Chapter 10 Nutrition Strategies for Maximizing Performance

Weight Gain

*consume about 500 additional calories per day in order to gain weight (so don't increase too much fat) -eating larger portion sizes -increasing meal frequency -focusing on choosing calorie-dense foods -eat enough protein to maximize gains in lean body mass: 1.5-2.0 g per kg body wt per day.

2. What makes the GREATEST contribution to total energy expenditure? a. resting metabolic rate b. very low dietary fat intake c. preoccupation with food d. secretive eating

a. resting metabolic rate

Pica

an abnormal craving or appetite for nonfood substances, such as dirt, paint, or clay that lasts for at least 1 month Those with Pica may have -electrolyte and metabolic disorders -intestinal obstruction -wearing away of tooth enamel -gastrointestinal problems Testing for anemia is recommended since pica is associated with iron deficiency.

Feeding and Eating Disorders

anorexia nervosa, bulimia nervosa, binge eating disorder Signs of disordered eating: restrictive eating, fasting, skipping meals, taking diet pills, laxatives, or diuretics.

1. The primary macronutrient that is addressed in the precompetition meal is a. fat b. carbohydrate c. protein d. vitamin

b. carbohydrate

Minimizing gastrointestinal issues

-Try food in practice first. -When the meal is closer in time to the start of the game or event, consume smaller amounts of food and liquids. -Avoid high-fat and high-fiber foods. Both slow down digestion, which may result in stomach cramps. -Avoid sugar alcohols. Consumption can cause gas, bloating, cramping, and a laxative effect.

Postcompetition nutrition (Concurrent training)

- The consumption of carbohydrate after endurance exercise and prelift can help suppress skeletal muscle breakdown. - For optimal muscle remodeling, at least 20 to 30 g of protein should be consumed per meal and meals should be eaten every 3 to 4 hours.

Precompetition nutrition for aerobic endurance recommendations

-Athletes should prehydrate, if necessary, several hours before exercise to allow for fluid absorption and urine output. Their urine specific gravity (USG) reading should be <1.020 -Athletes who tend to get nauseated easily, who get diarrhea during competition, who get anxious or experience precompetition jitters, or who compete in high-intesity sports (jarring movements can increase the likelihood of stomach upset) as well as those who are competing in the heat, may want to consider eating at least 4 hours before competition. Aerobic endurance athletes who eat at least 4 hours before competition should include about 1 - 4 g of carb per kg body wt -If the precompetition meal is consumed 2 hours before exercise, athletes should aim for about 1 g carb per kg body wt. During prolonged activity in hot weather, they should consume a sports drink containing 20 - 30 mEq of sodium (460-690 mg with chloride as the anion) per liter and carb with concentration of 5-10%. -When consumed closer to the start of competition, the preexercise meal should be smaller. In addition, liquid sources of carbohydrate may be preferable when the preexercise meal is 1 hour before the event because they are emptied from the stomach faster than solid food. Gels, gummies and similar sources of carbs are digested very quickly.

Nutrition strategies for altering body composition

-Basal metabolic rate is by far the largest contributor to total energy expenditure accounting for about 65% - 70% of daily energy expenditure. *measure of the calories required for maintaining normal body functions such as respiration, blood circulation and gastrointestinal and renal processing. *basal metabolic rate is measured after an overnight fast with subject resting supine and motionless but awake. *Resting metabolic is often used instead of BMR due to the ease of measurement yet it is 10-20% higher than BMR due to increased energy expenditure resulting from recent food intake or physical activity completed earlier in the day.

symptoms of bulimia nervosa

-Chronically inflamed and sore throat -Swollen salivary glands in the neck and jaw area -Worn tooth enamel, increasingly sensitive and decaying teeth as a result of exposure to stomach acid -Acid reflux disorder and other gastrointestinal problems -Intestinal distress and irritation from laxative abuse -Severe dehydration from purging of fluids -Electrolyte imbalance (too low or too high levels of sodium, calcium, potassium, and other minerals), which can lead to heart attack.

