Sports, Exercise and Nutrition Flashcards

Sports and Exercise Nutrition

• Focus of sports nutrition.

Learning Objectives

• Define fitness and its components.

• Describe the benefits of exercise and physical activity.

• List the 3 energy systems used by the body.

• Explain energy system usage during low, moderate, and high-intensity exercise.

• Describe REDS and associated health consequences.

• Summarize general recommendations for fluid, protein, and carbohydrate intake for athletes.

Benefits of Exercise

• Helps prevent chronic diseases (increases HDL, decreases resting heart rate, decreases heart pressure).

• Helps with stress management.

• Improves sleep quality.

• Helps with body weight management.

• Maintenance of muscle mass.

Body Weight Management

• Exercise assists with weight management by:

  • Regulating hunger.

  • Increasing the metabolic rate (with the increase in muscle mass vs fat mass).

• In older adults, exercise is also important for maintaining strength, improving balance, and recovery from illness.

Exercise Recommendations

• According to the American College of Sports Medicine, adults should:

  • Do at least 30 minutes of moderate aerobic activity 5 days a week OR vigorous aerobic activity 20 minutes for 3 days a week.

• Components of fitness:

  • Cardiorespiratory endurance.

  • Muscular strength.

  • Muscular endurance.

  • Flexibility.

Exercise Intensity

• Exercise intensity is important as it will determine how your body responds to the exercise.

• Intensity is broken down as:

  • Light: <55% max heart rate

  • Moderate: 55-70% max heart rate

  • Vigorous: 70-85% max heart rate

• What is your max heart rate?

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Strength Training Recommendations

According to the American College of Sports Medicine:

• 8-10 multi-joint exercises that stress all major muscle groups

• 2-3 sets of 8-10 reps for each exercise

• Controlled movements

• Close to failure for the last rep of an exercise

• Strength train 2-3 times per week

• Progressively increase weight amount

• Benefits

  • Reduce chronic disease risk

  • Improve bone density

  • Improve overall health

  • Reduce injury and frailty

  • Enhance performance

  • Improve body composition

Stretching Recommendations

According to the American College of Sports Medicine:

• Static stretching: Holding for 10-30 seconds

• Dynamic stretching: slowly working a muscle through a range of motion actively, not holding.

  • Good for warming up before exercise

• Target each major muscle tendon unit

• At least 2-3 times per week

• Daily can be effective

• Stretch to slight discomfort

• Benefits

  • Increase flexibility to prevent injury

  • Reduce inflammation

  • Improve range of motion

  • Allow freedom of movement

  • Help with relaxation and relief

Sport and Exercise Nutrition

• Nutrition recommendations depend on:

  • Training level

  • Training frequency

  • Training duration

  • Goals

  • Personal and Athletic History

  • And other factors

Training Level

• Training level will dictate many of the nutrition interventions that we can have for an athlete.

• A variety of people look for sports nutrition support from hobby athletes to professional athletes and everything in between.

  • BCS Soccer League

    • Population: Older than 18, middle-aged adults

    • Training: Little to no training for soccer outside of playing

    • Goals and Needs: Maintain health and safety when playing. Support performance of casual games

    • Resources: May have disposable income but soccer is a hobby

    • Outside Factors: Work full time and may have family responsibilities

  • Texas A&M Varsity/ Club Team

    • Population: College aged players

    • Training: Training a few days a week

    • Goals and Needs: Increase
      performance and fitness, improve recovery and body composition

    • Resources: May have university services but limited access and funding especially if club team

    • Outside Factors: Balance being a student athlete with small chance of continuing to professional athlete

  • Real Madrid Club de Futbol

    • Population: Players from teenagers to mid 30’s generally

    • Training: Training every day with multiple workouts or sessions in a day

    • Goals and Needs: Tailoring nutrition for individual needs for performance, recovery, injury prevention, and periodization of nutrition plans

    • Resources: Full access with support staff of chefs, dietitians, trainers, etc. Can get custom individualized plans for needs

    • Outside Factors: May have some family demands but soccer is their career and focus.

Training Intensity and Duration

• Intensity:

  • %VO2 max is the percent of your maximum effort

  • The higher your work effort:

    • The more energy you expend

    • The more you rely on carbohydrates

• Duration:

  • The longer you workout:

    • The more energy you expend

    • The more you rely on fat

Anaerobic vs Aerobic

• All movement uses ATP

• ATP must be resynthesized from one of these three sources.

