Kin 110 Lecture 10 Ch 11 Fitness and

Kin 110 Lecture 10 Ch. 11 Fitness and Sport 1

Fitness and Sport • Activity and Nutrition are necessary together – good nutrition is essential for performance and – activity is essential for weight control and a healthy body composition • adequate fluid and carbohydrate intake are needed to perform • Physical Fitness - ability to do moderate to vigorous activity without undue fatigue • The type of Fuel used to sustain physical activity is affected by – Fitness level – intensity of activity – diet 2

Benefits of Exercise • Only about 15% of adults practice moderate to vigorous physical activity on a regular basis • Fig 11 -1 - Benefits • Improve overall Fitness • Skill - agility, balance, coordination, reaction time • Health - endurance, body composition, muscular and skeletal fitness • Reduced risk for heart disease – heart muscle and circulation – reduce other risk factors – BP, TG, lipoproteins 3

Benefits of Exercise • Prevents and treats obesity – caloric use – stimulates fat burning and mobilization – Maintain lean body mass • Prevents and controls diabetes – Increases glucose uptake in absence of insulin – Contributes to weight balance • Osteoporosis • Reduce infections • Enhances psychological health 4

Designing a Program • Kinesiology 143 • (PAR-Q) – over 35 speak with a physician before drastically increasing activity • Phase 1 • incorporate 30 minutes of moderate activity into your daily routine – Walk, take stairs, house cleaning, gardening – Effects are cumulative - so they can be broken up into 10 min sections • develop habits and use of body 5

Basic Fitness Program • Phase Two • increase goal to 30 min of more vigorous activity 3 -5 days per week – Fig 11 -2 • include resistance exercise – 2 -3 times per week • Warm-up – slow jog, flexibility (2 -3 per week) • workout – 65 -85 % of Heart Rate Max • heart rate max = 220 - age • cool down – slow jog, flexibility 6

FITTE Formula • Frequency, Intensity, Time, Type and Enjoyment • F - 3 -5 times per week • I - 65 -85% max HR – 4 -6 range on RPE scale p 380 • T - 20 -40 minutes • T - any aerobic activity, repetitive use of large muscle groups – Running, swimming, cycling, circuit training • E - make sure you pick activities that you enjoy • Progression - important to start slowly but also challenge your body to continue to adapt by increasing one component (FIT) at a time 7

Metabolism • All chemical reactions that occur in the body – release of energy from foods – conversion of substances – preparation of excretions • Metabolic pathway – sequence of chemical reactions • Anabolic - building • Catabolic - breakdown – digestion – energy release from carbohydrates and lipids forming CO 2 + H 2 O 8

Energy Sources for Muscle • Table 11. 1 - energy sources • Adenosine Tri-phosphate (ATP) – energy currency for cells – Fig p 381 • ion pumping, enzyme activity, muscle contraction • Solar energy from Sun trapped by plants and stored as chemical energy • ADP + Pi + energy => ATP – ATP stores can sustain muscle for 2 -4 seconds 9

Maintaining ATP • Breakdown of Phospho. Creatine, Carbohydrates, Fats, and Protein maintain ATP • ATP breakdown products activate the splitting of PCr – Phosphocreatine • sustains ATP for about 10 seconds of maximal activity • fastest most powerful activities use this system to replace a majority of ATP 10

Carbohydrates • Blood glucose and Muscle Glycogen • Glycolysis – catabolism of glucose for ATP • First Phase - very rapid – low yield ( 2 ATP / glucose) – Supports activities lasting that can be maximal for 30 sec. to 2 min. • Low O 2 - Anaerobic Glycolysis – intense exercise - Lactic Acid – Acid buildup can inhibit activity 11

Carbohydrate • High O 2 - Aerobic Glycolysis – moderate to low intensity exercise – Oxygen demand can be maintained and can support ATP requirements • breakdown products move to mitochondria – completely broken down into CO 2 and H 2 O • requires O 2 – yields 36 ATP/glucose – more efficient but slower than anaerobic – Predominates for sustained activity lasting 2 min to 4 or 5 hours 12

Carbohydrate Sources • Blood Glucose and Glycogen – Main source is muscle glycogen • Glycogen depletion – exercise capacity is cut in half • Carbohydrate loading – Prevents severe depletion and “hitting the wall” • contribution of blood glucose is very important after 20 -30 min – – carbohydrate intake during exercise 30 -60 g per hour maintain blood glucose delay fatigue 30 - 60 minutes 13

Fats : low intensity fuel • Slow metabolism, important for bouts longer than 20 minutes • massive storage – Adipose – Muscle • caffeine increases availability and utilization • “hitting the wall” - can only sustain a fast walk or slow jog – * because only fuel source is fats* – Carbohydrates have run out • Fig 11 -3 - ATP formation • Fig 11 -4 - fuel use • “ Fat burning Zone? ? ” 14

VO 2 max. = 2. 0 liters/min Conclusion: more fat (and total calories) is/are burned at a higher intensity for exercise over the same duration(time).