During-event nutrition (aerobic endurance sports)

-Consuming carbohydrates during prolonged aerobic endurance exercise can improve performance while also reducing exercise-induced stress and suppression of immune system functioning. -sports drinks can't keep up with carb utilization during prolonged intense activity (28-144 g/hr of carb can reduce reliance on limited glycogen stores, extend time to exhaustion and improve performance by providing a steady stream of carb that can be used for energy. -carbs consumed don't exceed 1.0-1.1 g/min likely due to rate of glucose absorption. (carbs have a different absorption rate and receptors can become exhausted so best to consume a variety together) [isocaloric - amount of just one type of sugar]

Protein at Mealtime Post Competition

-For optimal muscle remodeling, at least 20-30 g of protein per meal and eating meals every 3-4 hours -In kids, don't have to follow per meal protein rules for adults because drive in kids for protein synthesis is regulated by insulin and calorie intake as opposed to leucine. (kids can eat protein in smaller amounts throughout the day)

Weight (fat) loss

-No difference between the amount of weight loss on a low-carbohydrate as compared to a low-fat diet. -Weight loss during dieting may come from muscle, and caloric restriction may decrease muscle protein synthesis. -Athletes should consume 1.8 to 2.7 g protein/kg body weight per day in addition to maintaining a moderate energy deficit of approximately 500 calories per day. **total calorie intake and the ability to stick with the diet overtime are the most important factors.

Symptoms of Anorexia Nervosa

-Thinning of the bones (osteopenia or osteoporosis) -Brittle hair and nails -Dry and yellowish skin -Growth of fine hair all over the body (lanugo) -Mild anemia and muscle wasting and weakness -Severe constipation -Low blood pressure, slowed breathing and pulse -Damage to the structure and function of the heart -Brain damage -Multiorgan failure -Drop in internal body temperature, causing a person to feel cold all the time -Lethargy, sluggishness, or feeling tired all the time -Infertility

What influences BMR and RMR

-fat-free mass - explains 70-80% of the difference in RMR among people -age -nutrition status -genetics -differences in endocrine functioning (hyper and hypo throidism

Precompetition Nutrition

-helps to provide fluid to maintain adequate hydration and carbohydrate to maximize blood glucose and stored glycogen levels and reducing hunger -glycogen is the main form of energy used during high-intensity exercise - once depleted athlete will have muscular fatigue -food should be familiar to athlete (tried in practice) -low in fat and fiber -have moderate protein -can be either high or low glycemic index before competition

Postcompetition nutrition (High-Intensity Intermittent Sports

-high-intensity intermittent sports can lead to some degree of muscle damage depending on many factors including the time and intensity of play and body size. -consuming protein postexercise helps decrease some markers of muscle damage. The amount is unclear

During-event nutrition

-important factor during aerobic endurance events lasting greater than 45 min, intermittent-activity sports, or when an athlete has multiple events in one day. -proper hydration is essential for performance while also helping to prevent overheating, dehydration and heat illness. -athletes should hydrate themselves several hours before exercise to allow for fluid absorption and urine output before competing. -consume enough fluid during exercise to prevent water weight losses exceeding 2% of body weight. -optimal sports drink contains 20-30 mEq of sodium (460-690 mg with chloride as the anion) per liter and carb concentration of 5-10% but 6-8% may be ideal.

Precompetition nutrition for aerobic endurance

-most important for athletes who compete in long-duration activity (>2 hrs) in the morning after an overnight fast. (blood sugar levels and glycogen levels are depleted during overnight fast) -high carbohydrate preexercise can help improve aerobic endurance running capacity -if early start time for a race, practice eating small amounts of food 1-2 hours before a run to acclimate body. Need to sleep and not practical to wake at 3-4am to eat.

Precompetition carbohydrate loading

-potential benefits for distance runners, road cyclists, cross-country skiers, etc... and may conceivably benefit other athletes as well. -3 days of high carb diet in concert with tapering exercise the week before competition and complete rest the day before the event. -8-10 g of carb per kg body wt per day (maybe 10-12 g for runners 36-48 hours before marathon) -women who habitually consume less than 2400 cal/day have difficulty consuming greater amounts of carbohydrate. Therefore, women may have to increase total energy intake above 2400 calories in addition to consuming higher-carb diet in order to increase glycogen stores. -The degree of benefit derived from carb loading varies among individuals, even among aerobic endurance athletes. Therefore athletes should determine the value of this regimen while weighing any negative side effects, such as temporary weight gain in practice before competition.

