Chapter 10 Nutrition: Fitness and Sports

These flashcards cover key terms and concepts related to nutrition, physical fitness, and sports from the lecture notes.

Physical Activity

Any movement of skeletal muscles that requires energy.

Types of Activities

Moderate Intensity, vigorous intensity, muscle strengthening

Moderate Intensity Definition

Moderate intensity- aerobic activity that increases heart and breathing (examples: brisk walking dancing swimming bicycling level terrain)

Vigorous Intensity

aerobic activity that greatly increases heart rate and breathing examples: jogging tennis swimming continuous laps, bicycling uphill

Muscle Strengthening.

Activity that increases skeletal muscle strength power endurance and mass. Examples: Strength training resistance training muscle strength and endurance exercises.

Physical Fitness

The ability to perform moderate to vigorous activity without undue fatigue.

Exercise

Physical activities that are planned, repetitive, and intended to improve physical fitness.

Moderate Intensity Activity

Aerobic activity that increases heart rate and breathing, such as brisk walking or dancing.

Vigorous Intensity Activity

Aerobic activity that greatly increases heart rate and breathing, such as jogging or swimming continuous laps.

Muscle Strengthening Activities

Activities that increase skeletal muscle strength, power, endurance, and mass, including strength training.

Physical Activity Guidelines for Americans

Recommendations for weekly physical activity: 150-300 minutes of moderate-intensity aerobic physical activity or 75-150 minutes of vigorous-intensity activity

OR an equivalent combo of mod and vigorous intensity aerobic activities. Muscle strengthening activities that involve all major muscle groups on 2 or more days a week.

Assess Your Level of Physical Activity- Levels of Aerobic Physical Activity

Inactive, insufficiently active, active, highly active

Levels of Aerobic Physical Activity- Inactive Definition

means you are not getting moderate to vigorous intensity activities beyond daily life activities.

Levels of Aerobic Physical Activity- Insufficiently active Definition

engaging in some moderate or vigorous intensity physical activity but less than 150 minutes of moderate intensity physical activity per week or 75 min of vig intensity physical activity (or equal combo). This level is less than the target range for meeting the key physical guidelines for adults

Levels of Aerobic Physical Activity- Active Definition

doing the equivalent of 150-300 min of moderate intensity physical activity per week. This level meets the key guideline target range for adults.

Levels of Aerobic Physical Activity- Highly Active Definition

means you are meeting the equivalent of more than 300 min of moderate intensity physical activity per week. This level exceeds the key guideline target range for adults

Sports dietitians

trained professionals who can help you set reasonable physical activity goals based on your current level of fitness. Board certification as a specialist in sports dietetics (CSSD) credential is the premier professional sports nutrition credential in the US.

Wearable Fitness trackers

pedometers accelerometers gpa smartphone apps. Can provide motivation and reinforce behavior.

Anaerobic Metabolism

A process that supplies energy for short bursts of intense activity when oxygen supply to muscles is limited.

Stored ATP (Adenosine Triphosphate)

Immediate source of energy for body functions that must be constantly reformed. Cells must constantly and repeatedly use and then reform ATP using a variety of energy sources.

Phosphocreatine (PCr)

A high energy compound used to resupply ATP, primarily during bursts of activity.

Enzymes split PCr into phosphate and creatine.

Releases energy to reform ATP.

Used primarily during bursts of activity such as lifting and jumping. Can sustain muscle contraction for about 15 seconds.

Anaerobic Glucose Breakdown

The process of breaking down glucose into pyruvate and then lactate during intense physical activity such as sprinting. When oxygen supply to muscles is limited.

During intense physical activity limited oxygen 30 seconds to 2 minutes of work

Lactate (lactic acid) is a chemical produced when cells break down carbs for energy

Replenished ATP quickly: produced 2 ATP per glucose, approximately 5% of total energy potential, cannot sustain ATP production.

Aerobic: glucose protein fat

Anaerobic; glucose only

Aerobic Metabolism

Fuels prolonged, lower-intensity activity using carbohydrates, fats, and proteins when plenty of oxygen is available.

Aerobic Metabolism Fuels prolonged lower intensity activity: Carbs

During low to moderate intensity physical activity (jogging, distance swimming).

Glucose made from liver glycogen released into bloodstream.

