Athletic Performance Nutrition Exam 1 Flashcards
1
Q
How many different atoms or chemical elements have been identified in nature?
A
118
2
Q
What is the makeup of the human organism?
A
3% nitrogen
10% hydrogen
18% carbon
65% oxygen
3
Q
What is chemical bonding?
A
A common sharing of electrons between atoms
4
Q
How do atoms in a chain keep their specific form?
A
Chemical bonding
5
Q
What are the four categories of carbohydrates?
A
Monosaccharides
Disaccharides
Oligosaccharides
Polysaccharides
6
Q
What is the main source of carbs in the human diet?
A
Plants
7
Q
What atoms are carbohydrates made of?
A
Carbon
H2O
8
Q
What two nutrients don’t contain carbon?
A
Water
Minerals
9
Q
Almost all substances in the body consist of what compounds?
A
Carbon-containing organic compounds
10
Q
What is a monosaccharide?
A
It is the basic unit of carbohydrates.
11
Q
How many monosaccharides exist in nature?
A
200
12
Q
What does the Greek ending -ose represent?
A
Sugars
13
Q
What are the 3, 6-carbon (hexose) sugars that make up the nutritionally important (examples of) monosaccharides?
A
Glucose
Fructose
Galactose
14
Q
Which sugar naturally occurs in food?
A
Glucose also called dextrose or blood sugar
15
Q
What process do animals use to produce glucose?
A
Gluconeogenesis
16
Q
What is gluconeogenesis?
A
It is the creation of sugar from non-carbohydrates.
Ex: protein into glucose
17
Q
Where is glucose absorbed?
A
Small intestines
18
Q
What are the 3 functions of glucose when it’s absorbed in the small intestines?
A
- Used directly by cells for energy
- Stored as glycogen in muscles & liver for future use
- Converted to lipid & stored for energy
19
Q
In the liver, what is synthesized via gluconeogenesis to produce glucose?
A
Carbon skeletons of specific amino acids
Glycerol
Pyruvate
Lactate
20
Q
Which is the sweetest of the simple sugars?
A
Fructose also called levulose or fruit sugar
21
Q
Where does fructose occur in large amounts?
A
Fruits and Honey
22
Q
How much of the average energy intake in the US does honey account for?
A
9%
23
Q
Does galactose occur freely in nature?
A
No
24
Q
What does galactose form and where is this found?
A
It forms milk sugar or lactose & is found in the mammary glands of lactating animals.
25
What is a disaccharide?
Two monosaccharides
26
What chemical process forms disaccharides?
Dehydration synthesis
27
What are mono- & disaccharides known as?
Simple sugars
28
What are the names of the simple sugars?
Glucose
Fructose
Galactose
Sucrose
Maltose
Lactose
29
What are the 3 (examples of) disaccharides of nutritional significance?
Sucrose
Lactose
Maltose
30
What is sucrose composed of?
Glucose and Fructose
31
What is the most common dietary disaccharide?
Sucrose
32
What part of the total caloric intake in the US does sucrose constitute?
25%
33
What are foods that (examples of) sucrose naturally occurs in?
Beet sugar
Cane sugar
Brown sugar
Sorghum
Maple syrup
Honey
34
Does honey give an advantage nutritionally or as an energy source?
No
35
What is lactose composed of?
Glucose and Galactose
36
What is the only place lactose is found in natural form?
Milk sugar
37
Can lactose be artificially processed?
Yes
38
Which is the least sweet of the disaccharides?
Lactose
39
What is lactose intolerant?
Lacking adequate quantities of the enzyme lactase (small intestine) that splits lactose during digestion.
40
What are foods that contain (examples of) lactose?
Ice cream
Creams
Cheese
Butter
Chocolate varieties
41
What is maltose composed of?
2 Glucose molecules
42
What foods is (examples of) maltose in?
Beer
Cereals
Germinating seeds
43
What is another name for maltose?
Malt sugar
44
What are oligosaccharides?
3-9 monosaccharides that combine
45
What foods are (examples of) oligosaccharides found in?
Vegetables
Seed legumes
- peas
- beans (kidney, navy, pinto, Lima, garbanzo, mung)
- peanuts
- lentils
46
How many carbs should be in total daily caloric intake?
With regular physical activity: 60% (400-600g)
With moderate/intense training: increase to 70% in energy balance
47
How does Type 2 Diabetes occur?
It occurs when the pancreas fails to produce sufficient insulin to regulate blood glucose.
48
When are carbs used as the primary energy source?
During intense physical activity
49
When are glycogen reserves depleted?
1. Starvation and semistarvation
2. reduced energy intake and low-carb diets
3. prolonged strenuous physical activity
50
What is hypoglycemia?
Abnormally reduced blood sugar
51
What are saturated fatty acids made of?
Single covalent bonds between carbon atoms.
52
Examples of monounsaturated fatty acid
- canola oil
- olive oil
- almonds
- pecans
- avocados
53
How many saturated fats are consumed by Americans every year?