  • Creatine Phosphate

  • Anaerobic metabolism

  • Aerobic metabolism

Anaerobic Metabolism: ATP- Phosphocreatine System

• Immediate source of energy for the body

• Lasts 10-30 seconds

• Uses stores of Phosphocreatine

• Anaerobic (does not require oxygen)

Anaerobic Metabolism: Glycolysis

• Used during the first 2-3 mins of activity

• Breakdown of glucose (from glycogen) to pyruvate.

• Pyruvate gets converted to lactic acid.

• Much of that lactic acid is transported to the liver

• 2 lactic acid molecules will get converted to glucose.

• The process of transporting lactic acid from muscle to liver and return of glucose to muscle is the: Cori Cycle

Aerobic Metabolism

• Meets prolonged demands of sustained activity:

  • 2 mins to several hours

  • Carbohydrates, fat, and amino acids are continuously oxidized to provide ATP.

• During rest, the body derives most ATP from the oxidation of:

  • Fatty acids and glucose.

• During Physical activity, body adjusts fuel mixture:

  • Muscles always use a combination of fuel source.

Calorie Needs For Athletes

• Regular, intense exercise can more than double the caloric requirement for athletes vs. sedentary individuals.

• Athletes and those who exercise regularly should:

  • Obtain additional calories from nutrient-dense foods:

    • Whole grains

    • Dairy (or dairy substitutes)

    • Lean protein sources

    • Fruits and vegetables

    • Unsaturated fats

  • Eat small meals/snacks every 3–4 hours to maintain energy levels.

Calorie Needs For Athletes

• Athletes participating in sports in which weight or appearance is judged often reduce calorie intake.

• Other athletes don’t understand their calorie needs and undereat

• Other athletes have unhealthy obsession with weight gain to achieve more muscular physique:

  • May use anabolic-androgenic steroids (AAS)

Relative Energy Deficiency in Sports

• REDS is a syndrome that stems from low energy availability in athletes.

• There are numerous health impacts including:

  • Impaired menstrual function

  • Impaired bone health

  • Metabolism dysregulation

  • Mental health issues

  • Cardiovascular dysfunction

  • And more

• There are numerous performance impacts as well:

  • Decreased strength

  • Decreased motivation

  • Decreased endurance performance

  • And more

Carbohydrates as Fuel

• Primary fuel source of moderate to intense exercise is carbohydrates

• Most of the carbohydrates used are in the form of glycogen

• Glycogen is the storage of carbs in the muscle and liver

• Higher intensity exercise depletes glycogen stores quicker

• After 60-90 minutes of exercise, glycogen stores will be low

• “Hitting the wall” or “bonking” results in feeling tired and weak as well as a drop in performance

Carbohydrates as Fuel: During Exercise

To extend “Hitting the wall”

• Consume high carbohydrates food and beverages before and during prolonged exercise

• Sports drinks, energy gels, and chews can all provide carbohydrates as well as electrolytes

Carbohydrates as Fuel: Daily Intake

• Daily carbohydrate needs depend on exercise frequency, intensity, and duration.

• Recommendations also use g/kg instead of percent of calories to account for differences in body weight allow for more exact recommendations based on body size.

Fat as Fuel

• Primary fuel source at rest and during low intensity exercise

• As intensity of exercise increases, the body relies more on carbohydrates and less on fats for fuel

• Fat is stored in much greater amounts than carbohydrates

• A 160lb athlete with 12% body fat will have 1,500-2,000 kcals of glycogen stores but will have closer to 90,000kcals of energy stored in fat

• Recommendations:

  • 20-35% of total Calories

Protein as Fuel

• Protein serves many roles but two that are important for athletes are:

  • Muscle building and recovery

  • Enzymes to help regulate metabolism

• Protein is not really used for energy production. It provides 5-15% of energy. Though it will be used for energy during:

  • Starvation

  • Limited carbohydrate supplies

  • In long endurance events without carbohydrate intake, protein breakdown may increase to provide energy but following sports nutrition guidelines reduces this need

Protein Requirements

• General recommendations for athletes is 1.2-2.0g/kg depending on goals and energy intake

