246
Chapter 14 – Fitness: Physical Activity, Nutrients, and Body Adaptations
Learning Objectives
After completing Chapter 14, the student will be able to:
14.2 Identify the factors that influence fuel use during physical activity and the types of activities that depend
more on glucose or fat, respectively.
14.3 List which vitamin and mineral supplements, if any, athletes may need and why.
14.4 Identify the factors that influence an athlete’s fluid needs and describe the differences between water and
sports drinks.
14.5 Discuss an appropriate daily eating pattern for athletes and list one example of a recommended pre- or post-
game meal.
14.6 Present arguments for and against the use of ergogenic aids.
a. Define ergogenic and identify products classified as ergogenic aids.
b. Identify supplements commonly used by the athlete and discuss their safety and efficacy.
c. Identify the hormonal supplements that are promoted to athletes and are illegal or dangerous.
Assignments and Other Instructional Materials
The following ready-to-use assignments are available in this chapter of the instructor’s manual:
• Case Study 14-1: Physical Activity for Fitness and Weight Loss
• New! Case Study 14–2: “Energy Gel” Evaluation
• Worksheet 14-1: Fitness Review (Internet Exercise)
1
• Worksheet 14-2: Physical Activity Self-Evaluation
2
• Worksheet 14-3: Cardiorespiratory Endurance Calculation
• New! Worksheet 14-4: Chapter 14 Crossword Puzzle
3
247
Lecture Presentation Outline
4
Key to instructor resource annotations (shown to the right of or below outline topics):
TRA = Transparency acetates: 13e = 13th edition, 12e = 12th edition, 11e = 11th edition, 10e = 10th edition
I. Fitness IM WS 14-1
A. Benefits of Fitness
1. There are many benefits:
a. Restful sleep
b. Nutritional health
c. Improved body composition
2. Aerobic physical activity
3. Moderate-intensity activity or vigorous-intensity activity
B. Developing Fitness 11e TRA 26; 12e TRA 20; IM WS 14-2, CA 14-1
1. Guidelines for conditioning that is achieved through training (Table 14-2)
2. The Overload Principle
3. The Body’s Response to Physical Activity
1. Be active all week
2. Use proper equipment and attire
3. Use proper form when exercising
7. Build intensity slowly
4. Cautions on Starting a Fitness Program
C. Cardiorespiratory Endurance 10e TRA 149; IM WS 14–3, HN 14-1
1. Cardiorespiratory Conditioning
a. Increases cardiac output and oxygen delivery
248
d. Increases breathing efficiency
e. Improves circulation
f. Reduces blood pressure
2. Muscle Conditioning
endurance
D. Resistance Training
1. Increases muscle strength, power, and endurance
2. Prevents and manages cardiovascular disease
3. Enhances psychological well-being
4. Maximizes and maintains bone mass
5. Improves posture and decreases the risk for back injury
5. Enhances performance in other sports
II. Energy Systems and Fuels to Support Activity
A. The Energy Systems of Physical Activity—ATP and CP
1. ATP is adenosine triphosphate
2. CP is creatine phosphate
3. The Energy-Yielding Nutrients
B. Glucose Use during Physical Activity IM CS 14-2
1. Diet Affects Glycogen Storage and Use (Figure 14-1) 10e TRA 150; IM HN 14–2
a. High-carbohydrate diets increase glycogen stores
4. Duration of Activity Affects Glycogen Use
a. First 20 minutes – primarily use glycogen
b. After 20 minutes – use glycogen and fat
5. Glucose Depletion
a. “Hitting the wall”