Postcompetition nutrition (Aerobic endurance events)

-replenish carb stores before next training or competition and consume enough protein to build and repair muscle. -glycogen synthesis has 2 phases 1. first phase is independent of insulin and lasts 30-60 min and occurs rapidly 2. 2nd phase glycogen synthesis occurs at a much slower rate and lasts several hours. -1.0 - 1.85 g per kg body wt right after exercise and at regular intervals every 15 - 50 min thereafter for up to 5 hours -if you have more than a 24 hour rest period you don't have to eat right after, but need to consume adequate carbs. -protein needs to be included to help muscle building and repair and also increases the rate of glycogen storage if carb intake is adequate (i.e. 1.2 g of carb per kg body wt per hour)

Postcompetition nutrition (Strength and Power sports)

-strength and power sports rely on both blood glucose and glycogen for energy during competition. -focus on higher-glycemic carbs immediately postexercise if they must compete or train again over the course of the 24-hour period after the initial training session or competition. -The amount of carbs needed depends on: *intensity *time spent competing *overall body weight and muscle mass *their preexercise meal and state of glycogen stores before competition *whether or not they consumed carbs during competition -Although carbs have no effect on muscle breakdown, they help attenuate acute protein breakdown resulting from resistance training -Increase in protein breakdown likely depends on the resistance stimulus, the person's overall nutrition intake, and dietary intake before and during training or competition. -Muscle protein breakdown has a role in protein balance, muscle protein synthesis plays a much bigger role in overall protein balance. -Supplementing protein after muscle-damaging bout of resistance training increases acute muscle protein synthesis. -Maximal stimulation of protein synthesis occurs with 20-25 g (providing 8.5 -10 g of essential amino acids) high-quality, high-leucine, fast protein (one that leads to a rapid rise in amino acids in the bloodstream) in younger individuals -older people: 40 g or more may be necessary -larger doses of rice effectively stimulated muscle protein synthesis when matched for leutine content. -Younger adults: protein dose containing 2-3 g of leucine or .06 g of leucine per kg per body wt will maximally stimulate muscle protein synthesis

During-event nutrition (Intermittent high-intensity sports)

-tennis: 200-400 ml (6.8-13.5 oz) per changeover (switching sides)

Bulimia Nervosa (BN)

An eating disorder characterized by -recurrent episodes of uncontrolled binge eating -recurrent inappropriate compensatory behavior such as self-induced vomiting, laxative misuse, diuretics, or enemas (purging type), or fasting and/ or excessive exercise (non-purging type); -episodes of binge eating and compensatory behaviors occur at least twice per week for three months; -self-evaluation is heavily influenced by body shape and weight -episodes do not occur exclusively with episodes of anorexia.

anorexia nervosa

An eating disorder characterized by an obstinate and willful refusal to eat, a distorted body image, and an intense fear of being fat -Restirction type and benge-eating or purging type. -average onset is 19

Rapid weight loss

Athletes may use a variety of techniques to cut weight quickly in order to compete in a desired weight class, meet a weight goal set by their coach, or improve performance. -Athletes who lose weight too fast may lose lean body mass, feel fatigues, experience headaches or mood swings, decrease performance, can have other potential serious side effects like: -dehydration, heat illness, muscle cramping, fatigue, dizziness, suppressed immune system functioning, hormone imbalances, hyperthermia, reduced muscle strength, decreased plasma and blood volume, low BP, electrolyte imbalances, kidney failure (diuretic abuse), fainting, death.

During-event nutrition (strength and power sports)

Carbohydrates are also an essential source of energy used during resistance training and therefore in strength and power sports. Strength and power athletes can maintain their glycogen stores, which may decrease muscular fatigue in slow-twitch fibers and possibly lead to better performance, by supplementing with carbohydrate before and during competition.

Avoidant/Restrictive Food Intake Disorder

Characterized by a failure to eat adequately with one or more: -significant weight loss or failure to achieve expected weight gain -significant nutritional deficiency -dependence on a feeding tube or nutritional supplements -marked interference with psychosocial functioning. Only diagnosed when there is no medical condition that accounts for the symptoms. Is associated with failure to thrive syndrome.