50 pounds, or 15% of total caloric intake daily.
54
How much saturated fats should the average young adult male consume?
No more than 10% of total energy intake
Or 250 kcal
Or 25-30 g/d
Or less than 30% of total caloric intake
55
How does fish act as a thrombogenic agent?
1. Prevents blood clot formation on arterial walls
2. Inhibits atherosclerotic plaque growth
3. Reduces pulse pressure & total vascular resistance (inc. arterial compliance)
4. Stimulates endothelial-derived nitric oxide to facilitate myocardial perfusion
5. Lowers triacylglycerol, which may protect against coronary heart disease risk
56
What are phospholipids?
Contains one or more fatty acid molecules combined with a phosphorus-containing group and a nitrogenous base.
57
What functions do phospholipids accomplish when interacting with water?
1. Modulate fluid movement across cell membranes
2. Maintain the cell's structural integrity
3. Play an important role in blood clotting
4. Provide structural integrity to the insulating sheath surrounding nerve fibers
58
What are the 3 factors that impact serum LDL concentration?
1. Regular aerobic physical activity
2. Visceral fat accumulation
3. Diet’s macronutrient composition
59
What functions do lipids serve in the body?
1. Energy source & reserve
2. Vital organ protection
3. Promote thermal insulation
4. Transport medium for fat-soluble vitamins
5. Hunger suppressor
60
What common foods have histidine?
Breast milk, soybeans, fish, chicken breast, beef, wheat germ
61
What common foods have Leucine?
Egg whites, soy, seaweed, spirulina
62
What common foods have Lysine?
Chicken, turkey, tuna
63
What common foods have Isoleucine?
Egg whites, soy, seaweed, spirulina, turkey
64
What common foods have Methionine?
Egg white, fish, chicken
65
What common foods have Phenylalanine?
Pork, beef, lamb, veal, fish
66
What common foods have Threonine?
Watercress, seaweed, spirulina, game meat, turkey, fish
67
What common foods have Tryptophan?
Fatty fish, game meat, seaweed, spirulina, soy protein isolate, spinach, egg white
68
What common foods have Valine?
Egg whites, game meat, seaweed, spirulina, soy protein isolate, watercress
69
What is the recommended protein intake for the average adult?
0.8 grams/kg of body weight
70
Which 3 athlete groups need larger than normal protein intake?
1. Growing and maturing adolescent athletes
2. athletes involved in resistance training and endurance training programs
3. wrestlers, football players, and other sport categories where participants are subjected to recurring muscle trauma
71
What else do amino acids achieve besides synthesizing the building blocks of tissue?
1. incorporate nitrogen into RNA and DNA compounds
2. incorporate nitrogen into the coenzyme electron carriers NAD and FAD
3. Incorporate nitrogen into the game components of the oxygen-building hemoglobin and myoglobin compounds
4. Incorporate nitrogen into the catecholamine hormones epinephrine and norepinephrine
72
What happens to deaminated carbon compounds that are not excreted by the kidneys?
1. Synthesized to a new amino acid
2. Converted to carb or lipid
3. Catabolized directly for energy
73
What is nitrogen balance?
When nitrogen intake from protein equals nitrogen excretion.
74
How much of the total physical activity energy requirement does the alanine-glucose cycle generate during prolonged physical activity?
10-15%
75
How do sugars vary in sweetness?
On a per gram basis
76
What was added to sailor's diet to stop scurvy, and why was it added?
Lemons and limes, and because they possess vitamin C
77
Why are vitamins considered accessory nutrients?
They serve as catalysts to break down energy
78
What is a provitamin? What is an example?
Vitamin A and D. Carotenes
79
What are the two categories of vitamins?
Water-soluble and Fat-soluble
80
What are the water-soluble vitamins?
Vitamin C, B-complex vitamins
81
What are the fat-soluble vitamins?
Vitamins A, D, E, and K
82
What can Hypervitaminosis A, (vitamin A toxicity), causes what?
1. Nervous System irritability
2. Bone swelling
3. Weight loss
4. Dry, itchy skin
5. Nausea
6. Drowsiness
7. Hair loss
8. Diarrhea
9. Bone calcium loss leading to osteoporosis and increased fx risk
83
Dietary Sources of fat-soluble vitamins
Table 2.1, pg. 50
84
Dietary Sources of water-soluble vitamins
1. Folate
2. Vit C
3. Vit B1
4. Vit B2
5. Vit B3
6. Vit B5
7. Vit B6
8. Vit B7
9. Vit B12
85
What are the vitamins in the B-complex?
1. Vitamin B1 (thiamin)
2. Vitamin B2 (riboflavin)
3. Vitamin B3 (niacin-cicotinic acid)
4. Vitamin B5 (prnothenic acid)
5. Vitamin B6 (pyridoxine)
6. Vitamin B7 (biotin)
7. Vitamin B12 (cobalamin)
86
Why don't vitamin needs of the physically active exceed those with sedentary lifestyles?