b. Maximizing glucose supply
1. High-carbohydrate diet
2. Glucose during activities lasting longer than 1 hour
3. Eat foods providing approximately 60 g of carbohydrate after activity
4. Carbohydrate loading
8. Training Affects Glycogen Use
a. Muscles that repeatedly deplete their glycogen adapt to store more
b. Conditioned muscles rely less on glycogen and more on fat
c. Trained muscle cells have more mitochondria
d. Untrained muscle cells depend more heavily on anaerobic pathways
D. Protein Use during Physical Activity—and between Times
1. Protein Used in Muscle Building
a. Synthesis of protein is suppressed during activity
b. After activity protein synthesis accelerates
c. Remodeling
2. Protein Used as Fuel
3. Diet Affects Protein Use during Activity
4. Intensity and Duration of Activity Affect Protein Use during Activity
a. If glycogen stores get depleted, then more reliance on protein for energy
b. Anaerobic strength training uses more to build muscle
III. Vitamins and Minerals to Support Activity
A. Dietary Supplements
1. Do not enhance performance
2. Deficiencies may impede performance
3. Timing makes a difference
4. Nutrient-dense foods provide nutrients needed
B. Nutrients of Concern
IV. Fluids and Electrolytes to Support Activity IM CA 14-2
A. Temperature Regulation
1. Muscle heat is 15-20 times greater when active than at rest.
250
2. Hyperthermia
a. Body heat builds up
3. Hypothermia
a. Loss of body heat
b. Symptoms of hypothermia
4. Fluid Replacement via Hydration
1. Two to three hours before activity – 2-3 cups
2. 15 minutes before activity – 1-2 cups
3. Every 15 minutes during activity – ½-1 cup
4. After activity – 2 cups for every pound of body weight lost
a. Decreased concentration of sodium in the blood
b. Causes
c. Symptoms
d. Prevention
B. Sports Drinks IM HN 14-3
1. Fluid
V. Diets for Physically Active People
A. Choosing a Diet to Support Fitness 10e TRA 151
1. Water
2. Nutrient Density
3. Carbohydrate
4. Protein – Emphasize healthy sources of protein
B. Meals before and after Competition IM CA 14-3
1. Pregame Meals (Figure 14-2)
a. Fluids
2. Postgame Meals
a. High-carbohydrate meals
251
b. Liquids often preferred
VI. Highlight: Supplements as Ergogenic Aids IM CA 14-5, HN 14–4, 14-5
A. Dietary Supplements that Perform as Claimed
1. Convenient Dietary Supplements
2. Caffeine
Case Studies
5
Case Study 14-1: Physical Activity for Fitness and Weight Loss
Theresa is a 17-year-old high school student who gained 20 pounds her junior year of high school when she quit the
girls’ soccer team and joined the debate team. She is 5 feet 2 inches tall and weighs 154 pounds. She has been
monitoring her food intake for 2 weeks and reports eating about 1600 kcalories a day. Although her weight is stable
at this calorie level, she would like to lose weight. She notes that she does not get regular exercise and wants to
become more physically fit. She comes to you for a diet and exercise program that will help her achieve her goals.
1. What information about the benefits of muscle conditioning might encourage Theresa in her weight–loss
efforts?
2. Briefly explain to Theresa the three basic components of a balanced fitness program and the necessity for each
component.
3. Using the guidelines presented in Table 14-2, set up a weekly schedule of fitness activities for Theresa. Include
specific exercises and the frequency and duration of each exercise.
4. Considering Theresa’s goal to lose weight, what type of exercise would be most conducive to fat loss? Give
examples.
5. Calculate how many kcalories from carbohydrates, fat, and protein are provided in a 1600-kcalorie diet that
derives 60 percent of calories from carbohydrate, 25 percent from fat, and 15 percent from protein. Calculate
the amount of each of these nutrients (in grams) for Theresa to consume each day. (Remember that 1 gram of
carbohydrate or protein yields 4 kcalories and 1 gram of fat yields 9 kcalories.)
6. Assuming Theresa will begin her exercise program this week, what advice for fluid intake would you
recommend (including type and amount)?
Answer Key
1. Fit muscles use oxygen efficiently and also burn fat longer, which can improve Theresa’s body composition and
help her lose weight. Physical activity expends energy, which may allow her to lose weight without severely
restricting calories. Muscle conditioning can also increase the body’s ability to burn calories (expend energy).
252
Case Study 14–2: “Energy Gel” Evaluation
Kaitlyn F. is a 21-year-old woman who has taken up running in an effort to lose weight and improve her endurance.
