Exam 2 Flashcards
(400 cards)
1
Q
What does direct calorimetry measure?
A
Heat production to determine energy expenditure.
2
Q
What does indirect calorimetry estimate
A
Energy expenditure via oxygen consumption and CO₂ production.
3
Q
What is the purpose of the Haldane transformation?
A
Corrects for differences in expired air volume.
4
Q
How is the respiratory exchange ratio (RER) calculated?
A
CO₂ released divided by O₂ consumed.
5
Q
What does RER indicate?
A
Relative fat vs. carbohydrate utilization.
6
Q
Why is indirect calorimetry inaccurate during nonsteady-state exercise?
A
Oxygen uptake underestimates total energy cost.
7
Q
How does hyperventilation affect RER?
A
It may artificially elevate RER.
8
Q
Why does indirect calorimetry not account for protein oxidation
A
t only considers carbohydrate and fat metabolism.
9
Q
Why does anaerobic energy contribution make indirect calorimetry less accurate?
A
Oxygen uptake underestimates the total energy cost.
10
Q
What isotopes are used to measure energy metabolism?
A
Carbon-13 and doubly labeled water.
11
Q
What does basal metabolic rate (BMR) measure?
A
Energy required for essential physiological functions.
12
Q
What is a more practical measurement than BMR?
A
Resting metabolic rate (RMR).
13
Q
What factors influence BMR?
A
Fat-free mass, surface area, age, temp, stress, hormones.
14
Q
How does exercise intensity affect metabolic rate?
A
Higher intensity increases metabolic rate.
15
Q
What are the two components of oxygen uptake during exercise?
A
Slow and fast phases.
16
Q
What is V̇O₂ drift?
A
Slow increase in oxygen uptake at constant workload.
17
Q
What is the difference between V̇O₂ max and V̇O₂ peak?
A
V̇O₂ max is the true maximal aerobic capacity.
18
Q
Does V̇O₂ max predict endurance performance?
A
No, other factors contribute.
19
Q
What does EPOC stand for?
A
Excess postexercise oxygen consumption.
20
Q
What happens at the lactate threshold?
A
Blood lactate begins rising quickly.
21
Q
How does training affect lactate threshold?
A
it increases with aerobic training.
22
Q
What are some contributing factors to EPOC
A
ATP-PCr restoration, lactate clearance, oxygen storage, body temp.
23
Q
What does economy of effort refer to
A
More efficient movement reduces energy expenditure.
24
Q
What factors influence the energy cost of activity?
A
Exercise type, intensity, duration, age, sex, weight.
25
How is fatigue defined?
Decline in performance with continued effort.
26
What are four primary causes of fatigue?
Energy depletion, metabolite accumulation, contractile failure, neural changes.
27
What happens to PCr levels during intense exercise?
They decrease, contributing to fatigue.
28
How does ATP depletion affect exercise?
Reduces energy availability.
29
How does glycogen depletion relate to fatigue?
Muscle and liver glycogen depletion can cause fatigue.
30
Which muscle fibers deplete glycogen faster
Fast-twitch fibers.
31
What happens to glycogen in different muscle groups?
Active muscles deplete glycogen first.
32
What happens to blood glucose when liver glycogen is depleted?
Blood glucose drops, impairing performance.
33
Why does glycogen depletion impair ATP production?
Less fuel is available for glycolysis.
34
What metabolic by-products contribute to fatigue?
Inorganic phosphate, heat, hydrogen ions.
35
How does inorganic phosphate accumulation cause fatigue?
It disrupts calcium handling in muscles.
36
How does high body temperature affect muscle function?
Impairs metabolism and increases fatigue.
37
Which molecule is often wrongly blamed for fatigue?
Lactate; hydrogen ions are the real culprit.
38
How can neural transmission contribute to fatigue?
Impaired neurotransmitter release affects muscle activation.
39
What role does the central nervous system play in fatigue?