Because vitamins are mainly used in metabolic reactions
87
What does DRI stand for?
Dietary Reference Intakes
88
What are RDAs?
1. EAR
2. AI
3. UL
89
What does RDA stand for?
Recommended Dietary Allowance
90
What does EAR stand for?
Estimated Average Requirement
91
What does AI stand for?
Adequate Intake
92
What does ESADDI stand for?
Estimated Safe and Adequate Daily Dietary Intakes
93
What do DRI values include?
Gender, life stages of growth and development based on age, pregnancy, and lactation
94
What does EAR include?
Average level of daily nutrient intake to meet the requirement of half of the healthy individuals in a particular life-stage and gender group, and what is an inadequate nutrient intake.
95
What does RDA include?
Represents the average daily nutrient intake level sufficient to meet the requirement of nearly 98% of healthy individuals
96
What does AI include?
Pg 55, bottom right
97
What are the 2015-2020 Dietary Guidelines Recommendations?
1. Limit saturated fat to 10% daily
2. Eat a variety of protein that includes seafood, lean meats, poultry, eggs, soy, legumes, nuts, and seeds
3. Eat fat-free or low-fat dairy, including milk, yogurt, and cheese
4. Consume <10% of calories daily (about 200 kcal) from added sugars
5. Limit alcohol intake to one drink a day for women and two drinks a day for men
6. Limit daily sodium intake <300 mmgs
98
What are the 4 factors that increase the likelihood of promoting oxidative stress?
1. Cellular deterioration associated with advanced aging
2. Cancer, diabetes, coronary artery disease
3. Exercise-related oxidative damage
4. General Decline in central nervous system and immune functions
99
What is the purpose of antioxidant chemicals?
Protect plasma membrane by reacting with and removing free radicals
100
Approximately, what amount of the body's mass is minerals?
4%
101
How many minerals are essentials to life?
7 major minerals and 14 minor minerals
102
How much of the major minerals are required daily?
>100 mg
103
What is a polysaccharide?
The glycosidic bonds linkage of 10-thousands of monosaccharides
104
How much of the minor minerals are required daily?
<100 mg
105
What are the 7 Major Minerals
1. Calcium
2. Phosphorus
3. Potassium
4. Sulfur
5. Sodium
6. Chlorine
7. Magnesium
106
What categories do polysaccharides classify into?
Plant
Animal
107
What are some minor minerals?
1. Iron
2. Fluorine
3. Zinc
4. Copper
5. Selenium
6. Iodine
7. Chromium
108
What are two forms of plant polysaccharides?
Starch
Fiber
109
What foods are calcium found in?
Milk, Cheese, Dark green veg, Dried legumes
110
What foods are phosphorus found in?
Milk, cheese, yogurt, meat, poultry, grains, fish
111
What food is potassium found in?
pg. 64
112
What 3 roles do minerals serve?
pg. 64
113
What 4 factors affect mineral bioavailability?
1. Food type
2. Mineral-mineral iteraction
3. Vitamin-mineral interaction
4. Fiber-mineral interaction
114
Why does food type affect mineral bioavailability?
Foods from the animal contain a high mineral concentration, and the small intestine absorbs it better if plant binders are available
115
Why does mineral-mineral interaction affect mineral bioavailability?
When trying to absorb more than one mineral at a time, they can effect the absorption rate of each other due to molecular weight
116
vitamin-mineral interaction
pg 67
117
Fibre-mineral interaction
pg 67
118
What is a key proposition in exercise and nutritional sciences?
Food sources in a well-balance diet provide all the body's mineral requirements
119
What are the 6 important functions of ionized calcium?
1. Muscle action
2. Blood clotting
3. Nerve impulse transmission
4. Enzyme activation
5. Synthesis of calciferol
6. Fluid transport across cell membranes
120
What are osteoclasts?
They perform bone breakdown/reabsorption
121
What are osteoblasts?
They synthesize bone
122
How much calcium do children between 1-3 require?
700 milligrams
123
How much calcium do women 51+ require?
1200 milligrams
124
How much calcium do men 50-70 require?
1000 milligrams / 4-5 glasses of 8 ounces of milk
125
Which athletes are more prone to calcium dietary insufficiency?
Female dancers, gymnasts, and endurance athletes
126
Children and adults require the same amount of calcium per unit body mass - T/F?
False, kids require more than adults, but many adults have calcium deficiency
127
What 2 things does prolonged calcium imbalance cause?
1. Osteopenia
2. Osteoporosis
128
What is osteopenia?
A midway condition of depletion as bones weaken with increased fracture risk
129
What is osteoporosis?
Bone density values more than 2.5 SD below normal for the age and sex of the young, non-Hispanic white female reference group, with significantly increased fracture risk
130
What are the 2 types of bones?
1. Cortical bone (compact bone)
2. Trabecular bone (cancellous)
131
What is cortical bone?
Dense, hard outer layer bone (e.g., shafts of the arm and leg, long bones)
132
What is trabecular bone?