• Both strength and endurance athletes have higher needs than sedentary people

• Strength athletes need 1.6-1.7g/kg protein for:

  • Muscle repair

  • Muscle growth

• Endurance athletes need 1.2-1.7g/kg protein for:

  • Muscle repair

  • Exercise adaptations

  • Energy needs

• Protein supplementation is not required

Pre-Exercise Eating

• People training for more than 1 hour may benefit from eating a snack or meal before exercise higher in simple carbohydrates

• For 90 minute or longer events, athletes may increase carbohydrate the days leading into the event to increase glycogen stores and improve endurance

Nutrition During Exercise

• Carbohydrates

  • When exercising at higher intensities and for longer than 45 minutes to an hour, consuming 25-30g of carbs can help performance

  • Longer training sessions or events may need more carbohydrates, up to 90g/hr.

• Fluids and Electrolytes

  • For shorter training sessions, fluid intake should be about 7-10 ounces every 10-20 minutes.

  • For sessions longer than 2 hours, an athlete may benefit from adding sodium depending on heat, humidity, fluid consumption, fitness, and other factors.

Nutrition After Exercise

The goals after exercise are the four R’s: rehydrate, refuel, repair, and rest. This begins within the first two hours after exercise.

• Rehydrate: consume 1.5x the amount of fluid lost during exercise. To figure this out, weight yourself before and after exercise with minimal clothing. If you lose 1lb, then you should rehydrate with 24fl oz.

• Refuel: consume 1-1.2g of carbohydrates/kg body weight to start to refill glycogen stores.

• Repair: consume 0.5g of protein/kg body weight to help with repairing muscles.

• Rest: Making sure to get adequate sleep, 7-9 hours, and not overtraining will help improve exercise recovery and adaptations.

Monitoring Hydration

• The urine color chart is a validated way to monitor hydration

• You want your urine to be a light lemonade color

• If your urine is clear, then you may be over- hydrated

• Drinking a large water bottle quickly may cause a change to a lighter color, but it will be a temporary change. Your body will urinate out the sudden increase in water and will not hydrate your cells.

Nutrition for Pregnancy, Breastfeeding, and Infant Feeding

LEARNING OBJECTIVES

1. Identify nutrient needs and recommendations during pregnancy for: energy, protein, carbohydrates, fat, folate, vitamin B12, iron, calcium, zinc, and fluid.

2. Discuss the need for supplementation during pregnancy and who would benefit most from supplementation.

3. Describe the following complications of pregnancy: gestational diabetes, edema, pre-eclampsia, eclampsia.

4. List the gastrointestinal complications associated with pregnancy and reasons for these complications.

5. Identify the negative impact of the following during pregnancy: caffeine, alcohol, smoking.

6. Identify food-borne illnesses of greatest concern during pregnancy.

7. List the benefits of breastfeeding for the mother and infant.

8. Compare the composition of colostrum vs. mature breast milk.

9. Identify recommendations for infancy in early foods.

STAGES OF PREGNANCY

• Full-term pregnancy lasts for 38-42 weeks

• Divided into three stages of about 13 weeks each

  • Trimesters

• Stages mark different phases of fetal development

  • associated with different health implications and physical sensations for woman

COMPOSITION OF MATERNAL WEIGHT GAIN DURING PREGNANCY

• Baby: 7.5 lb

• Amniotic fluid: 2 lb

• Placenta: 1.5 lb

• Uterus: 2 lb

• Breasts: 2 lb

• Body fluids: 4 lb

• Blood: 4 lb

• Maternal stores of fat, protein, and other nutrients: 7 lb

LOW-BIRTHWEIGHT NEWBORNS

• Undernourished women likely to give birth to smaller baby.

