CHAPTER 26 - Nutritional Guidelines and Energy Needs for the Female Athlete-Determining Energy and Nutritional Needs to Ameliorate Functional Amenorrhea.

CHAPTER 26 - Nutritional Guidelines and Energy Needs for the Female Athlete-Determining

Energy and Nutritional Needs to Ameliorate Functional Amenorrhea Caused by Energy

Imbalance

Jacalyn J. Robert-McComb, PhDFellow of the American College of Sports

Medicine

Learning Objectives

• Describe the energy availability hypothesis Describe the energy availability hypothesis and functional amenorrhea;and functional amenorrhea;

• Describe the energy and nutritional intake Describe the energy and nutritional intake estimations;estimations;

• Describe nutritional guidelines for the Describe nutritional guidelines for the female athlete; andfemale athlete; and

• Describe the importance of hydration Describe the importance of hydration before, during, and after exercise.before, during, and after exercise.

Energy Drain and Menstrual Dysfunction• The prevalence of amenorrhea is elevated in The prevalence of amenorrhea is elevated in

women who restrict their diets and are women who restrict their diets and are intensely physically active (Torstveit & intensely physically active (Torstveit & Sundgot-Borgen, 2004). Sundgot-Borgen, 2004).

• Warren was the first to suggest that Warren was the first to suggest that menstrual disorders in female athletes are menstrual disorders in female athletes are disrupted by an energy drain disrupted by an energy drain (Warren, 1980).(Warren, 1980).

Disruption of Gonadotropin Releasing Hormone (GnRH)• Winterer et al. (1984) proposed the Winterer et al. (1984) proposed the

hypothesis that failure to provide sufficient hypothesis that failure to provide sufficient metabolic fuels to meet the energy metabolic fuels to meet the energy requirements of the brain causes an requirements of the brain causes an alteration in brain function that disrupts the alteration in brain function that disrupts the Gonadotropin releasing hormone (GnRH) Gonadotropin releasing hormone (GnRH) pulse mechanism. pulse mechanism.

Reproductive Function

• Reproductive function critically depends on Reproductive function critically depends on the pulsatile release of GnRH from GnRH the pulsatile release of GnRH from GnRH neurons in the arcuate nucleus of the neurons in the arcuate nucleus of the hypothalamus and on the consequent hypothalamus and on the consequent pulsatile release of lutenizing hormone pulsatile release of lutenizing hormone (LH) from the pituitary (Loucks & Thuma, (LH) from the pituitary (Loucks & Thuma, 2003). 2003).

HypothalamusGnRh

PituitaryFSH LH

OvariesEstrogen Progesterone

Normal Menstrual CyclingFollicular Phase Luteal Phase

(around 14 days) (around14 days)Ovulation -LH Surge (around day 14)

Suppression of LH

• In the athletic female, energy drain can occur by In the athletic female, energy drain can occur by either not taking in enough calories to meet the either not taking in enough calories to meet the metabolic needs of the body or by over exercising metabolic needs of the body or by over exercising and not compensating for the energy cost of the and not compensating for the energy cost of the exercise by taking in additional calories. Hence exercise by taking in additional calories. Hence LH pulsatility can be suppressed by a combination LH pulsatility can be suppressed by a combination of strenuous exercise and caloric restriction of strenuous exercise and caloric restriction (Loucks et al., 1998) if energy availability falls (Loucks et al., 1998) if energy availability falls below a critical threshold. below a critical threshold.

Functional Amenorrhea

• This has been termed "functional amenorrhea", This has been termed "functional amenorrhea", because the problem is a functional problem because the problem is a functional problem (altered hormonal patterns), rather than an (altered hormonal patterns), rather than an anatomical problem (Loucks & Thuma, 1984). anatomical problem (Loucks & Thuma, 1984). The restoration of normal menstrual cycling has The restoration of normal menstrual cycling has been demonstrated to reoccur when the been demonstrated to reoccur when the individual's threshold for energy availability is individual's threshold for energy availability is sequentially met (Locks & Callister, 1993). sequentially met (Locks & Callister, 1993).

Threshold of Energy Availability

• Loucks and Thuma (2003) found that LH Loucks and Thuma (2003) found that LH pulsatility was disrupted abruptly at a threshold of pulsatility was disrupted abruptly at a threshold of energy availability not higher than 30 kcal/kg energy availability not higher than 30 kcal/kg LBMLBM..d in regularly menstruating, habitually d in regularly menstruating, habitually sedentary young women of normal body sedentary young women of normal body composition. composition.