It can limit performance through central fatigue mechanisms.
40
When does acute muscle soreness occur?
During or immediately after exercise.
41
When does delayed-onset muscle soreness (DOMS) occur?
24–48 hours post-exercise.
42
What is the primary cause of DOMS?
Structural muscle damage.
43
What immune response is involved in DOMS?
White blood cell activation and inflammation.
44
What is the sequence of DOMS development
Muscle damage → inflammation → swelling → pain.
45
How does DOMS affect performance?
Reduces strength, power, and coordination.
46
How can DOMS be minimized?
hrough gradual training progression
47
What causes exercise-associated muscle cramps (EAMC)?
Muscle fatigue.
48
What causes heat cramps?
Sodium loss and dehydration.
49
What is one limitation of direct calorimetry?
It is expensive and slow.
50
What is one advantage of indirect calorimetry over direct calorimetry?
It is more practical for measuring exercise metabolism.
51
What is the typical range for RER values?
0.7 to 1.0.
52
What does an RER of 0.7 indicate?
Predominantly fat oxidation.
53
What does an RER of 1.0 indicate?
Predominantly carbohydrate oxidation.
54
Why is RER above 1.0 possible?
Due to hyperventilation and CO₂ buffering.
55
What factors can affect RER accuracy?
Hyperventilation, nonsteady-state exercise, protein oxidation.
56
How does doubly labeled water estimate energy expenditure?
By tracking isotopes in body fluids over time.
57
What is a major advantage of doubly labeled water?
It allows for free-living energy expenditure assessment.
58
What is a drawback of isotopic methods?
High cost and time-consuming analysis.
59
How is resting metabolic rate (RMR) measured?
in a relaxed state, without fasting requirements.
60
What is the largest determinant of RMR?
Fat-free mass.
61
How does aging affect RMR?
RMR decreases with age due to muscle loss.
62
How does body temperature affect metabolic rate?
Higher temperatures increase metabolic rate.
63
How do hormones influence metabolic rate?
thyroid hormones and catecholamines increase it.
64
How does psychological stress affect metabolic rate?
Increases due to elevated sympathetic activity.
65
What is the relationship between exercise intensity and oxygen consumption
Oxygen consumption increases with intensity.
66
What is oxygen deficit?
The difference between oxygen needed and oxygen consumed at exercise onset.
67
What happens to V̇O₂ when transitioning from rest to steady-state exercise?
It gradually increases.
68
What is the relationship between V̇O₂ max and aerobic performance?
Higher V̇O₂ max generally allows for better endurance.
69
What is a limitation of V̇O₂ max?
it does not account for efficiency or lactate threshold.
70
How long does it take for V̇O₂ max to plateau with training?
8–12 weeks.
71
Why does endurance performance continue to improve despite a V̇O₂ max plateau?
Due to increases in lactate threshold.
72
What is a typical range for lactate threshold in untrained individuals?
Around 50–60% of V̇O₂ max.
73
What is a typical lactate threshold in elite endurance athletes?
70–80% of V̇O₂ max.
74
How does the economy of effort impact endurance performance?
A better economy reduces oxygen demand for a given pace.
75
What factors contribute to a better economy of effort?
Technique, muscle fiber type, and biomechanics.
76
What is peripheral fatigue?
Fatigue occurring at the muscle level.
77
What is central fatigue?
Fatigue caused by the central nervous system.
78
Why does PCr depletion contribute to fatigue?
PCr provides rapid ATP resynthesis.
79
When is PCr depletion most significant?
During high-intensity, short-duration exercise.
80
How does glycogen depletion contribute to fatigue?
Less fuel is available for ATP production.
81
Which muscle fibers use glycogen the fastest?
Type II (fast-twitch) fibers.
82
How does glycogen depletion differ between muscle groups?
Active muscles deplete glycogen first.
83
How does glycogen depletion in the liver affect performance?