• Infant <5.5 lb. is considered:

  • Low birth weight

  • At risk for:

    • infection

    • lung problems

    • learning disabilities

    • increased mortality

WEIGHT GAIN DURING PREGNANCY

MEETING INCREASED NUTRIENT NEEDS

Nutritional needs increase during pregnancy

• Should be met by eating nutrient-dense foods

• Calorie needs:

  • No increase during the first trimester

  • After the first trimester

    • Increase 200-300 calories/day from pre-pregnant calorie requirements

  • Best indicators that energy needs are being met:

    • Hunger

    • Progression of weight gain

PROTEIN REQUIREMENTS DURING PREGNANCY

Protein is important for building body tissues. Protein needs during pregnancy increase by ~25 g per day

• Sources of protein:

  • Lean meats, poultry, dairy, legumes

  • Fish (avoid predatory fish: king mackerel, tilefish, swordfish – mercury content)

  • Tofu, legumes, nuts, and grains can supply adequate protein

• Vegetarians need to pay close attention to protein intake.

CARBOHYDRATE REQUIREMENTS DURING PREGNANCY

Carbohydrates are the primary source of energy for pregnant females. A pregnant woman should consume ≥175 g carbohydrates per day

• Fiber

  • Helps prevent constipation and hemorrhoids

• Decrease intake of simple sugars or empty calories in order to meet the increased nutrient needs

FAT REQUIREMENTS DURING PREGNANCY

Recommended total fat intake does not change during pregnancy. Fats are a source of energy

• During the 3rd trimester, fetus stores fat as energy to use as a newborn

  • Increase essential fatty acids intake

  • Linoleic and alpha-linolenic acid

  • Focus on polyunsaturated fats found in nuts, oils, and whole grains

VITAMIN AND MINERAL REQUIREMENTS DURING PREGNANCY

FOLATE REQUIREMENTS

• Inadequate folate/folic acid during pregnancy:

  • Neural tube defects

    • Spina bifida

    • Anencephaly

  • Also, preterm delivery, low- birthweight baby, and slow fetal growth rate.

• RDA:

  • 600 µg a day

  • Also applies to women planning to become pregnant

IRON REQUIREMENTS

RDA for iron increases

• 27 mg per day

• Pregnant woman is no longer losing blood and iron through menstruation, but increases iron intake is required for:

  • building red blood cells in the fetus to carry oxygen to cells

• Maternal iron-deficiency anemia associated with an increased risk of:

  • Premature delivery

  • Low birthweight

  • Low iron stores in the infant

CALCIUM REQUIREMENTS

Calcium is needed for:

• development of bones and teeth in the fetus

• maintain strength in the bones of the mother

• RDA for calcium does not increase during pregnancy

  • Absorption doubles in intestines

  • The kidneys increase resorption

  • Calcium turnover in bone increase

• Calcium needs increase as much as 30 mg/day during the 3rd trimester

ZINC REQUIREMENTS

Zinc requirements increase by more than 30% during pregnancy

• Needed for DNA and RNA syntheses

• Inadequate zinc intake during pregnancy can lead to:

  • birth defects

  • poor cognitive development after birth

  • premature delivery

  • prolonged labor

PRENATAL VITAMIN AND MINERAL SUPPLEMENTS

• Supplementation of some nutrients is recommended:

  • Iron

    • Needs difficult to meet via diet

  • Folic acid

    • Should begin 1 month before conception

  • Calcium

    • Recommended for vegans, women <25 yrs. of age, and those avoiding milk products

SUPPLEMENTS AND NUTRITIONAL RISK

• Multi-vitamin/mineral supplement recommended for women at nutritional risk:

  • Vegans

  • Breast-feeding women

  • Follow restrictive diets

  • Smoke cigarettes

  • Abuse alcohol

  • Are carrying twins or triplets

HYDRATION

• General fluid needs increase during pregnancy in order to support fetal circulation, amniotic fluid, and higher blood volume

  • May also help prevent constipation

• Recommended Intake:

  • 1-1.5 mL of water per calorie consumed

  • Pregnant women advised to increase caloric consumption by 300 calories beginning in the second trimester

    • Increase fluid by 300 mL above non-pregnancy intake

FOOD CRAVINGS

Specific food cravings are typically harmless during pregnancy. Cravings leading to the consumption of non-food substances can be harmful.