Aerobic glucose breakdown when plenty of oxygen is available. Supplies more ATP than anaerobic processes but releases energy more slowly. Approx 95% of the AP made from complete glucose metabolism to CO2 = H2O. When muscle glycogen is depleted blood glucose declines hitting the wall (or bonking)

Aerobic Metabolism Fuels prolonged lower intensity activity: Fats

is an advantageous fuel for muscles plenty stored and concentrated source of energy (9kcal.g).

During physical activity —> fatty acids are released from adipose tissue -→ bloodstream —> travels to muscles where they are taken into cells and broken down aerobically —> ATP + carbon dioxide and water.

Ability of muscles to use fat or fuel depends on the intensity of exercise prolonged moderate/low intensity > fat.

As intensity increases > carbs

Aerobic Metabolism Fuels prolonged lower intensity activity: Protein

During rest and low moderate intensity exercise- provides approximately 5% of energy needs.

During endurance exercise provides 10-15% of energy needs

Branched chain amino acids (BCAA) provide most energy

Resistance exercises uses less protein.

Average dietary pattern: Provides ample amount of these amino acids. Supplements not needed.

Calories

Individual kcal needs vary greatly. Genetics hormones age sex height weight temperature altitude stress physical health medications body composition and training level.

Body mass index not recommended for athletes

body composition better indicator of needs

estimates of energy required to sustain moderate activity: 3.5 to 7 kcal per minute

Relative Energy Deficiency in Sport (RED-S) Female Athlete traid syndrome

Historically been linked to low energy stability (LEA)

concept has been expanded to include male athletes

extends beyond bone and menstrual health

Highest prevalence of LEA involves weight sensitive endurance sports

Relative Energy Deficiency in Sport (RED-S)

A syndrome impacting athletes' health due to low energy availability, affecting bone health and performance.

Relative energy Deficiency in Sport (RED-S) address full range of concerns including;

amenorrhea (females)

reduced testosterone levels and libido (males)

suboptimal bone health

increased risk of illness and injuries

gastrointestinal disturbances

cardiovascular disease

impaired training capacity

poor performance

Athletes Nutritional Requirements Carbohydrate

low intensity: 3-5g/kg/day 210-350g/day

Moderate: 5-7g/kg/day 350-490g/day

High intensity: 6-10g/kg/day 420-700g/day

Extreme: 8-12g/kg/day 560-840g/day

Athlete’s Nutritional Requirements Protein Fat and Fluids

for muscle building and maintenance 1.2-2.0g/kg of body weight is appropriate for most athletes

Timing: consume 0.3-0.4g/kg of body weight of protein every 3-5 hours to ensure adequate supply

Vitamins and Minerals: Athletes

Needs for micronutrients are same or slightly higher than sedentary individuals. Higher calorie intake increases vitamin and mineral intake.

Vitamins and Minerals Exceptions

events where low body fat is crucial. Vegetarian athletes consuming fortified foods or a balance multivitamin may be beneficial

B Vitamins

Support energy metabolism, function as coenzymes, facilitate chemical reactions generating ATP from carbs proteins and fats. With athlete’s higher volume of energy metabolism increased demand for coenzymes.

Support red blood cell health. Folate and vitamins B6 and B12 involved in the formation of healthy red blood cells which transport oxygen.

Antioxidant Nutrients

Prevent oxidative damage. Vitamins E and C antioxidant properties. athletes slightly higher needs. Eat foods rich in antioxidants fruits veggies whole grain breads and cereals vegetable oils. Large doses of vitamins E and C not recommended for athletes.

Iron

iron deficiency impairs performance. Women at risk because of iron loss with menstruation.

Iron: Sports Anemia

condition where there is an increase in blood plasma volume but not RBC= iron labs may look low.

Iron supplements

may cause toxic effects negative impacts on performance. Focus on consuming iron rich whole foods.

Calcium

Calcium deficiency increases risk of stress fractures.

Female athletes who don’t menstruate regularly have bones far less dense than those of nonathletes and female athletes who menstruate regularly.

Calcium intake is important but doesn’t compensate for effects of menstrual irregularities.

weight restricted athletes should make sure they are consuming enough calcium protein and other essential nutrients.