Spongy, less dense, and relatively weaker bone most prevalent in the vertebrae and ball of the femur
133
When can calcium deficiency begin?
Calcium deficiency can begin at an early age; inadequate dietary calcium affects about 50% of American children under age 5, 65% of teen boys, and 85% of teen girls
134
What is hypercalcemia?
higher than normal blood calcium concentration
135
What is hypocalcemia?
lower than normal blood calcium concentration
136
How many people suffer from osteopenia and osteoporosis?
~ 200 million
137
What percentage of postmenopausal women in the USA and Europe have osteoporosis? Why?
~ 30%
This is due to the absence of estrogen release of the ovaries
138
What percentage of genetics and lifestyle contribute to osteoporosis?
60-80% Genetics
20-40% lifestyle
139
How much bone loss does a man lose annually? How much does a women?
After 50, men loses aboutt 0.4% of bone yearly.
Women lose twice this amount by the age 35
140
How much calcium does calcium carbonate contain?
40% per dose
141
How much calcium does calcium citrate contain?
21% per dose
142
How much calcium does calcium gluconate contain?
9% per dose
143
What is the upper level of calcium intake per day?
2500 milligrams per day
144
What happens if someone exceeds the upper limit of calcium intake?
The risk of kidney stones increases dramatically
145
How can someone of any age or gender build bone?
Moderate-intense weight-bearing aerobic physical activity
146
What happens to athletes bones during and after seasons?
During season, the bone density increases. During off season, it decreases.
147
What is phosphorus used for?
It combines with calcium to give rigidity to teeth and bones
148
pg 80-81
too much, too fast
149
What are the ten common symptoms of iron deficiency anemia?
1. Persistent fatigue
2. Pale colour or having yellow, sallow skin
3. Shortness of breath or chest pain
4. Unexplained generalized weakness
5. Rapid heartbeat
6. Pounding or "whooshing" in the ears
7. Headache brought on with increased physical activity
8. Compulsive craving for ice, freezer frost, or iced drinks, or strong urge to eat nonfoods like paper or clay (picophagia)
9. Sore or smooth tongue
10. Brittle nails or hair loss
150
Which plasma levels reflect the adequacy of current iron intake?
Transferrin
151
What causes an iron absorption decrease?
1. Phytic acid (dietary fibre)
2. Oxalic acid
3. Polyphenols (tea/coffee)
4. Excess of other minerals (Zn, Mg, Ca)
5. Reduced stomach
6. Antacid use
152
What 3 factors are needed to absorb 15% of ingested iron?
1. Iron status
2. Form of ingested iron
3. Meal composition
153
What causes an iron absorption increase?
1. Stomach acid
2. Dietary iron in heme form
3. High body demand for red blood cells (blood loss, high-altitude exposure, exercise training, pregnancy)
4. Presence of meat protein factor
5. Vitamin C in small intestine
154
What are sources of heme iron?
1. Tuna
2. Chicken
3. Clams
4. Beef
5. Oysters
6. Beef liver
155
What are sources of nonheme iron?
1. Oatmeal
2. Spinach
3. Soy protein
4. Dried figs
5. Beans
6. Raisins
7. Lima benas
8. Prune juice
9. Peaches
11. Apricots
156
Iron Status: a concern to some female vegans
The relatively low bioavailability of nonheme iron places women who consume plant-based diets at increased risk for developing iron insufficiency
157
What is sports anemia?
Describes reduced Hb levels approaching clinical anemia attributable to intense training
158
What is foot-strike hemolysis?
Iron loss from sweat and Hb destruction from increased temperature, spleen activity, circulation rates, and mechanical trauma due to runners intense training
159
Athletes and pseudoanemia
pg 84
160
Excess iron intake may augment latent cancer growth and infectious pathogenic organisms - T/F
True
161
What does a starch serve as?
The storage form of carbs & the most familiar form of plant polysaccharide
162
How much of daily total carb intake in the American diet does plant starch account for?
50% of total carb intake
163
What does complex carb refer to?
Dietary starch
164
What foods are starches plentiful in?
Seeds
Corn
Grains for making (bread, cereal, spaghetti, & pastries)
Peas
Beans
Potatoes
Roots
165
What are the two forms of starch?
Amylose
Amylopectin
166
What is amylose?
A long, straight chain of glucose twisted into a helical coil
Eg: white bread
167
What is amylopectin?
A highly branched monosaccharide linkage
Eg: apple
168
What is fiber?
An “unheralded” nutrient that is a nonstarch structural polysaccharide & includes cellulose
169
What is cellulose?
The most abundant organic molecule on earth
170
Do fibrous materials have nutrients or available calories?
No
171
What do fibrous materials resist?
Hydrolysis by human digestive enzymes
172
What do fibers look like?
They have thick cell walls & elongated cells with tapering ends
173
Do fibers exist exclusively in plants?
Yes
174
What do fibers make up?
Structure of leaves, stems, roots, seeds, & fruit coverings
175
Where is fiber normally located?