• Pica

  • Compulsive eating of nonfood substances, such as clay, chalk, or dirt

  • Pica can lead to:

    • iron deficiency in the mother

    • smaller head circumference in the infant

    • inadequate weight gain

    • Other complications: intestinal blockages, diarrhea, vomiting, infections

GASTROINTESTINAL ISSUES

Pregnancy hormones cause muscle and ligament relaxation

• Makes labor easier

• May cause constipation

• May result in the development of hemorrhoids

• Hormonal changes can also relax esophageal sphincter

  • Resulting in heartburn

    • Recommendations to prevent heartburn:

      • Eat smaller meals

      • Avoid foods that seem to cause heartburn (i.e., spicy foods and chocolate)

      • Elevate head when sleeping

      • Sleep on the left side of the body

COMPLICATIONS DURING PREGNANCY

• Fluid retention that results in swelling of hands, feet, and ankles:

  • Edema

• Rapid rise in blood pressure readings above 140 mm Hg (systolic) and 90 mm Hg (diastolic):

  • Pregnancy-Induced Hypertension

    • May advance to pre-eclampsia characterized by:

      • High blood pressure and edema

      • protein in the urine

    • Eclampsia is a manifestation of pre-eclampsia

      • Convulsions or seizures

COMPLICATIONS DURING PREGNANCY

• Rise in blood glucose diagnosed during pregnancy

  • Gestational diabetes

    • Usually controlled via diet and lifestyle

• Complications associated with exposure to increased glucose

  • For Infant:

    • Very large birth weight

    • Macrosomia

    • Low blood glucose following delivery

  • For mother:

    • increased risk for Type 2 Diabetes

CAFFEINE

• Caffeine travels through the placenta and can affect fetal heart rate and breathing.

• Consuming >2 cups of coffee daily may increase the risk of miscarriage or low- birthweight baby.

• Breast milk can also transfer caffeine to baby

  • Irritability in baby

• Recommendation:

  • Avoid or limit caffeine to ≤300 mg per day

ALCOHOL

• NONE Recommended alcohol intake during pregnancy:

• Fetal alcohol syndrome (FAS)

  • Characterized by growth retardation, facial abnormalities, and central nervous system (CNS) dysfunction

Condition in infant caused by maternal alcohol consumption:

SMOKING

May impair blood flow to developing fetus which may decrease nutrient and O2 delivery

Smoking is associated with increased risks for:

• Miscarriages

• Preterm delivery

• Smaller birth weight

FOOD-BORNE ILLNESS

• Weakened maternal immune system & immature fetal immune system

  • Harder to fight off harmful microorganisms

• Increased risk of food-borne illness during pregnancy

  • Listeria:

    • Found in:

      • Uncooked meats and vegetables and unpasteurized milk

      • Ready-to-eat foods (i.e., hot dogs and deli meats)

  • Toxoplasma:

    • Parasite found in undercooked meat

    • Cat litter

• Greatest concerns:

BREASTFEEDING

• Breast-feeding recommended as preferred method of feeding for newborns and infants

• Although exclusive breast-feeding is ideal, even some breast-feeding appears to be beneficial for mother and newborn

• Benefits of breastfeeding for the mother:

  • Lose weight faster

  • Build stronger bonds with their babies

  • Decreased risk of breast and ovarian cancer

  • Saves money by not buying formula

BENEFITS FOR NEWBORN

According to the American Academy of Pediatrics and the Academy of Nutrition and Dietetics, breast-fed newborns are less likely to experience:

• Allergies and intolerances

• Ear infections (otitis media)

• Vomiting

• Diarrhea

• Pneumonia, wheezing, and other respiratory diseases

• Meningitis

• Sudden infant death syndrome (SIDS)

• Possible reduced obesity

BREASTMILK COMPOSITION

FIRST DAYS OF LIFE

• Newborns have very small stomachs

  • Volume of initial meals is 2–20 mL

• First milk produced after birth is of thinner consistency and is slightly yellowish in color:

  • Colostrum

    • High in protein

    • Contains maternal antibodies and serves as a laxative to clear meconium

    • Frequent, small meals in first few days coat baby’s digestive tract and prevent invasion of foreign substances

BREASTFEEDING AFTER 6 MONTHS

• Slowly, solids become the main food source

• Solid foods should be offered along with breast milk after 6 months of age (along with readiness to eat cues)

• Recommendations for feeding infant:

  • Exclusively breast feed for the first 6 months

  • Continued supplemental breast-feeding for up to 1 year

  • No additional benefit to infant beyond 1 year of age

MOTHER'S NEEDS DURING BREASTFEEDING

• If exclusively breast feeding:

  • 640 calories/day above pre-pregnancy calorie requirement for the first 6 months

    • Some calories come from fat stores

    • 500 calories/day from diet for the first 6 months

    • 400 calories/day for the second 6 months

MATERNAL NUTRITIONAL NEEDS CONTINUED

• Carbohydrates

  • Requirement increase by 80 g from pre-pregnancy requirements

• Protein

  • increase by 15–20 g above pre-pregnancy requirements

• Fat

  • No more than 30–35% total calories from fat

  • At least 10% from monounsaturated and 10% from polyunsaturated sources

• Iron needs decrease during lactation

• Avoid alcohol

NUTRITIONAL NEEDS OF INFANTS BEYOND MILK (POST 6 MONTHS)

• Rapid growth during the first year:

  • Double birth weight by 4 to 6 months

  • Triple birth weight by 12 months

• High calorie needs to support rapid growth:

  • 40–50 calories per pound body weight per day

• Fat:

  • Needed for growth and development

  • 50-60% of caloric intake should come from fat

• Protein:

  • Growth

  • No more than 20% of total calories from protein

HYDRATION

Infants are at an increased risk for dehydration. Why?

• Lose more water via evaporation

• Their kidneys are not completely developed

• Infants need 1/3 cup fluid per pound of body weight (up to 18 lbs.)

  • May dilute the sodium in blood

  • May cause water intoxication

  • Can lead to seizures, coma, and death

• Not advisable to dilute formula with water

• Never give infant (< 1 year) cow’s milk, goat’s milk, or soy milk

VITAMIN AND MINERAL BEYOND MILK

• Vitamin K

  • Shots given to all babies at birth in the U.S.

• Vitamin D

  • Low in breast milk

• Iron

  • Additional iron needed for exclusively breast-fed infants at 4-6 months of age

• Fluoride

  • Breast-fed infants >6 months of age may need supplement

• B12

  • Babies breast-fed by vegan mothers may need supplement

STARTING SOLID FOODS

• American Academy of Pediatrics and WHO recommend:

  • waiting until 6 months of age to introduce anything but breast milk

• Why wait?

  • Healthy, full-term infant born with adequate iron and zinc stores.

  • Levels of these nutrients decrease in breast milk after 3 months

  • Infant’s stores used up by ~6 months

• Solids and liquids that join breast-feeding in normal progression toward adult eating patterns are known as:

  • Complementary foods

SOLIDS

• Introducing solids to infants early may lead to serious health problems.

  • Iron-fortified cereal is a starch.

  • Enzyme for digestion not produced in sufficient amount until ~6 months of age

• Introducing solids before 4 months may increase the risk of Type 1 diabetes

• Fruits and vegetables before 6 months can increase the risk of anemia

• Chunky foods can result in choking

• Can also increase the risk of obesity in later life

SOLID FOODS

• Nutrients identified as problematic for breast-fed infants after 6 months of age:

  • Iron, zinc, vitamin A, and vitamin B6

  • Nutrients not as great a concern for formula-fed babies

    • Due to fortification of formulas

• Breast-fed babies require complementary foods high in iron and zinc .

  • Iron-fortified cereals are often the first foods introduced

  • Rice cereal is least allergenic

SOLID FOODS

• Physical signs (milestones) are indicators that baby is ready for solids:

  • By 6 months of age, most babies have lost tongue- thrusting reflex, or:

    • Extrusion reflex– pushing food forward with their tongue

  • Capable of sitting on their own

  • Become intrigued with sight of spoon, fork, or cup

  • Capable of bringing item to his or her mouth, chewing, and swallowing

SEQUENCING SOLID FOODS

• Traditional recommendations regarding the order of solid food introduction are based on preventing allergies.

• Recommendations include:

  • Introducing one food at a time

  • Watch for signs of food allergies or intolerance

• Typical sequence includes:

  • Iron-fortified cereal

    • Rice cereal

  • Fruits and vegetables

  • Meats

CHOKING HAZARDS:

Avoid the following for the first few years:

• Nuts

• Whole grapes

• Popcorn

• Hot dog pieces

• Any large chunks of raw foods that must be thoroughly chewed

• Small candies

• Cherries and some dried fruits

OTHER RECOMMENDATION:

• Infants or toddlers who go to bed with a bottle