Vitamin D

Relationship found between vitamin D status and injury prevention, improved neuromuscular function, enhanced muscle size. Decreased inflammations reduced risk of stress fractures

Vitamin D deficiency risk for athletes

athletes who live at latitudes above the 35th parallel. Athletes who predominantly train indoors. Current data doesn’t support vitamin D as an ergogenic acid

Athlete’s Nutritional Requirements Hydration

Before: recommended to drink 5-7ml of fluid per kg of body weight 2-4 hrs. before activity

During: avoid fluid losses of more than 2% of body weight to avoid dehydration.

After: for every pound lost during activity it is recommended to drink 2-3 cups of fluids in the first 4-6 hours after activity.

Fluid

Needs of average adults: 9 to 12 cups for females 13 to 16 cups per day for males. Athletes need more

Maintenance of body’s cooling system: Water helps dissipate heat from working muscles. Avoid losing more than 2% of body weight during exercise.

Thirst not reliable indicator of fluid needs

Urine color no darker than lemonade.

Sports Drinks

for activities greater than 60 min

help maintain blood glucose level and blood volume

delays hitting the wall

typically contain added sugars (6-8%) sodium and potassium

for activities less than 60 min water lost through sweat is main concern nutrients easily replaced by diet

Sugars total 14g per cup 240mL serving

Recovery Beverage

A drink, such as low-fat chocolate milk, that aids in recovery by providing carbohydrates and protein.

Carbohydrate Loading

A strategy to maximize glycogen storage before endurance events.

Fat Adaptation

Training strategy where the body is conditioned to use fat as a primary fuel source.

Ergogenic Aid

A substance or treatment intended to directly improve exercise performance.

Endurance Athletes: Strategies to delay or Prevent Fatigue

Carb loading: goal to maximize glycogen storage before event. For events lasting longer than 60 to 90 minutes. Increases muscle glycogen stores 50-90% additional water weight possible disavantage.

Carbohydrate Loading May Be Beneficial for These Activities

marathons, long distance swimming, cross country skiing, 30 km runs, triathlons

Maximize Glycogen Stores Before the Event

Light Meal 1 to 4 hours prior to event

primarily of carbs(top off glycogen stores)

moderate fat and fiber avoid fatty fried foods

High quality protein

blended or liquid meal recommended for meals eaten within 1 hour prior

Pre event meals may require a higher proportion of grains than suggested by MyPlate to boost carbs content. Choose starchy veggies and grain based snacks to help top off glycogen stores.

Fat adaptation High fat training eating plan

25% of calories from carbs. 60-70% of calories from fat.

Cells may adapt to use fat for fuel

Research mixed on the approach and results

Fat Adaptation

popular among endurance athletes

Only 2000 to 3000 kcal available from muscle glycogen.

Limitless supply of energy from triglycerides stored in muscle and adipose tissue

Can supply about half the energy during endurance events

Replenish Fuel During the Event

For events longer than 60 minutes.

Carbohydrate consumption improves performance. Consumer 30 to 60 grams of carbs per hour. Carbs gels or chews are formulated to rapidly supply abt 25g of carbs per serving.

Protein products containing amino acids may provide benefit. Protein bars for endurance should contain approximately 40 g of carbs and no more than 10 g of protein 4 g of fat and 5g of fiber.

Replenish Glycogen and Fluid after physical activity: To rapidly restore glycogen stores-

Consume 1.0-1.2 grams of carbs per kg of body weight within 30 min after endurance physical activity.

Repeat process every 2 hours for the next 4-6 hours.

Fruit Fruit juice bread or a sports drink contribute to rapid restoration of glycogen stores.

Add 0.25 to 0.3 grams of high quality protein per kg fd body weight to stimulate glucose uptake and repairing damaged muscle tissue.

Replenish Glycogen and Fluid after physical activity- glycogen synthesis greatest immediately when:

Glycogen synthesis greatest immediately after exercise. Muscles are insulin insensitive at this point

Recovery Beverage

Low-fat chocolate milk go to recovery drink for many athletes. 1 cup serving is a tasty vehicle for 25g of carbs and 9g of protein.

Sports Anemia

A condition characterized by increased blood plasma volume but a low red blood cell count, often found in athletes.