Within the cell wall as cellulose, gums, hemicellulose, pectin, non-carb lignins that govern rigidity to plant cell walls
176
What is the biome?
The guts mass of microorganisms consisting of tens of trillions of bacteria
177
What are the 3 main microbe groups?
Bacteroidetes
Firmicutes
Actinobacteria
178
What is the biome’s colony of bacteria essential for and do?
Facilitate food digestion and optimal food processing
179
What is gut bacteria called?
“Digestive hitchhikers”
180
What is the western diet high in?
Fiber-free animal foods
181
What is the western diet low in?
Natural plant fibers lost through the refining process
182
What does the western diet contribute to?
More intestinal disorders compared to countries that consume a diet high in unrefined, complex carbs
183
What is the typical American diet fiber intake compared to African or Indian diets?
12-15g compared to 40-150g daily
184
Dietary fiber may aid GI functions in what 3 ways?
1. Exerts a scraping action on the cells of the gut wall
2. Binds or dilutes harmful chemicals or inhibits their activity
3. Shortens transit time for food residues (& possibly carcinogenic materials) to pass through the digestive tract
185
What is the result of fiber retaining considerable water?
-Gives “bulk” to food residues in large intestines
-Increases stool weight & volume by 40-100%
186
What is the recommended daily fiber intake?
Women: 19-50 is 25g
Men: 19-50 is 38 g
187
What do prebiotics do?
Feed the gut bacteria that keep the colon healthy
188
What are water-soluble fibers?
Mucilaginous pectin & guar gum fibers (oats, rolled oats, oat bran, oat flour)
Legumes
Barley
Brown rice
Peas
Carrots
Psyllium
Various fruits (rich in phytochemicals & antioxidants)
189
What are phytochemicals?
190
What are antioxidants?
191
Where are water-insoluble fibers found?
Wheat bran
Whole wheat products
192
Which type of fiber lowers cholesterol?
Water-soluble fibers
193
What is the optimal strategy for obtaining diverse fibers?
From food in the daily diet, not from fiber supplements.
194
Look at table 1.1
195
What is the general guideline for recommended fiber intake?
14g daily per 1000 kcal consumed
- 25g for women
38g for men
196
What is glycogen?
The storage polysaccharide found in mammalian muscle and liver
197
What are electrolytes?
Sodium, potassium, and collectively
198
What is hypokalemia?
Potassium deficiency
199
What do electrolytes do?
Modulate fluid exchange within the body's fluid compartments, allowing exchange of nutrients and waste products. Also, maintains plasma membrane permeability naff regulates acid and base qualities of body fluids
200
What are the benefits of adequate potassium intake?
Counters high blood pressure by making the larger blood vessels more flexible, while the smaller vessels are dilated to reduce peripheral resistance
201
When do suboptimal Hb concentrations & hematocrits occur more frequently?
Endurance athletes (this supports possibility of exercise-induced anemia)
202
What is the most important function of potassium and sodium?
They are able to establish the ideal electrical gradient across cell membranes by way of the Na+/K+ pumps
203
What does excess iron intake augment?
Latent cancer growth & infectious microbial pathogenic organisms
204
What steroid hormone is used with low-moderate sodium intake? Where does it come from?
Aldosterone, and it is synthesized from cholesterol within the adrenal glands
205
What medical complications will occur from toxic levels of excessive iron?
Complications from diabetes, liver disease, heart & joint damage
206
What is the cut off for Hb levels for clinical anemia?
Pg 84
207
What are diuretics used for?
A drug used to induce water-loss to help lower blood pressure. Also produces losses in other minerals, like potassium
208
What are the 4 health benefits to consuming enough sodium? pg 88
1. Prevent up to 92.000 deaths and 66,000 strokes yearly
2. Prevent nearly 100,000 Americans from having a heart attack and nearly 120,000 others form acquiring heart disease yearly.
3.
4.
209
What are antihypertensives?
What do antihypertensives do?
Drugs that interfere with aldosterone action
They reduce blood pressure by blocking ACE which leads to lower Aldosterone secretion & action
210
What does ACE stand for?
Angiotensin-converting enzyme
211
What influences individual water content?
Age, gender, and body composition
212
How many Americans have hypertension?
Nearly 50 million
213
How much weight does water account for on average?
40-70% of body mass
72% of muscle weight
20-50% of body fat/adipose tissue
214
pg 89
215
Why is carb-loading a double-edge sword?
additional water storage decreases exercise economy because extra body weight increases energy expenditure
216
What is glycogen's purpose with water?
A glycogen gram joins with 2.7 grams of water as the glucose units link together, thus making glycogen a heavy-energy fuel, and then releases it during catabolism
217
What are the 6 types of intracellular fluid?