Power Foods Dietary Guidelines • Proper diet will maximize an athletes potential • Athletes need to add the energy required for training to the basal requirements – Estimate 5 -8 kcal/min (for moderate activity) • Assessment of body composition is important – body fat %, weight change – Fluid and electrolyte replacement 16

High Carbohydrates • Higher intake for athletes • To replenish glycogen stores • increase carb intake from 5 g/day/Kg to 7 g/day/Kg • focus on carbohydrate rich sources, to supplement needs • 60 - 70 % of kcal from carbohydrates • Fig. 11 -4 – potatoes, brown rice, whole grain pasta 17

Carbohydrate loading • Appropriate for continuous events lasting over 90 min – Marathon, triathlon, basketball tournament, X-country skiing • shorter events repeated within 24 hours - time trials, heats/finals • Table 11. 2 - daily menu • couple with tapering of training (reduction) before competition • caution, can increase water retention with glycogen storage • *Eat Carbo rich foods after exercise Juice, yogurt…* • Recommendations for carbohydrate loading prior to competion - p 389 18

Protein • Small contribution to energy • endurance 10 -15 %, especially with inadequate Carbohydrates • ? Anabolic effect of carbohydrate rich diet? – Insulin, growth hormone • protein generally met by balanced diet • may need increase for high level endurance and weight training athletes – increase to 1. 0 -1. 6 g/Kg body weight • From. 8 g/kg for general population – AA or protein supplements are not necessary 19

Vitamins and Minerals • Same or slightly higher requirements than sedentary • May be some antioxidant protection with higher vitamin C and E • balanced diet should be fine • Iron - deficiency anemia impairs performance • Calcium – osteoporosis, stress fracture risk due to decreased bone density in female athletes no longer menstrating regularly 20

Body Fluids • 6 -8 cups per day • Sweat losses, 3 -8 cups per hour • body temperature increases with loss of 3% body weight in H 2 O – reduced endurance, strength and performance • Heat Illness – profuse sweating, headache, dizziness, nausea, vomiting – maintain fluid intake, avoid intense exercise in extremely hot and humid environments 21

Fluid intake • Drink regularly up to 2 hours before activity ( water, diluted fruit juice, sports drink) • 20 - 30 min before 1 -1. 5 cups • during. 5 to 1 cup every 20 min • 6 -8 % glucose (sports drinks) – otherwise impairs absorption • After, 2 cups per pound lost – One Litre per Kg • Sports drinks? – Carbohydrate and electrolyte replacement in addition to water may be important for events lasting longer than 60 minutes in hot weather 22

Pre Game Meal • Light - 300 -100 kcal – 2 -4 hours before event • primarily carbohydrates (70%) – milk, grapefruit, baked beans, apples – sustained release of glucose • low insoluble fiber • blend food for easy digestion if only 1 -2 hours before event – cliff bar, power bar • ? avoid carbohydrates one hour before event - athlete specific • Table 11. 5 pre event meals 23

After Exercise • Table 11. 7 post event meals • Carbohydrate rich foods within 2 hours - 50 -200 g – fruit juice, candy, sports drinks • electrolyte replacement – Na+, K+ - (salt, banana) • sports drinks most important for 60 - 90 minute events – large loss of sweat (and electolytes) • glucose polymer (linked glucose) - OK – fructose absorbed slowly 24

Learning Objectives • Design a basic fitness program • Describe when and how glycogen, blood glucose, fat and protein are used to meet energy needs during different types of activity • Differentiate between anaerobic and aerobic use of glucose - including advantages and disadvantages • Show muscles adapt to an increase in physical activity • Outline how to estimate an athletes energy needs and the nutrient requirements of a training diet (carbs) • Examine problems with rapid weight loss and dehydration • Describe effects of various ergogenic aids on an athletes performance 25