Body Dysmorphic Disorder

Individuals see themselves as being too thin even though they are more muscular than average. People with BDD practice disordered eating behaviors or use steroids to achieve high levles of muscularity

Nutrition Challenges for Athletes

Overreliance on convenience foods, abundance of nutrition, temptations to eat out of boredom or for emotional comfort, additionally they must adapt to seasonal demands of their sport and maintain exhausting training and travel schedules.

Ergogenic aids include:

sufficient water, electrolytes, adequate carbs, balanced and varied dietary pattern.

Sports Nutrition Supplements Ergogenic aid

A mechanical nutritional psychological pharmacological or physiological substance or treatment intended to directly improve exercise performance.

Sports Nutrition Supplements- US Sports nutrition supplement market is greater than:

$11 billion

Sports Food

Electrolyte supplements may be used for rehydration or hydration by replacing electrolytes lost in sweats. Liquid meals may provide a quick and convenient source of carbs protein and nutrients when eating whole food is not practical. Protein supplements may provide a quick and convenient source of easily digested high quality protein. Sports drinks may be used for hydration and fueling strategies for longer or high quality training sessions or longer races. Sports gels/confectionary may be used for fueling strategies during longer training sessions and races.

Select Dangerous Banned or Illegal Substances and Practices

Alcohol and beta blockers, anabolic steroids (such as testosterone), blood doping, peptide hormones and analogues (such as growth hormone), stimulants (such as caffeine, ephedrine)

Alcohol and beta blockers purported use

decrease anxiety and allow for muscle relaxation

Alcohol and beta blockers risks

changes in blood sugar symptoms of heart failure

anabolic steroids (such as testosterone) purported use

Increase muscle mass and strength

anabolic steroids (such as testosterone) risks

liver cysts increased risk of cardiovascular disease hypertension reproductive dysfunction depression sleep disturbances mood swings

blood doping purported use

enhanced aerobic capacity by increasing cells

Blood doping risks

blood thickening that strains the heart

Peptide hormones and analogues (Such as growth hormone) purported use

increases muscle mass and fat metabolism

Peptide hormones such as analogues (such as growth hormone) risks

uncontrolled growth of the heart and other internal organs death

stimulants (such as caffeine ephedrine) purported use

increases muscle strength and power promotes mental alertness weight loss

stimulants (such as caffeine ephedrine) risks

heart palpitations anxiety and death

Select commonly used supplements for athletes

probiotics, protein powder, ketones, vitamin D, beta hydroxy beta methyl butyric acid (HMB), branched chain amino acids (BCAA), creatine, nitric oxide boosters (arginine, beetroot juice, citrulline)

HMB Beta hydroxy beta methylbutyric acid Purported benefits

Decreased muscle damage speeds up recovery from intense physical activity.

HMB Beta hydroxy beta methylbutyric acid Risks

itching abdominal pain and constipation

Branched chain amino acids (BCAA) Purported benefits

increased energy delivered to muscles during activity to increase muscle size and strength

Branched chain amino acids (BCAA) Risks

increased levels of ammonia in the blood, fatigue, loss of motor coordination, digestive discomfort, nausea, vomiting and diarrhea

Nitric oxide boosters (arginine beetroot juice citrulline) Purported benefits

improved blood flow to muscles and enhanced performance by improving oxygen consumption to deliver nutrients to muscles

Nitric oxide boosters (arginine beetroot juice citrulline) Risks

drop in blood pressure dizziness lightheadedness and loss of balance

Probiotics Purported benefits

improved gut health with mental and physical benefits

Probiotics Potential Risks

Digestive discomfort rash itching infections in certain high risk individuals

Protein Powder purported benefits

provide necessary protein in absence of whole foods increased lean mass production

Protein Powder Potential Risks

high doses can cause nausea thirst bloating cramps diarrhea reduced appetite and fatigue; overreliance on supplements over food can increase potential for poor intakes of other key nutrients.

Ketones purported benefits

support fat burning

Ketones potential risks

shakiness and abnormal heartbeat

Vitamin D purported benefits

increased skeletal muscle function decreased recovery time improved power and support of testosterone production

Vitamin D risks

high doses can cause toxicities, leading to weakness, fatigue, sleepiness, headaches, loss of appetite, dry mouth, metallic taste, digestive discomfort, weight loss, and seizures.