Blood glucose drops, reducing brain function and muscle performance.
84
What metabolic by-product is strongly associated with fatigue?
Inorganic phosphate (Pi).
85
How does Pi accumulation affect muscle function?
It reduces calcium release, impairing contraction.
86
How does heat accumulation affect performance?
It increases carbohydrate use and accelerates glycogen depletion.
87
Why does dehydration contribute to fatigue?
Reduces plasma volume, decreasing oxygen delivery.
88
What happens to muscle function when body temperature exceeds optimal levels?
Muscle enzyme activity declines.
89
What is the role of hydrogen ions in fatigue?
They lower muscle pH, inhibiting enzyme function.
90
How does neural transmission contribute to fatigue?
Disrupted neurotransmitter release and receptor function impair contraction.
91
What role does the CNS play in limiting performance?
The brain may reduce neural drive to prevent damage.
92
What is the primary cause of acute muscle soreness?
Fluid accumulation and metabolite buildup.
93
What types of exercise commonly cause DOMS?
Eccentric exercises like downhill running and resistance training.
94
What type of muscle fibers are most affected by DOMS?
Fast-twitch (Type II) fibers.
95
What structural damage occurs with DOMS?
Sarcomere and connective tissue disruption.
96
What immune response contributes to DOMS?
White blood cells trigger inflammation.
97
What enzyme is a marker of muscle damage?
Creatine kinase (CK).
98
How does DOMS affect strength
Reduces force production for days after exercise.
99
What are two strategies to reduce DOMS?
Gradual training progression and proper recovery.
100
Why is some muscle damage beneficial?
It stimulates muscle adaptation and growth.
101
What are exercise-associated muscle cramps (EAMC)?
Cramps caused by muscle fatigue.
102
What is a common cause of heat cramps?
Sodium depletion and dehydration.
103
How can heat cramps be prevented?
adequate hydration and electrolyte intake.
104
How can EAMC be relieved?
Stretching and neuromuscular relaxation techniques.
105
What is the relationship between lactate accumulation and fatigue?
Higher lactate levels correlate with increased fatigue.
106
How does endurance training affect glycogen depletion?
Improves glycogen storage and utilization.
107
How does altitude affect energy expenditure?
increases oxygen demand and metabolic rate.
108
How does energy expenditure differ between men and women?
Men generally have a higher expenditure due to greater muscle mass.
109
What is the effect of caffeine on endurance performance?
It may delay fatigue by mobilizing fat stores.
110
How does dehydration impair aerobic performance?
Reduces blood volume, oxygen delivery, and heat dissipation.
111
How does body composition affect resting metabolic rate?
More lean mass increases RMR.
112
How does endurance training affect resting metabolic rate?
It can slightly increase RMR due to muscle maintenance.
113
What role do mitochondria play in energy metabolism?
They produce ATP through oxidative phosphorylation.
114
How does exercise duration impact fuel utilization?
Longer exercise shifts reliance to fat metabolism.
115
Why does carbohydrate consumption before exercise affect RER?
It increases RER, indicating higher carbohydrate oxidation.
116
What is the relationship between EPOC and exercise intensity?
Higher intensity leads to greater EPOC.
117
How does resistance training influence EPOC?
It prolongs post-exercise oxygen consumption due to muscle repair.
118
What happens to energy expenditure during sleep?
it decreases but remains active for essential functions.
119
How does hydration status affect metabolic rate?
Dehydration can lower metabolic efficiency.
120
What effect does altitude have on metabolism?
Higher altitude increases energy expenditure due to oxygen demand.
121
Why do endurance athletes experience ‘hitting the wall’?
Glycogen depletion leads to a reliance on fat metabolism, reducing intensity.
122
What is central governor theory?
the brain limits muscle activation to prevent damage.
123
How does neuromuscular fatigue affect performance?
Impaired signal transmission reduces muscle force output.