She runs 3 to 4 days a week for approximately 45 minutes to an hour. At the store, she finds a sports “energy gel”
labeled as a “natural performance enhancer.” Each 1.1-ounce package provides 100 kcalories, 40 milligrams
sodium, 30 milligrams potassium, and 25 grams total carbohydrates. The directions read: “For best results, consume
one package 15 minutes before activity, one to two packages per hour during activity and one package immediately
after activity to aid in recovery. Always follow consumption with water.”
Kaitlyn is trying to determine whether she needs this product for her training regimen.
1. Based on information in this chapter, what main ingredient in this product would Kaitlyn expect to be a “natural
performance enhancer”? Explain.
2. Considering her current level of activity, what is the most important nutrient that Kaitlyn needs to consume
before her workout?
3. How might Kaitlyn decide whether she needs this type of product during her workouts?
4. What ingredient in this product might “aid in recovery” after physical activity?
5. What effect might this product have on Kaitlyn’s weight–loss efforts if she uses it as directed?
6. Given the length of her workouts, explain how Kaitlyn can easily replenish glucose and electrolytes after
exercising without using a special product.
Answer Key
1. Glucose can enhance endurance and performance in strenuous competitive events.
Suggested Classroom Activities
Fitness and athletics are receiving much attention these days and as a result students are often interested in how
nutrition can support physical activity. This chapter will assist students by providing information about the benefits
of exercise and how to nourish themselves for optimal performance.
253
Classroom Activity 14-1: Physical Activity Diary
Key concept: Evaluation of physical activity Class size: Any
Instructions: Instruct students to keep an activity log or diary in which they can record physical activities they
participate in daily. Have them keep the record for seven days, and ask them to bring the record to class. Divide
students into groups and have them evaluate their activity patterns. (You could use Worksheet 14–3 in conjunction
with this activity.)
Classroom Activity 14-2: Sports Drinks Evaluation
Key concepts: Maintaining hydration, sports drinks composition Class size: Any
Instructions: Have students research 4 to 6 different sports drinks. Have them list the amount of glucose, sodium and
other electrolytes present in each product. Instruct students to list the advantages and disadvantages of these
products in addition to water and provide their recommendations about the best choice. Discussion can progress
regarding cost of the sports drinks as well as taste.
Classroom Activity 14-3: Pre- and Post-Game Food Choices (Meal Comparison)
6
Key concept: Diet planning for athletic performance Class size: Any
Instructions: Present the pre-game and post-game meal plans for an athlete below to students and use the discussion
questions to prompt them to evaluate the plans.
Post-game meal
Yogurt, low-fat, 1 cup
Raisin Bran cereal, 1 cup
Pear, fresh, 1 medium
1% milk, 1 cup
Discussion questions:
1. What are the general recommendations for a pre-game meal?
2. How can the pre-game meal plan be modified to fit the recommendations?
3. What are the general recommendations for a post-game meal?
4. How can the post-game meal plan be modified to fit the recommendations?
Answer key:
1. High in fluids, high in carbohydrates (that are easily digested and familiar to the athlete), low in fiber, low in
Spaghetti, 2 cups
5
Yogurt, low-fat, 1
cup
8
0
6
Marinara sauce, 1 cup
5
4
Raisin Bran cereal, 1
cup
8
5
Papaya, raw, 1 cup
1.7
0.5
Pear, fresh, 1
medium
6
5
Broccoli, raw, 1 cup
7
3
3
1% milk, 1 cup
0
8
14.7
23.5
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Classroom Activity 14-4: Fitness Facility Evaluation
Key concept: Evaluation of fitness facilities Class size: Any
Instructions: Instruct students to visit a local fitness facility and investigate the dietary advice they offer as part of
the service. Do they sell nutrient supplements? What qualifications or training in nutrition do the fitness instructors
have?