1. Lymph
2. Saliva
3. Eye fluid
4. Fluids secreted by glands & the digestive tract
5. Clear fluid that bathes the brain & spinal cord nerves (cerebrospinal fluid)
Fluids excreted from skin (water & sweat) & kidneys (filtered fluids & urine)
Pg. 90
218
How much water loss can occur during vomiting or diarrhea?
between 1500 and 5000 millilitres
219
What 6 crucial bodily functions does water serve?
Pg. 90
220
What are the 3 factors that determine water loss through sweat?
1. Severity of physical activity
2. Environmental temperature
3. Relative humidity
221
How does water lose water?
1. In urine
2. Through skin
3. As water vapor in air
4. In feces
222
What is the major physiologic defence against overheating?
Evaporation of sweat from the skin's surface
223
What is relative humidity?
Water content of ambient air compared with what the air can contain at that temperature, which impacts the efficiency of the sweating mechanism in temperature regulation
224
What is insensible perspiration?
When the skin emits water through skin pores at night at considerably reduced rates
225
When is the ambient air fully saturated with water vapour?
100% of relative humidity
226
What happens at 100% of relative humidity?
This blocks fluid evaporation from the skin surface to air, minimizing an important avenue for body cooling. This is when sweat beads on the skin and eventually rolls off without generating a cooling effect
227
What is the sweat rate under normal non-sleeping conditions?
500-700 ml
228
What are the 4 hormones that regulate digestion?
1. Gastrin
2. Secretin
3. Cholecystokinin
4. Gastric Inhibitory Peptide
229
What is the salivary glands target organ, secretion, and action?
TO: mouth
S: saliva
A: breaks down carbs
229
Where does gastrin originate, secretion stimulus, and what's its action?
1. Pyloric areas of stomach and upper duodenum
2. Food in stomach; nerve input to spinster, slows gastric emptying
3. Stimuluates flow of stomach enzymes and acid; stimulates lower esophagus
230
Where does GIP originate, secretion stimulus, and what's its action?
1. Duodenum, jejunum
2. Lipids; proteins
3. Inhibits secretion of stomach
231
What is the gastric glands target organ, secretion, and action?
TO: stomach
S: gastric juice
A: mixes with food bolus, hydrochloric acid & enzymes degrade proteins
232
What is the Pancreas target organ, secretion, and action?
TO: small intestine
S: pancreatic juice
A: bicarbonate neutralizes acidic gastric juices, pancreatic enzymes degrade carbs, lipids, & proteins
233
What is the livers target organ, secretion, and action?
TO: gallbladder
S: bile
A: stored until needed
234
Where does CCK originate, secretion stimulus, and what's its action?
pg. 98
235
What is the gallbladders target organ, secretion, and action?
TO: small intestine
S: bile
A:
236
pg 102
237
What is the GI tract?
Consists of a 7- to 9-metre-long tubular passage that runs from the mouth to the anus; supplies body with water and nutrients
238
What is a sphincter?
A circular muscle arrangement acting as a one way valve & regulates the flow of material through the GI tract
239
What does the mouth do?
Mixes food with saliva
240
What does the esophagus do?
Passes food to stomach
241
What do the salivary glands do?
Secret saliva that contains starch-digesting enzymes
242
Table 3.3 on pg 105, know name, location, and what it does
243
What does the cardiac sphincter do?
Allows passage from esophagus to stomach. Prevents back flow from stomach
244
What does the liver do?
Manufactures bile, a detergent-like substance to digest lipids
245
What does the stomach do?
Adds acid, enzymes, and fluid. Churns, mixes, and grinds food to a liquid mass
246
What does the pyloric sphincter do?
Allows passage from stomach to small intestine. Prevents back flow from small intestine
247
Where is the esophageal sphincter located?
At the junction between the esophagus & stomach
248
What does the gallbladder do?
Stores bile until needed
249
What does the bile duct do?
Conducts bile into the small intestine
250
What does the esophageal sphincter do?
Prevents back flow (reflux) of stomach contents into the esophagus
- it only opens when the esophageal muscles contract
251
What does the ileocecal valve (sphincter) do?
Allows passage from small to large intestine. Prevents back flow form large intestine
252
What does the pancreas do?
Manufactures enzymes to digest food and bicarbonate to neutralize stomach acid
253
Where is the pyloric sphincter located?
At the junction between the stomach & first part of the intestine
254
What does the pancreatic duct do?
Conducts pancreatic juice into small intestine
255
What does the pyloric sphincter do?
It is under hormonal & nervous system control & prevents back flow of intestinal contents into the stomach
256
What does the small intestine do?
Secretes enzymes that digest all food to small nutrient particles. Cells absorb nutrients into blood and lymph
257
What does the large intestine (colon) do?
Reabsorbs water and minerals. Passes undigested waste (fibre, bacteria, and some water) to rectum
258
Where is the oddi sphincter located?
At the end of the common bile duct
259
What does the appendix do?
No digestive function
260
What does the rectum do?
Stores waste prior to elimination
261
Where is the ileocecal sphincter located?
Terminus of the small intestine
262
What does the anus do?
Holds rectum closed
263
Where does 90% of the digestion occur in the small intestine?