124
How do antioxidants influence fatigue?
They may reduce oxidative stress but can also blunt training adaptations.
125
How does acidosis impact muscle function?
it impairs enzyme activity and cross-bridge cycling.
126
What is the primary cause of fatigue in ultra-endurance events?
Glycogen depletion and dehydration.
127
Why do fast-twitch fibers fatigue more quickly than slow-twitch fibers?
They rely more on anaerobic metabolism, which leads to faster metabolite buildup.
128
How does chronic stress affect fatigue?
Increases cortisol levels, impairing recovery and performance.
129
What impact does overtraining have on fatigue levels?
It leads to persistent fatigue and decreased performance.
130
How does sleep deprivation influence fatigue?
It impairs recovery, reaction time, and endurance.
131
What is the repeated bout effect?
Prior eccentric exercise reduces future DOMS.
132
How do foam rolling and massage affect DOMS?
They can improve circulation and reduce soreness.
133
What is the role of compression garments in recovery?
They may reduce swelling and enhance blood flow.
134
How does protein intake aid muscle recovery?
It helps repair muscle fibers and reduce soreness.
135
Why do NSAIDs sometimes hinder muscle recovery?
They can reduce inflammation but may slow adaptation.
136
How does hydration impact muscle soreness?
Proper hydration helps flush metabolic by-products.
137
What is the role of cryotherapy in muscle recovery?
It may reduce inflammation and perceived soreness.
138
How does active recovery aid in reducing soreness?
Low-intensity movement improves circulation and removes waste products.
139
Why is DOMS more common in untrained individuals
They lack the adaptations to withstand eccentric stress.
140
How does stretching before exercise impact soreness?
It does not prevent DOMS but may improve flexibility.
141
How does fatigue contribute to exercise-associated muscle cramps?
It alters neuromuscular control, leading to involuntary contractions.
142
Why does sodium depletion lead to muscle cramping?
It disrupts electrolyte balance, impairing nerve signaling.
143
How does neuromuscular overload contribute to cramps?
High-intensity contractions without proper relaxation can cause spasms.
144
Why are night cramps common in athletes?
Dehydration and electrolyte imbalances accumulate over the day.
145
How does potassium influence muscle cramping
it helps maintain normal nerve and muscle function.
146
Why does pickle juice sometimes relieve cramps?
It triggers a neural reflex that inhibits muscle cramping.
147
How does proper warm-up reduce the risk of cramping?
It prepares muscles for activity and improves circulation.
148
What is the best strategy to prevent muscle cramps
Adequate hydration, electrolyte balance, and proper training progression.
149
How do muscle cramps differ from spasms?
Cramps are prolonged involuntary contractions, while spasms are brief and often painless.
150
What is the effect of magnesium on muscle function?
It plays a role in muscle relaxation and nerve function.
151
How does aerobic training improve fatigue resistance?
It enhances oxygen delivery and mitochondrial function.
152
Why does muscle fiber type impact endurance performance?
Slow-twitch fibers resist fatigue better due to oxidative capacity.
153
How does creatine supplementation influence energy expenditure
It enhances PCr availability, delaying fatigue in short-duration efforts.
154
How does glycogen loading benefit endurance athletes?
it increases stored carbohydrates for prolonged exercise.
155
Why does interval training improve lactate threshold?
It trains the body to tolerate and clear lactate more efficiently.
156
What is the difference between anaerobic and aerobic fatigue?
Anaerobic fatigue is rapid due to metabolite buildup, while aerobic fatigue is gradual due to fuel depletion.
157
Why do highly trained athletes recover faster from exercise?
They have better metabolic efficiency and faster lactate clearance.
158
How does tapering before competition enhance performance?
it allows full recovery while maintaining fitness.
159
Why is the ability to buffer hydrogen ions important for performance?
It helps maintain muscle pH and delay fatigue.
160
How does high-intensity exercise affect mitochondrial function?