Classroom Activity 14-5: Fitness Quackery Evaluation
Key concept: Evaluation of fitness information from the media Class size: Medium to small
Instructions: For a fitness quackery activity, ask students to bring in newspaper and magazine advertisements and
brochures for food supplements and products they believe represent exercise and fitness quackery. Ask what
characteristics of the advertisement led them to this conclusion, and whether the use of this food product might pose
a danger to one’s health. The importance of this activity is that this is an area of quackery that has become a
booming business in America. As consumers, students not only should be aware that these problems exist but should
know how to distinguish between health-promoting products and those that are fraudulent.
How To “Try It” Activities Answer Key
How to Calculate the Carbohydrate Concentration of Sports Drinks
14 g 240 mL = 0.0583 100% = 5.8% carbohydrate
Study Card 14 Answer Key
1. The progressive overload principle is the training principle that a body system, in order to improve, must be
worked at frequencies, durations, or intensities that gradually increase physical demands. That is, an individual
2. Cardiorespiratory conditioning refers to improvements in heart and lung function and increased blood volume
10. Physically active young women, especially those who engage in endurance activities such as distance running,
are prone to iron deficiency. Habitually low intakes of iron-rich foods (especially among vegetarians), high iron
losses through menstruation, and the high demands of muscles for the iron-containing electron carriers of the
255
13. The body relies on watery fluids as the medium for all of its life-supporting activities, and if it loses too much
water, its well-being will be compromised. Mild dehydration hinders performance by causing fatigue, and as it
worsens it can cause more serious symptoms such as nausea, collapse, or even death if the body’s core
14. a 15. d
Critical Thinking Questions
7
1. Describe ways to improve one’s level of physical activity.
2. How should the heart respond to physical activity in order for an individual to gain maximum cardio
conditioning benefits?
3. How does the type of physical activity affect fuel utilization in the body?
4. Explain why vitamin E and iron supplements may be needed for health promotion for athletes.
5. Why are athletes more likely to experience hyponatremia despite adequate fluid intake during physical activity?
6. Explain how pre-game and post-game meals for athletes facilitate energy utilization.
Answer Key
1. Any activity event outside of those necessary to maintain one’s activities of daily living would lead to improved
power.
2. With regard to physical activity, one would anticipate that the heart rate would increase proportionally to the
intensity and duration of the activity. Increases in target heart rate should be achieved in order for the exercise
3. The body’s response to physical activity is based on the type and duration of the event. Events that require
quick onset of action but are of a limited duration are primarily fueled by different mechanisms as opposed to
longer-duration events. Additionally, the intensity of the event influences the type of fuel utilization by the
4. An athletic lifestyle warrants that individuals should do their best to maintain adequate health and well-being.
Towards that goal, many athletes take vitamin E and iron supplements. Vitamin E supplements are indicated for
5. In addition to water loss, athletes can experience electrolyte losses through sweat during endurance activities,
and environmental conditions may further contribute to fluid and electrolyte losses. If the environment is warm,
6. Pre-game meals are designed to help athletes get the most energy value from food intake. Increased fluid
content with high-carbohydrate food sources in a timeframe of three to four hours prior to competition is
IM Worksheet Answer Key
Worksheet 14-1: Fitness Review (Internet Exercise)
Worksheet 14-2: Physical Activity Self-Evaluation – Answers will vary.
Worksheet 14-3: Cardiorespiratory Endurance Calculation
1. MHR = 220 – 15 = 205, THRR: 205 0.6 = 123 and 205 0.85 = 174.25
Worksheet 14-4: Chapter 14 Crossword Puzzle
1. A: carbohydrate loading;
3. physically fit
6. resistance training
9. fat
257
Worksheet 14-1: Fitness Review (Internet Exercise)
1. The American College of Sports Medicine and the American Heart Association recommend that
healthy adults get a minimum of 60 minutes of moderate-intensity aerobic activity on five days each
week, or get a minimum of 20 minutes of vigorous-intensity aerobic activity on five days of the week.
a. True
b. False
2. Which of the following is NOT a benefit of regular physical activity?
3. According to CDC research findings obtained in 2001, the estimated direct medical cost of
4. Any type of physical activity that meets the criteria of the “talk test” without a corresponding increase
5. Research has shown that swimming exercises substantially reduce the chance of developing heart
disease, stroke, and diabetes in different populations.