The first two sections, also know as the small bowel
264
Where is the anal sphincter located?
265
What are the three parts of the first section of the small intestine?
1. Jejunum
2. Ileum
3. pg 105
266
What does the pancreas secrete? How much?
1. Alkali-containing juice which helps buffer the stomach's hydrochloric acid remaining in the intestinal chyme
2. ~1.2 and 1.6 litres
267
How long does it take after consuming food before the GI tract eliminates its residues?
1-3 days
268
Where are the salivary glands located? What do the salivary glands secrete?
1. The underside of the jaw
2. salivary a-amylase
269
What does the gas flatus consist of?
Hydrogen (H2), nitrogen (N2), methane (CH4), hydrogen sulfide (H2S), & carbon dioxide (CO2)
270
Figure 3.9
271
What may cause excessive flatus?
Consuming large amounts of beans or dairy products
272
How much of the 8-12 liter food volume, fluid, and gastric secretions that enter
Pg 109
273
What is hepatic portal circulation?
regulates circulation transport from the GI tract
274
What breaks down food in the small intestine?
Pancreatic Amylase
275
Where does the major breakdown of lipids occur?
Small intestines, particularly triacylglycerols containing long-chain 12-18 carbon fatty acids
276
Figure 3.10
277
What does CCK regulate in the GI tract?
1. Stomach motility
2. Stomach secretion
3. Gallbladder contraction and bile flow
4. Enzyme secretion by the pancreas
278
What does pepsin breakdown?
Digests protein into short-chain polypeptides
279
What are the 5 objectives of the acidification of ingested food?
1. Activate pepsin
2. Kills pathogenic organisms
3. Improves iron & calcium absorption
4. Inactivates hormones of plant & animal origin
5. Denatures food proteins, making them more vulnerable to enzyme action
280
What controls pepsin?
Gastrin
281
How does vitamin absorption occur?
By diffusion (passively)
282
Where are calcium, magnesium, phosphorus, and trace minerals mainly absorbed?
The small intestine
283
What are the 6 factors of mineral absorption?
1. Bioavailability
2. Transit time from the dietary source to a specific absorptive site
3. Quantity of digestive juices
4. pH of intestinal lumen contents
5. Receptor sites in the intestine’s mucosal lining & brush border
6. Availability of substances that combine with minerals during movement from the gut & across cell membranes
284
Is there variation between the mineral absorption of males and females?
Yes
285
How much calcium do we normally absorb?
Between 25-35%, the other 2/3 is excreted in the feces
286
What does the body’s mineral availability depend on?
It’s chemical form
287
What does the body’s osmosis process in the small intestines determine?
The body’s major strategy to absorb ingested water & water contained in foods
288
Does the continuous water secretion & absorption within the GI tract make it difficult to quantify the body’s net water uptake?
Yes
289
What are two positive GI tract health benefits of a physically active lifestyle?
1. Enhances gut emptying
2. Reduces incidences of liver disease, gallstones, colon disorders, polyps, & constipation
290
What 3 factors help explain activity-related alterations in nutrient & fluid absorption?
1. Mode of physical activity
2. Environmental temperature
3. Type of food/liquid ingested
291
What is constipation?
A delay in stool movement through the colon because the large intestine absorbs excessive water, producing hard, dry stools
292
What is the most common cause of constipation?
Diets high in lipid & low in water & fiber
293
What are the symptoms of diarrhea?
Increased peristalsis, intestinal irritation or damage, medication side effects, intolerance to gluten, & perhaps emotional distress
294
What is gluten?
A protein in some wheat products
295
How much water does the intestinal tract, the small intestine absorb, and the large intestine?
1. 9 Litres
2. 72%
3. 8%
296
What do high incidences of GI distress pg, 117
Interruptions in O2 supply & blood flow including increased parasympathetic nervous system activity during activity
297
What is glucogenesis?
Glucose being synthesized into glycogen
298
What is glycogenolysis?
Glucose formation from glycogen
299
What is the make up of glycogen?
A few 100 to 1000s of glucose molecules linked together like a sausage chain with some branch points for additional glucose linkage
300
What is glucagon?
Insulin’s opposing hormone that stimulates liver glycogenolysis & gluconeogenesis to raise blood glucose concentration
301
What type of glycogen is the major source of carb energy for active muscles during physical activity?
Muscle glycogen
302
What is the body’s upper limit for glycogen storage?
- 15 g/kg of body mass
= 1050g for avg 70kg man
= 840g for avg 56kg woman
303
For a typical 80kg person where are the 500g of carbs stored?
- 400g as muscle glycogen
- 90-110g as liver glycogen
- 2-3g as blood glucose
304
How many kcals of energy is a gram of glycogen or glucose?
4 kcal
305
How much carb energy does the typical person store?
1500-2000 kcal
This is enough to power a high-intensity 20-mile run the length of Manhattan plus another 6 miles of running side streets
306
What stimulates glucose synthesis from other nutrients structural components in the body?