It increases mitochondrial density, improving aerobic metabolism.
161
Why do trained individuals have a lower RER at the same intensity as untrained individuals?
They rely more on fat metabolism, sparing glycogen.
162
How does resistance training affect muscle endurance?
It improves fatigue resistance by increasing capillary density and metabolic efficiency.
163
What role does myoglobin play in oxygen consumption?
It transports oxygen within muscle cells to support metabolism.
164
Why is energy expenditure higher during weight-bearing exercise?
It requires greater muscular effort and stabilization.
165
How does chronic high-altitude training affect energy systems?
It enhances red blood cell production and oxygen transport.
166
What is the role of beta-alanine in buffering fatigue?
It increases carnosine levels, helping maintain muscle pH.
167
How does chronic dehydration affect metabolism?
It impairs thermoregulation and nutrient transport.
168
Why do females generally have lower V̇O₂ max than males?
Due to differences in muscle mass and hemoglobin levels.
169
How does caffeine improve endurance performance?
It stimulates the central nervous system and increases fat oxidation.
170
What effect does overtraining have on resting heart rate?
it can increase due to excessive sympathetic activation.
171
Why is post-exercise protein intake important?
It supports muscle repair and glycogen replenishment.
172
How does mental fatigue impact physical performance?
It reduces motivation and neuromuscular drive.
173
How does carbohydrate periodization enhance endurance adaptation?
Training low on glycogen improves fat oxidation efficiency.
174
What role does vasodilation play in heat dissipation?
It increases blood flow to the skin for cooling.
175
How does sleep deprivation impair recovery?
It disrupts hormone regulation and muscle repair.
176
What is the optimal timing for carbohydrate intake post-exercise?
Within 30–60 minutes to maximize glycogen resynthesis.
177
Why does iron deficiency impair endurance performance?
It reduces oxygen transport capacity in the blood.
178
How does neuromuscular coordination affect energy efficiency?
Better coordination reduces unnecessary energy expenditure.
179
What is the impact of chronic stress on metabolism?
It can increase cortisol, leading to muscle breakdown.
180
Why is post-exercise cooling important?
It prevents excessive heat buildup and promotes recovery.
181
How does gut training improve endurance performance?
It increases carbohydrate absorption and reduces gastrointestinal distress.
182
What is the primary determinant of energy cost during running?
Running economy and biomechanics.
183
How does muscle fiber recruitment influence energy expenditure?
More efficient recruitment patterns reduce fatigue.
184
Why is low-intensity exercise better for active recovery?
it promotes circulation without adding excessive stress.
185
How does proper hydration impact endurance capacity?
It maintains blood volume and thermoregulation.
186
How does the crossover concept explain the shift between fat and carbohydrate metabolism?
As exercise intensity increases, carbohydrate use rises while fat oxidation decreases.
187
Why do trained athletes have a lower respiratory exchange ratio (RER) at the same intensity compared to untrained individuals?
They rely more on fat metabolism, sparing glycogen stores.
188
How does exercise intensity influence glycogen depletion?
Higher intensities use glycogen faster, leading to earlier fatigue.
189
Why is lactate not just a waste product but an important fuel source?
It can be converted back to glucose via the Cori cycle or used by other tissues.
190
How does muscle glycogen depletion affect performance in endurance exercise?
It forces greater reliance on fat oxidation, which is slower and less efficient for high-intensity work.
191
How does body temperature affect metabolic rate during exercise?
A higher core temperature increases metabolic rate and energy expenditure.
192
Why is protein generally a minor energy source during exercise?
It is primarily used for tissue repair and enzyme function rather than energy production.
193
What is the primary determinant of energy cost during walking versus running?
Walking speed and gait mechanics; running economy at different paces.
194
How does a high-fat diet influence energy metabolism during endurance exercise?
It may increase fat oxidation but could impair high-intensity performance.