a. True
b. False
6. 30 minutes of moderate-intensity aerobic activity a day is the optimal level that one should seek to
7. The Borg scale can be used to evaluate one’s perception of how hard one is exercising.
8. One benefit of strength training is that it increases lean body mass.
a. True
b. False
258
Worksheet 14-2: Physical Activity Self-Evaluation
Fitness depends on a certain minimum amount of physical activity. Ideally, the quantity and quality of the physical
activity you select will improve your cardiorespiratory endurance, body composition, strength, and flexibility.
Examine your activity choices by keeping an activity diary for one week. For each physical activity, be sure to
record the type of activity, the level of intensity, and the duration. In addition, record the times and places of
beverage consumption and the types and amounts of beverages consumed. Now compare the choices you made in
your one-week activity diary to the guidelines for physical fitness.
1. How often were you engaged in aerobic activity to improve cardiorespiratory endurance? Was the intensity of
aerobic activity moderate or vigorous? Did the duration for each session last at least 20 minutes?
5. What changes could you make to improve your fitness?
259
Worksheet 14-3: Cardiorespiratory Endurance Calculations
For each of the individuals below calculate the maximum heart rate (MHR) and the target heart rate range (THRR).
Individual
Maximum Heart Rate
Target Heart Rate Range
15 year old
22 year old
12 year old
80 year old
30 year old
18 year old
45 year old
33 year old
65 year old
260
Worksheet 14-4: Chapter 14 Crossword Puzzle
1
2
3
4
5
6
7
8
9
10
11
Across:
Down:
2. Although most exercisers don’t need them, _____
4. Reflects gains in muscle size and strength as a result
of regular physical activity
10. Diets high in _____ are recommended for all
athletes.
11. Collectively refers to supplements that claim to
enhance athletic performance
3. Enhanced immunity, improved sleep, lower body
5. The only nutrient athletes may need to take in
supplemental form
8. Short-duration, high-intensity activities rely
primarily on _____ for fuel.
9. Low- or moderate-intensity activities with longer
duration rely primarily on _____ for fuel.
261
Handout 14-1: Delivery of Oxygen by the Heart and Lungs to the Muscles
The cardiorespiratory system responds to the muscles’ demand for oxygen by building up its capacity to
deliver oxygen. Researchers can measure cardiorespiratory fitness by measuring the maximum amount of
oxygen a person consumes per minute while working out, a measure called VO2max.
262
Handout 14-2: How to Maximize Glycogen Stores
Through Carbohydrate Loading
Some athletes use a technique called carbohydrate loading to maximize their muscle glycogen stores
before a competition. Carbohydrate loading can nearly double muscle glycogen concentrations. In
general, the athlete tapers training during the week before the competition and then eats a high-
carbohydrate diet during the three days just prior to the event. a Specifically, the athlete follows the plan
in the accompanying table.
Extra glycogen gained through carbohydrate loading can benefit an athlete who must keep going for 90
minutes or longer. Those who exercise for shorter times simply need a regular high-carbohydrate diet. In
a hot climate, extra glycogen confers an additional advantage: as glycogen breaks down, it releases water,
which helps to meet the athlete’s fluid needs.