Depleting liver & muscle glycogen through dietary restrictions or intense physical activity
307
How much of the total calories in the typical American diet do carbs account for?
40-50% or
300g daily for a sedentary 70kg person
308
What are the 6 physical activity-related GERD symptoms?
1. Substernal chest pressure
2. Pain or burning that mimics angina
3. Sour taste
4. Eructation (voiding through the mouth of gas or mall quantity of stomach acid fluid)
5. Nausea
6. Vomiting
309
What are the lifestyle changes factors of GERD?
1. Attempting sleep within 4 hrs following an evening meal
2. Postprandial physical activity
3. Excessive food consuption of chocolate, peppermint, onions, high-fat foods, alcohol, tobacco, coffee, and citrus products, which relaxes the lower esophageal sphincter
310
What is diverticulitis?
Small pouches that bulge outward through tissue weak spots that develops on the colon
311
What are the 8 factors that cause IBS?
1. Increased GI motor reactivity to stress
2. Foods high in lipid, insoluble fibre, caffeine, coffee, carbonation, alcohol
3. Dysfunction of the CCK
4. Impaired bowel gas transit
5. Visceral hypersensitivity
6. Impaired reflex control that delays gas transit
7. Autonomic dysfunction
8. Altered immune activation
312
What are the 4 most common IBS symptoms?
1. Cramping abdominal pain relieved by defecation
2. Altered stool frequency
3. Altered stool form
4. Abdominal distension especially following meals
313
What portion of older Americans does diverticulitis affect?
1/2 of all Americans age 60-80 years
Almost everyone older than age 80
314
What is functional dyspepsia?
Chronic pain in the upper abdomen without obvious physical cause
315
What are 4 common methods that provide dietary information?
- 24-hour dietary recall
- food diary
- food frequency assessment
- diet history
316
What does chronic heartburn represent?
A serious disorder called GERD
317
What percentage of athletes experience GERD?
60%
318
Does GERD happen more frequently during physical activity or at rest?
Physical activity
319
What are the 4 lifestyle and dietary modifications that effectively counter IBS?
1. Stress reduction
2. Consuming daily small meals
3. Consuming a high-fibre diet
4. Avoiding foods with lactose and candy that contains sorbitol
320
What is 24-hr Dietary Recall?
Usually a qualitative assessment by the individual or another person that involves informal oral questioning about food and beverage intake in the last 24 hrs
321
What are the 3 most common causes of dyspepsia?
1. Peptic ulcer disease
2. GERD
3. Gastritis
322
What is gastritis?
Inflammation of stomach lining with accompanying pain
323
What is a problem with 24-hr Dietary Recall?
An inaccuracy in quantity assessment and method of food preparation. This frequently produces gross underestimation of hidden lipids in such foods as sauces and dressings
324
How long is a food diary maintained?
2-7 days
325
What is Food Frequency Assessment?
A food frequency questionnaire lists various foods, and the person estimates the frequency of consuming each item
326
Should a food diary include a weekend day?
Yes, because most people eat differently on the weekend than during a typical school/work day?
327
What is Diet History?
It yields general information about a person's dietary patterns. Factors include eating habits (# of meals per day, who prepares meals, and patterns of food preparation), food preferences, eating locations, and typical food choices in different situations
328
Does a combination of methods or one method prove more valid in developing a comprehensive dietary assessment?
A combination of methods
329
What 4 factors is metabolic syndrome characterized by?
1. Disturbed glucose & insulin metabolism
2. Overweight & abdominal fat distribution
3. Mild dyslipidemia
4. Hypertension
330
What 3 goals do diets with fiber-rich low-glycemic carbs accomplish?
1. Lower blood glucose & insulin response following a meal
2. Improve blood lipid profile
3. Increase insulin sensitivity
331
What 4 functions do carbs serve in energy metabolism & exercise performance?
1. Energy source
2. Affects metabolic mixture & spares protein
3. Metabolic primer& prevents ketosis
4. Central nervous system fuel
332
How does the CNS rely on carbs to function optimally?
It relies on blood glucose almost exclusively as it’s fuel
333
What maintains normal blood glucose levels at rest & during physical activity?
Liver glycogenolysis
334
What level is blood glucose maintained at?
100 mg/dL
335
What are examples of simple lipids?
Triglycerides
Beeswax
336
What are examples of compound lipids?
Lecithins, cephalins, lipositols, cerebrosides, gangliosides, chylomicrons, VLDLS, LDLS, HDLS
337
What are examples of derived lipids?
Fatty acids
Steroids
Hydrocarbons
338
What are examples of saturated fatty acids?
Animal beef & lamb (50%)
Pork (40%)
Chicken & egg yolk (36%)
Cream, milk, butter (62%)
Cheese
339
What percent of the diet should lipids not exceed?
30%, 70% of this should be unsaturated fatty acids
340
What is the recommended amount of cholesterol that shouldn’t be exceeded daily?
300 mg or O0.01 oz