195
Why do trained endurance athletes have higher muscle glycogen storage capacity?
Their muscles adapt to store more glycogen to delay fatigue.
196
What is the primary function of the heart?
To pump blood throughout the body.
197
What is the pacemaker of the heart?
The sinoatrial (SA) node.
198
Q: What type of muscle tissue makes up the myocardium?
A: Highly oxidative cardiac muscle fibers.
199
Q: What does an ECG measure?
A: The electrical activity of the heart.
200
Q: What are the three extrinsic factors that control heart rate?
A: Parasympathetic nervous system, sympathetic nervous system, endocrine system.
201
Q: What is bradycardia?
A: A heart rate lower than 60 beats per minute.
202
Q: What is stroke volume?
A: The volume of blood pumped in one heartbeat.
203
Q: What is cardiac output?
A: The total volume of blood pumped per minute.
204
Q: What is ejection fraction?
A: The percentage of blood ejected from the left ventricle per beat.
205
Q: How does endurance training affect resting heart rate?
A: It decreases resting heart rate, sometimes below 40 bpm.
206
Q: What do arteries do?
A: Carry blood away from the heart.
207
Q: What do veins do?
A: Carry blood back to the heart.
208
Q: What is systolic blood pressure?
A: The pressure in arteries during heart contraction.
209
Q: What is diastolic blood pressure?
A: The pressure in arteries during heart relaxation.
210
Q: What is hypertension?
A: Chronically high blood pressure.
211
Q: What is the function of capillaries?
A: Exchange of oxygen, nutrients, and waste between blood and tissues.
212
Q: What is intrinsic control of blood flow?
A: Local factors that dilate or constrict blood vessels.
213
Q: What is the function of baroreceptors?
A: Detect changes in blood pressure and help regulate it.
214
Q: What helps return blood to the heart?
A: Muscle pump, respiratory pump, venous valves.
215
Q: What is the role of the aorta?
A: Distributes oxygenated blood to the body.
216
Q: What is the average blood volume in adults?
A: 4-6 liters.
217
Q: What are the main components of blood?
A: Plasma, red blood cells, white blood cells, platelets.
218
Q: What protein in RBCs carries oxygen?
Hemoglobin
219
Q: What is anemia?
A: A condition with low red blood cell or hemoglobin levels.
220
Q: What stimulates red blood cell production?
A: The hormone erythropoietin (EPO).
221
Q: How does dehydration affect blood viscosity?
A: It increases blood viscosity.
222
Q: How does exercise affect blood volume?
A: Blood volume increases with training.
223
Q: Why is high blood viscosity dangerous?
A: It makes the heart work harder to pump blood.
224
Q: What is hematocrit?
A: The percentage of blood volume made up of red blood cells.
225
Q: How does altitude affect red blood cell production?
A: It increases RBC production to improve oxygen transport.
226
Q: What is the myocardium?
A: The heart's muscular layer responsible for contraction.
227
Q: Why is the myocardium highly oxidative?
A: To sustain continuous contractions with high endurance.
228
Q: What is the function of the right atrium?
A: To receive deoxygenated blood from the body.
229
Q: What is the function of the left atrium?
A: To receive oxygenated blood from the lungs.
230
Q: What is the function of the right ventricle?
A: To pump deoxygenated blood to the lungs.
231
Q: What is the function of the left ventricle?
A: To pump oxygenated blood to the body.
232
Q: What are the four chambers of the heart?
A: Right atrium, right ventricle, left atrium, left ventricle.
233
Q: What is the sinoatrial (SA) node?
A: The heart’s natural pacemaker.
234
Q: Where is the SA node located?
A: In the right atrium.
235
Q: What is the atrioventricular (AV) node?
A: A secondary pacemaker that delays impulses before passing them to the ventricles.
236
Q: What does the bundle of His do?
A: It transmits electrical signals from the AV node to the ventricles.
237
Q: What are Purkinje fibers?