Before the
Event
Training Intensity
Training
Duration
Dietary Carbohydrate
263
Handout 14-3: Selected Sports Drinks Compared
Beverage
Serving
Size
Energy
(kCal)
Na a
(mg)
K a
(mg)
Mg a
(mg)
Carb
(g)
Fat
(g)
Pro
(g)
Carbohydrate Source
%
Carb
Lactic Acid
Buffer
1st Endurance EFS
12 oz
96
270
160
150
24
0
0
Complex, sucrose, dextrose
7%
None
Accelerade
12 oz
120
190
65
120
21
1
5
Sucrose, trehalose, fructose,
maltodextrin
6%
None
AdvoCare Rehydrate
8 oz
50
100
100
40
12
0
0
Maltodextrin, fructose,
dextrose
5%
None
CarbBoom
160
50
15
17
0
0
Maltodextrin, sucrose,
glucose, fructose
7%
None
Clif Shot Electrolyte
16 oz
200
50
19
0
0
Brown rice syrup solids,
evaporated cane juice
4%
None
Cytomax
16 oz
120
60
14
22
0
0
Amylopectin, maltodextrin,
fructose, dextrose
5%
PolyLactate
eLoad
16 oz
370
97
13
27
0
0
Dextrose, sucrose
6%
MultiCitrate
Enervit G Sport
113
23
14
0
0
Fructose, maltodextrin,
glucose, sucrose
6%
None
Gatorade
110
30
14
0
0
Glucose, sucrose, fructose
6%
None
Gatorade Endurance
200
90
14
0
0
Glucose, sucrose, fructose
6%
None
Gleukos
40
175
17
0
0
Glucose
7%
None
GU20
16 oz
240
40
26
0
0
Maltodextrin, fructose
6%
None
Hammer Nutrition Heed
16 oz
39
16
16
25
0
0
Maltodextrin
6%
L-carnosine
Powerade
52
32
15
0
0
High-fructose corn syrup
7%
None
dextrose
Puresport
16 oz
330
140
140
16
0
6
Dextrose, maltodextrin,
fructose
4%
None
Ultima
38
75
12
0
0
Maltodextrin
1%
None
264
Handout 14-4: Substances Promoted as Ergogenic Aids
Dietary Supplement
Claims
Research Findings
Risks
Arginine (an amino acid)
Increases muscle mass
Ineffective
Generally well tolerated; may be harmful to people with heart disease
Boron (trace mineral)
Increases muscle mass
Ineffective
No adverse effects reported with doses up to 10 mg/day; should be
avoided by those with kidney disease or women with hormone-sensitive
conditions
Coenzyme Q10 (carrier in the
electron transport chain)
Enhances exercise performance
Ineffective
Mild indigestion
Gamma-oryzanol (plant sterol)
Increases muscle mass; mimics
anabolic steroids without known
Ineffective
No adverse effects reported with short-term use; no long-term safety
studies
side effects
and diarrhea; those with diabetes should be aware of hypoglycemic
effects; should be avoided by those at risk for estrogen-related cancers,
those with blood clotting issues, and pregnant or lactating women
exercise performance
betamethylbutyrate; a metabolite
of the branched-chain amino acid
leucine)
strength
body weight
Pyruvate (a 3-carbon sugar)
Enhances exercise endurance
Ineffective
No long-term safety studies; digestive problems with short-term use (<6
weeks)
Ribose (a 5-carbon sugar)
Increases ATP production and
enhances high-intensity exercise
performance
Ineffective
Naturally generated in body; submitted to USDA to become a
Generally Recognized As Safe food additive (pending)
Royal jelly (produced by bees)
Enhances stamina and reduces
fatigue
No studies on human beings to
date
No adverse effects with doses up to 12 mg/day; should be avoided by
those with a history of asthma or allergic reactions
soda)
fatigue; enhances power and
strength
muscle fatigue; more research
is needed for definitive
conclusions
should be avoided by those on sodium-restricted diets
265
Handout 14-5: Side Effects and Adverse Reactions for Anabolic Steroids
Mind
• Extreme aggression with hostility (“steroid rage”); mood swings; anxiety; dizziness; drowsiness;
unpredictability; insomnia; psychotic depression; personality changes; suicidal thoughts
Heart
• Heart disease; elevated or reduced heart rate; heart attack; stroke; hypertension; increased LDL;
reduced HDL
Abdominal Organs
• Nausea; vomiting; bloody diarrhea; pain; edema; liver tumors (possibly cancerous); liver damage,
disease, or rupture leading to fatal liver failure; kidney stones and damage; gallstones; frequent
urination; possible rupture of aneurysm or hemorrhage
Blood
• Blood clots; high risk of blood poisoning; those who share needles risk contracting HIV (the AIDS
virus) or other disease-causing organisms; septic shock (from injections)