• They also found that the disruptive effects of sub They also found that the disruptive effects of sub threshold energy availability were bimodal, with threshold energy availability were bimodal, with substantially larger effects occurring in subjects substantially larger effects occurring in subjects with the shortest luteal phases. with the shortest luteal phases.

Loucks and Thuma (2003)

• Not all females have the same threshold for Not all females have the same threshold for energy- availability; but if this threshold energy- availability; but if this threshold falls below a critical threshold, hormonal falls below a critical threshold, hormonal alterations will result. alterations will result.

• The restoration of normal menstrual cycling The restoration of normal menstrual cycling has been demonstrated to reoccur when the has been demonstrated to reoccur when the individual's threshold for energy availability individual's threshold for energy availability is sequentially met. is sequentially met.

Estimating Energy and Nutritional Intake• Studies consistently show that female athletes are Studies consistently show that female athletes are

not consuming enough energy to support their not consuming enough energy to support their activity levels (Pate et al., 1990). activity levels (Pate et al., 1990).

• Research with elite female swimmers, using the Research with elite female swimmers, using the doubly labeled water technique, noted that total doubly labeled water technique, noted that total daily energy increased to 5, 593 kcal daily during daily energy increased to 5, 593 kcal daily during high-volume training. high-volume training.

• However their intake averaged only 3,136 kcal, However their intake averaged only 3,136 kcal, implying a negative energy balance (Trappe, implying a negative energy balance (Trappe, 1997) 1997)

Estimated Calorie Requirements (in Kilocalories) for Specific Age Groups at Three Levels of Physical Activitya using the Institute of Medicine Equations

    Activity Levelb,c,d

Gender Age (years)

Sedentaryb Moderately Activec

Actived

Child 2-3  1,000 1,000 - 1,400e 1,000 - 1,400e

Female 4-8 1,200 1,400 - 1,600 1,400 - 1,800

  9-13 1,600 1,600 - 2,000 1,800 - 2,000

  14-18 1,800 2,200 2,400

  19-30 2,000 2,000 - 2,200 2,400

  31-50 1,800 2,000 2,200

  51+ 1,600 1,800 2,000 - 2,200

Activity Levels

• Sedentary means a lifestyle that includes only the light Sedentary means a lifestyle that includes only the light physical activity associated with typical day-to-day life.physical activity associated with typical day-to-day life.

• Moderately active means a lifestyle that includes Moderately active means a lifestyle that includes physical activity equivalent to walking about 1.5 to 3 physical activity equivalent to walking about 1.5 to 3 miles per day at 3 to 4 miles per hour, in addition to the miles per day at 3 to 4 miles per hour, in addition to the light physical activity associated with typical day-to-light physical activity associated with typical day-to-day life.day life.

• Active means a lifestyle that includes physical activity Active means a lifestyle that includes physical activity equivalent to walking more than 3 miles per day at 3 to equivalent to walking more than 3 miles per day at 3 to 4 miles per hour, in addition to the light physical 4 miles per hour, in addition to the light physical activity associated with typical day-to-day life.activity associated with typical day-to-day life.

Example of Specific Recommendations for Physically Active Females from 19-30 years from the US Department of Health and Human Services based on 2,400 calorie pattern.

Food GroupGrainsVegetables

Daily amount8 ounces3 cups

Fruits 2 cups

Milk 3 cups

Meat & Beans 6.5 ouncesOils and Discretionary Calories Aim for 7 teaspoons of oils a day

Recommendations for Macronutrients and Energy Intake for the Physically Active Female

• The Food Guide Pyramid provides broad The Food Guide Pyramid provides broad recommendations for healthful nutrition for the recommendations for healthful nutrition for the physically active individual. physically active individual.

• Diets should emphasize fruits and vegetables, Diets should emphasize fruits and vegetables, cereals and whole grains, nonfat and low-fat dairy cereals and whole grains, nonfat and low-fat dairy products, legumes, nuts, fish, poultry, and lean products, legumes, nuts, fish, poultry, and lean meats. meats.

• Female athlete’s diet have been found to be low Female athlete’s diet have been found to be low on iron, calcium, zinc, vitamin B6, and folate.on iron, calcium, zinc, vitamin B6, and folate.

Continued• Good sources of folate include fortified Good sources of folate include fortified

breakfast cereal, soy flour, beans, wheat breakfast cereal, soy flour, beans, wheat germ, chicken and beef liver, papaya germ, chicken and beef liver, papaya (see (see http://www.swedish.org/15374.cfm)http://www.swedish.org/15374.cfm)

• Studies consistently show that female athletes are Studies consistently show that female athletes are not consuming enough energy to support their not consuming enough energy to support their activity levels. activity levels.