A: Specialized fibers that conduct electrical impulses to the ventricles.
238
Q: What is an ECG?
A: A recording of the heart’s electrical activity.
239
Q: What is the normal resting heart rate (HR)?
A: 60–85 beats per minute.
240
Q: How low can an elite athlete's resting HR be?
A: Below 40 beats per minute.
241
Q: What is tachycardia?
A: A resting heart rate above 100 bpm.
242
Q: What is bradycardia?
A: A resting heart rate below 60 bpm.
243
Q: What does the parasympathetic nervous system do to heart rate?
A: Decreases heart rate.
244
Q: What does the sympathetic nervous system do to heart rate?
A: Increases heart rate.
245
Q: How does the endocrine system affect heart rate?
A: It releases hormones like epinephrine to increase HR.
246
Q: What is the cardiac cycle?
A: All mechanical and electrical events in one heartbeat.
247
Q: What is stroke volume?
A: The amount of blood pumped per beat.
248
Q: What is cardiac output?
A: The total blood pumped per minute.
249
Q: What is ejection fraction?
A: The percentage of blood ejected from the left ventricle per beat.
250
Q: What is ventricular fibrillation?
A: A life-threatening, uncoordinated contraction of the ventricles.
251
Q: What is atrial fibrillation?
A: Rapid, irregular atrial contractions.
252
Q: What is ventricular tachycardia?
A: A rapid heartbeat originating in the ventricles.
253
Q: What does PVC stand for in cardiac arrhythmias?
A: Premature Ventricular Contractions.
254
Q: What is systole?
A: The contraction phase of the heart.
255
Q: What is diastole?
A: The relaxation phase of the heart.
256
Q: What is preload?
A: The volume of blood returning to the heart.
257
Q: What is afterload?
A: The resistance the heart must overcome to pump blood.
258
Q: How does exercise affect stroke volume?
A: Increases stroke volume.
259
Q: What is the Frank-Starling mechanism?
A: The greater the heart fills, the stronger the contraction.
260
Q: What is blood pressure?
A: The force of blood against arterial walls.
261
Q: What is systolic blood pressure?
A: Pressure during heart contraction.
262
Q: What is diastolic blood pressure?
A: Pressure during heart relaxation.
263
Q: What is mean arterial pressure?
A: The average blood pressure in arteries.
264
Q: What is vasoconstriction?
A: Narrowing of blood vessels.
265
Q: What is vasodilation?
A: Widening of blood vessels.
266
Q: What regulates blood vessel diameter?
A: The autonomic nervous system.
267
Q: What is blood volume?
A: The total amount of blood in the body.
268
Q: What is the normal blood volume in adults?
A: 4-6 liters.
269
Q: What is the function of platelets?
A: Blood clotting.
270
Q: How does exercise affect blood volume?
A: Blood volume increases with training.
271
Q: What happens to blood flow during exercise?
A: More blood is directed to working muscles.
272
Q: What is the function of white blood cells?
A: Immune response.
273
Q: What is the role of plasma?
A: Transports nutrients, hormones, and waste.
274
Q: What is hypoxia?
Answer
275
Q: What effect does altitude have on RBC production?
A: Increases RBC production to improve oxygen transport.
276
Q: What is cardiovascular drift?
A: A gradual increase in heart rate during prolonged exercise due to dehydration and rising body temperature.
277
Q: How does endurance training affect resting heart rate?
A: Lowers resting heart rate due to increased vagal tone.
278
Q: What is the primary fuel for the heart at rest?
A: Fatty acids.
279
Q: What is the primary fuel for the heart during intense exercise?
A: Carbohydrates.
280
Q: What is the Fick equation?
A: VO₂ = Cardiac Output × (a-v)O₂ difference.
281
Q: What does (a-v)O₂ difference measure?
A: The difference in oxygen content between arterial and venous blood.
282
Q: What is VO₂ max?