3rd component of individual's energy requirement is

Diet-induced thermogenesis - the increase in energy expenditure above the RMR that can be measured for several hours following a meal. - it includes: energy cost of digestion, absorption, metabolism and storage of food in the body. *thermic effect of food accounts for about 10-15% of total calories burned each day. Cunningham equation is more applicable to athletes RMR = 550 + 22(LBM) LBM is lean body mass Also quick way is table 10.4 pg 217

Food and Fluid intake guidelines

Due to large variations in sweat rates and electrolyte concentrations, athletes should measure weight changes during training and competition in specific weather conditions and develop individualized hydration strategies based on this information. During prolonged activity in hot weather use sports drinks containing 20-30 mEq of sodium (460-690 mg with chloride as the anion) per liter, 2 - 5 mEq of potassium (78-195 mg) per liter, carb concentration of 5% - 10%) -children weighing 48 kg (88 pounds): 5 oz of cold water or salted beverage every 20 min during practice -adolescence weighing 60 kg (132 pounds): 9 oz of every 20 min even if they don't feel thirsty. -sodium chloride concentration of 15-20 mmol/L (1g per 2 pints) -9 oz is a lot of fluid and may need to be adjusted -Aerobic endurance athletes should consume 30-90 g of multiple types of carbs together, such as sucrose, fructose, glucose or maltodextrin, each hour during prolonged aerobic endurance activity. -Tennis players should aim for about 200-400 ml fluid per changeover and have of this fluid from a carb-electrolyte sports drink

Carbohydrate loading is an effective strategy to maximize glycogen storage.

However, athletes must consume 8-10 g of carb per kg body wt per day during the loading period to notice any benefit from carbohydrate loading.

Overweight and Obesity (waist circumference)

Men > 40 inches (102 cm) Women > 35 inches (88 cm) Increased relative risk for disease CSCS professionals should use more accurate measurments like skinfolds or dual-energy X-ray aborptiometry (DEXA) in athletes

Overweight and Obesity

Overweight: BMI > 25 Obesity: BMI > 30 -Increase person's risk of morbidity from: HTN, dislipidemia, coronary heart disease, gallbladder disease, stroke, type 2 DM, sleep apnea, osteoarthritis, respiratory problems, endometrial, breast prostate and colon cancers. -disease that affects 34.9% of adults and 17% of children in US Causes -interaction of genes and environment -social behavioral, cultural, metabolic, physiological and genetic factors **Weight loss goal should be 10% of initial weight within 6 months. **BMI should not be used as a diagnostic tool but as an initial screening tool to identify potential weight issues

2nd largest component of individual's energy requirement is

Physical activity. -typically 20-30% of total daily energy expenditure is from physical activity. (this number may be considerably higher in athletes) -highest energy costs are in aerobic activities performed by large athletes for long time periods. Lowest energy costs are skill and power sports performed by smaller athletes.

binge eating disorder

a disorder characterized by compulsive overeating Binge episodes are associated with 3 or more of the following: -eating much more rapidly than normal -eating until feeling uncomfortably full -eating large amounts of food when not feeling physically hungry -eating alone because of feeling embarrassed by how much one is eating -feeling disgusted with oneself, depressed, or very guilty afterward Binge episodes are not followed by purging.

5. To maintain hydration during competition lasting less than 1 hour, it is recommended that athletes consume 3 to 8 oz of water or a sports drink about every a. 15 minutes b. 30 minutes c. 60 minutes d. 2 hours

a. 15 minutes

4. When an eating disorder is suspected, the strength and conditioning professional should a. monitor the athlete's daily food intake b. require frequent weigh-ins c. encourage further assessment by an eating disorder specialist d. provide nutritional information

c. encourage further assessment by an eating disorder specialist

3. Which of the following is characteristic of anorexia nervosa? a. normal body weight b. very low dietary fat intake c. preoccupation with food d. secretive eating

c. preoccupation with food

Rumination Disorder

the regurgitation of recently eaten food into the mouth followed by either rechewing, reswallowing, or spitting it out. Must display this behavior for at least one month and not related to any other medical condition.

Calculating BMI (Body Mass Index)

weight (kg) / height (meters)squared [weight (pounds) / height (inches)squared] x 703