks kidney and liver function, as well as electrolyte and fluid balance. Based on the results of these tests, doctors and dietitians can make recommendations on nutrition, calorie intake, hydration and supplements. It’s a good starting point to know where you’re at in your current state of health. If you’re having problems, it’s also a good snapshot to know what may be troubling you.
Iron is a mineral that is responsible for transporting oxygen from our lungs to the working muscles, which is vital to any endurance athlete. Iron deficiency can lead to chronic mental and physical fatigue, among many other issues. Women lose a lot of iron each month through menstruation, so it’s recommended that women consume higher iron levels than males.
Here are iron recommendations according to the Food and Nutrition Board, Institute of Medicine, National Academies:
- Males age 19-70+ : 8mg/day
- Females age 19-50: 18 mg/day
- Females age 50+: 8 mg/day
You can take supplements, but Kolko also recommends whole foods that provide iron including: beef, eggs, dark leafy greens, legumes, tuna, shrimp, tofu, peanut butter, brown rice and more.
Calcium and Vitamin D
Both calcium and Vitamin D are essential to maintaining our bone health. Vitamin D is a hot topic these days as researchers and experts debate on whether we should hang in the sun or over-lather with SPF 100 sunscreen. If possible, get a Vitamin D screening to assess your current levels. It’s common to assume that athletes have plenty of exposure to Vitamin D because of our outdoor training, but this isn’t always the case. Low Vitamin D levels can lead to inflammation, poor immune system function and low bone density.
Here are Vitamin D recommendations according to the Food and Nutrition Board, Institute of Medicine, National Academies:
- Males and Females age 9-70+: a minimum of 200 IU/day
My research showed varying dosage recommendations, so I chose to reference one chart for all recommendations. If you are concerned about your Vitamin D levels, please consult your primary physician or a registered dietitian. Our body does produce Vitamin D with sun exposure, but there are also foods that aid in production including foods fortified with Vitamin D, fatty fish, egg yolks and cheese.
Here are calcium recommendations according to the Food and Nutrition Board, Institute of Medicine, National Academies:
- Males age 19-50 : 1000mg/day
- Males age 51+: 1200 mg/day
- Females age 19-50: 1000 mg/day
- Females age 50+: 1200 mg/day
It’s common to think that women need more calcium than men, but according to the this chart, the daily recommendations for men and women are the same. Dairy is the common go-to for calcium, but there are also many other sources including: bok choy, sesame seeds, sardines, kale, collard greens, broccoli, almonds and more.
How much is too much?
Kolko works with many athletes and the biggest issues she sees when digging through food journals is over-consumption of poor calories, basic dehydration, and for female athletes, under-fueling.
Unfortunately, endurance training doesn’t give most athletes total impunity to eat whatever they want, even though nothing tastes better than chips and queso after a century training ride. In order to perform at your peak, you must consistently fill your body with clean fuel and proper nutrition. If you are frustrated that you’re not achieving the results that you want on the scale or in training, start to keep a food log and assess the type of calories and the amount you are consuming.
Under-Fueling for Female Athletes
According to The American College of Sports Medicine (ACSM), the Female Athlete Triad is a syndrome of three interrelated conditions that exist on a continuum of severity when a female has extremely high activity levels and extremely low body fat percentages. Often, this happens when a female athlete is competitive, if their sport emphasizes leanness for performance, or when the calorie intake doesn’t match energy expenditure. These conditions include:
- Energy Deficit/Disordered Eating
- Menstrual Disturbances/Amenorrhea
- Bone Loss/Osteoporosis
The more severe the symptoms, the more dire the consequences. As a Registered Dietitian, Kolko is one of the health care professionals who is on the front lines of recognizing these conditions. If you are suffering from any or all of the above, seek professional medical assistance. “If possible,” says Kolko, “engage a support team that may include a Dietitian, Primary Care Physician, Sports Psychologist and your OB-GYN.” The ACSM notes several warning signs of under-fueling and potential eating disorders. Among them: rapid weight loss, under-performance, fatigue, stress fractures, excessive leanness and depression. Behavioral symptoms include preoccupation with weight, food, mealtime rituals and body image; and avoidance of team or group meals or secretive eating.
Water, naturally, is vital to our overall health, joint function, organ function, fatigue levels and so much more. Both Marquette and Kolko recommend quantities near 100oz of water per day for both men and women, especially in warmer climates.
As Marquette notes, as we age, both men and women need fewer calories (even if we are active). In general, a 40-year-old athlete who is the same size and working at the same intensity as a 20-year-old will need fewer calories because of a slower metabolism and decreased amount of muscle mass. Getting old is tough, but this is also where quality of food trumps quantity. Although male and females differ in relation to size and metabolic function, our basic needs are very similar. Active women and older athletes just require fewer calories in general since our metabolism begins to hit the brakes. After age 50, Marquette also recommends that athletes eat more leafy greens and other sources of calcium, consume more Omega 3s (walnuts, flax, chia and hemp) to help combat inflammation and speed recovery, and stay on top of hydration to increase flexibility and decrease risk of injury.
Kolko agrees with quality over quantity, even during racing and training. She’s an advocate for consuming real food during training (if you can tolerate it) because the water content in the food is greater than any processed food product. You don’t need as much protein during training and racing because your body is better at burning fats and carbs. Protein is more important during recovery or post-race. Some real food suggestions include: small boiled potatoes with salt, sticky rice balls, almond butter on bread and even bars that are made of real food including peanuts, salt and dates.
The bottom line? In most cases, the nutrition needs of men and women are surprisingly similar and it boils down to a solid nutrition plan that includes real whole foods. A diet that is high in whole, unprocessed foods provides both male and female athletes an insurance policy against many illnesses and deficiencies that come as a result of a lack of proper vitamins, minerals and caloric intake. Both require essentially the same levels of Vitamin D and Calcium, though women require more Iron prior to menopause. Women should be careful of under-fueling but both sexes should be sure they are consuming quality calories. A sound diet and training regime will also promote proper body fat percentages and the best scenario for peak performance.
Are men from Mars and women from Venus? Who knows. With the right nutrition strategy a strong athlete, regardless of sex, can produce results and powers that are truly out of this world.