Sports Nutrition: Eating for Peak Performance BIOL 103, Chapter 11

Nutrition and Physical Performance “Exercise is medicine” Physical fitness is made up for 5 components: Cardiorespiratory fitness: ability of body’s circulatory and respiratory systems to fuel during sustained physical activity. Muscular strength: ability of muscle to exert force during an activity Muscular endurance: ability of muscle to continue to perform without fatigue Body composition: relative amount of fat to lean body mass. Flexibility: the range of motion around a joint

Figure 11.1 Develop an Active Lifestyle To promote health, exercise 30 min/day To achieve and maintain fitness, 29-60 min of continuous activity or intermittent aerobic activity, 3-5 days/week

Energy Systems, Muscles, and Physical Performance ATP-CP energy system: Anaerobic: _____________________________ Quick source of ATP Cellular ATP and _____________________________ Fuel for ___________________ of maximal effort

Energy Systems, Muscles, and Physical Performance Lactic acid energy system “Acceleration stage” Anaerobic Breakdown of _________  _____ and _________________________ Rise in __________ triggers muscle fatigue How? A rise in acidity  impair breakdown of glucose and inhibits _______ binding  _______________ ______________________________ “Acceleration stage”

Energy Systems, Muscles, and Physical Performance Oxygen energy system “Endurance stage” Breakdown of ____________ and _______ for energy in the cell’s mitochondria Requires oxygen (Aerobic) Produces ATP more ____________ because the required oxygen has to travel from lungs all the way to the cell’s mitochondria.

Problem Set 11, Q1 Name the three types of energy system mentioned in class. Classify them into aerobic and anaerobic. How does each of the system acquire energy?

Energy Systems, Muscles, and Physical Performance Teamwork in energy production Anaerobic systems Aerobic systems Glycogen depletion Steady drop of glycogen for first _____________ Entirely depleted at around _____________

Energy Systems, Muscles, Physical Performance Endurance training Training increases number of _____________  improves _____________ enhances aerobic capacity Decreases reliance on anaerobic systems Extends availability of ____________________

Muscles and Muscle Fibers (Problem Set 11, Q2) We have two types of skeletal muscles: Slow-twitch fibers – muscles that develop tension more slowly; have high oxidative capacities __________________________ (aerobic endurance) Ex: __________________________ Fast-twitch fibers – muscles that can develop high tension rapidly. ___________________________________ Ex: ________________________________ Relative proportion determined by ____________

Figure 11.10 Mix of your Muscle Fibers If you are best at events requiring explosive movements, you may have greater percentage of fast-twitch muscle fibers. If endurance events are your specialty, you may have more slow-twitch fibers.

Optimal Nutrition for Athletic Performance Consume _________________________ (first priority for athletes) 6-10g/kg per day of carbs 1.2-1.7g/kg per day of protein 20-35% of total calories from fat Maintain appropriate body weight and body composition Promote ___________________ from training Maintain hydration status

Carbohydrate and Exercise High-carbohydrate diets: Increase ______________ Extend _______________ Carbohydrate loading __________ of calories as carbohydrate __________ exercise intensity prior to competition Not very beneficial if the aerobic activity lasts less than _______ minutes.

Problem Set 11, Q3a Explain what is carbohydrate loading and why it is beneficial to your running.

Carbohydrate intake and Exercise Before exercise Eating carbs 2-4 hours _________ morning exercise helps replenish glycogen stores and improve endurance Recommend ________ portions and ___________ foods/beverages During exercise ___________ (______% carbohydrate + ___________) for events that last at least 1 hour. After exercise Replenish glycogen stores: 1-1.5 grams carbohydrate per body kg both 30 minutes and 2 hours after exercise

Dietary Fat and Exercise Major fuel source for ________________ activities Key point: Endurance training increases the capacity of your oxygen energy system, enhancing your body’s ability to use fat as fuel. High-fat diet __________ needed Recommendations: Moderate fat intake: 20-35% of calories Limits saturated fat to less than 10% of energy Avoid trans fat as much as possible

Protein and Exercise Muscles and strength are built with exercise (not extra protein) and carbohydrates provide the fuel needed for muscle-building exercise. Protein recommendations Adults: 0.8 grams per kg body weight Endurance athletes: 1.2-1.7 g/kg Resistance-trained athletes: 1.6-1.7 g/kg Protein sources Foods: lean meats, fish, low-fat dairy, and egg whites

Proteins and Exercise Protein intake after exercise: Protein combined with carbohydrate consumption after exercising helps replenish _________ more efficiently. Dangers of high-protein intake Diuresis (loss of body water): high protein  high urine production  dehydration + mineral losses High protein diets are neither recommended nor necessary.

Problem Set 11, Q3b Should you still consume dietary fat and protein for your activity? Why or why not?

Vitamins, Minerals, and Athletic Performance B vitamins Needed for ____________ metabolism Calcium Needed for normal _________ function and bones Iron Needed for ___________ delivery and ______________ production Athletes have _________ losses from trauma to the capillaries in the feet.

Fluid Needs During Exercise Exercise and fluid loss increase risk for dehydration Increased losses from _____________ (0.5-2.0 L/hour) Increased with heat, humidity Hydration Adequate fluids ________________________exercise Should drink fluid at rates that match sweat rates Should you drink water vs. sports drinks? Depends on duration and intensity of activities Depends on environmental factors If >60 min, high humidity, or very intense events, recommend ______________________________________

Characteristics of Nutrition Supplements and Ergogenic Aids Ergogenic aids: substances that can ________ athletic performance Provide calories Provide vitamins and minerals Contribute to performance and enhance recovery Are believed to simulate and maintain muscle growth

Nutrition Supplements and Ergogenic Aids Table 11.10 Types of Ergogenic Aids Nutritional, Physiological, Psychological, Biomechanical, Pharmacological Regulation and concerns about dietary and herbal supplements __________ FDA safety and effectiveness regulations Possibility of product contamination

Nutrition Supplements and Ergogenic Aids Weight-gain powders Add an extra 500-1000 calories/day ________% weight gain by high calorie diet is muscle, rest is fat No proof that increasing protein intake above recommended levels improves _______________ Too much protein  ___________________ fat

Nutrition Supplements and Ergogenic Aids and popular theories Creatine – _______________________________ Antioxidants – protect muscles/cells from exercise damage Caffeine – nerve/muscle signal facilitator, might increase ability to break down fat for energy Sodium bicarbonate (baking soda) – to neutralize _______________ Chromium – ________________________ Iron – for anemia Green tea extract – weight loss?