• Low energy and nutrient intake places athletes at Low energy and nutrient intake places athletes at greater risk for nutrition related disorders such as greater risk for nutrition related disorders such as amenorrhea, osteoporosis, iron deficiency anemia, amenorrhea, osteoporosis, iron deficiency anemia, and eating disorders. and eating disorders.

Fat Intake• Fat intake should not be restricted provided Fat intake should not be restricted provided

that the fat intake is low in saturated fats that the fat intake is low in saturated fats and trans fats;and trans fats;

• There is no benefit in consuming a diet with There is no benefit in consuming a diet with less than 15% of energy from fat as less than 15% of energy from fat as compared to 20-25%. compared to 20-25%.

• Acceptable lipid intakes for physically Acceptable lipid intakes for physically active individuals ranges from 20 and 35% active individuals ranges from 20 and 35% of caloric intake. of caloric intake.

Carbohydrate Intake

• General recommendations for General recommendations for carbohydrates range between 6-10g/ kg of carbohydrates range between 6-10g/ kg of body mass per day. body mass per day.

• This range represents approximately 55-This range represents approximately 55-65% carbohydrate intake. 65% carbohydrate intake.

• Carbohydrates should be predominantly Carbohydrates should be predominantly starches from fiber-rich, unprocessed starches from fiber-rich, unprocessed grains, fruits and vegetables. grains, fruits and vegetables.

Protein Requirements• Protein requirements are slightly increased Protein requirements are slightly increased

in highly active people. in highly active people. • Protein requirements for endurance athletes Protein requirements for endurance athletes

are 1.2-1.4 g/kg body mass per day, are 1.2-1.4 g/kg body mass per day, whereas those for resistance and strength whereas those for resistance and strength trained athletes may be as high as 1.6 to 1.7 trained athletes may be as high as 1.6 to 1.7 g/kg of body weight per day. g/kg of body weight per day.

• According to the Dietary Reference Intakes, According to the Dietary Reference Intakes, acceptable macronutrient distribution acceptable macronutrient distribution ranges of protein for adults are 10-35%.ranges of protein for adults are 10-35%.

The Importance of Hydration Before, During, and after Exercise

• ACSM (1996) and NATA (Casa et al., 2000) recommend ACSM (1996) and NATA (Casa et al., 2000) recommend drinking 400-600 mL (16 to 24 oz) of fluid 2-3 h before drinking 400-600 mL (16 to 24 oz) of fluid 2-3 h before the exercise. the exercise.

• During exercise, optimal hydration can be facilitated by During exercise, optimal hydration can be facilitated by drinking 150-350 mL (6 to 12 0z) of fluid at 15-20-min drinking 150-350 mL (6 to 12 0z) of fluid at 15-20-min intervals, beginning at the start of the exercise. intervals, beginning at the start of the exercise.

• Consuming up to 150% of the weight lost during an Consuming up to 150% of the weight lost during an exercise session may be necessary to cover loses in sweat exercise session may be necessary to cover loses in sweat and urine excretion (Shirreffs et al. , 1996).and urine excretion (Shirreffs et al. , 1996).

How Exercise Nutritionists Can Help Female Athletes Maintain Energy Balance

• Athletes should be educated about energy Athletes should be educated about energy requirements for their sport and the role of food in requirements for their sport and the role of food in fueling the body. fueling the body.

• Female athletes should be educated about the Female athletes should be educated about the Female Athletic Triad and the long term health Female Athletic Triad and the long term health consequences of inadequate energy intake. consequences of inadequate energy intake.

• Unrealistic weight and body composition goals Unrealistic weight and body composition goals should be discouraged. should be discouraged.

• Body size and composition of an athlete Body size and composition of an athlete

should be assessed for the determination of should be assessed for the determination of an appropriate weight and composition for an appropriate weight and composition for the sports in which she participates. the sports in which she participates.

• Minimum body composition for good Minimum body composition for good health for the female athlete is 12%.health for the female athlete is 12%.

• Provide the athlete with nutritionally sound Provide the athlete with nutritionally sound techniques for maintaining an appropriate techniques for maintaining an appropriate body weight and composition without the body weight and composition without the use of severe diets or nutritionally use of severe diets or nutritionally unbalanced macronutrient choices. unbalanced macronutrient choices.