A: The maximum oxygen consumption during intense exercise.
283
Q: What is the main determinant of VO₂ max?
A: Cardiac output.
284
Q: How does endurance training affect stroke volume?
A: Increases stroke volume.
285
Q: How does stroke volume respond to exercise intensity?
A: Increases up to about 50-60% of VO₂ max, then plateaus.
286
Q: What is oxygen debt?
A: The amount of oxygen required to restore the body to its resting state after exercise.
287
Q: How does training affect blood volume?
A: Increases blood volume due to plasma expansion.
288
Q: How does training affect capillary density in muscles?
A: Increases capillary density, improving oxygen delivery.
289
Q: How does training affect heart size?
A: Increases left ventricular volume and wall thickness.
290
Q: What is cardiac hypertrophy?
A: Enlargement of the heart muscle due to chronic training.
291
Q: How does resistance training affect the heart?
A: Increases left ventricular wall thickness without major chamber enlargement.
292
Q: What is the lactate threshold?
A: The point at which blood lactate accumulates during exercise.
293
Q: How does endurance training affect lactate threshold?
A: Increases the lactate threshold, allowing higher intensity before fatigue.
294
Q: What is the role of nitric oxide in the vascular system?
A: It causes vasodilation, improving blood flow.
295
Q: What happens to heart rate recovery time with training?
A: It shortens, indicating better cardiovascular fitness.
296
Q: How does chronic exercise affect resting blood pressure?
A: Lowers both systolic and diastolic blood pressure.
297
Q: How does heart rate respond to submaximal exercise after endurance training?
A: Decreases for a given workload.
298
Q: What cardiovascular adaptation helps endurance athletes sustain high-intensity exercise?
A: Increased mitochondrial density and capillary supply to muscles.
299
Q: How does maximal cardiac output change with training?
A: Increases due to a larger stroke volume.
300
Q: What is hypertension?
A: Chronically high blood pressure (≥130/80 mmHg).
301
Q: What is the leading cause of death in the U.S.?
A: Cardiovascular disease.
302
Q: What is atherosclerosis?
A: The buildup of plaque in the arteries, narrowing blood flow.
303
Q: What are the primary risk factors for cardiovascular disease?
A: Smoking, high blood pressure, high cholesterol, physical inactivity, obesity, diabetes.
304
Q: What is an ischemic stroke?
A: A stroke caused by a blocked artery, reducing blood flow to the brain.
305
Q: What is a hemorrhagic stroke?
A: A stroke caused by a ruptured blood vessel in the brain.
306
Q: What is myocardial infarction?
A: A heart attack, caused by blockage of coronary arteries.
307
Q: What is angina pectoris?
A: Chest pain due to reduced blood flow to the heart.
308
Q: What are HDL and LDL?
A: High-density lipoprotein (good cholesterol) and low-density lipoprotein (bad cholesterol).
309
Q: What is the role of cholesterol in heart disease?
A: High LDL contributes to plaque buildup in arteries.
310
Q: What is heart failure?
A: The heart’s inability to pump enough blood to meet body demands.
311
Q: What is arrhythmia?
A: An irregular heartbeat.
312
Q: How does exercise help prevent cardiovascular disease?
A: Lowers blood pressure, increases HDL, improves circulation.
313
Q: What is the effect of chronic stress on heart health?
A: Increases risk of hypertension and heart disease.
314
Q: How does diabetes increase cardiovascular disease risk?
A: High blood sugar damages blood vessels and increases inflammation.
315
Q: What is metabolic syndrome?
A: A cluster of conditions increasing heart disease risk, including obesity, high BP, high blood sugar.
316
Q: What are beta-blockers?
A: Medications that lower heart rate and blood pressure.
317
Q: What is the role of aspirin in heart disease prevention?
A: It reduces blood clot formation.
318
Q: What is a pacemaker?
A: A device that regulates heart rhythm.
319
Q: What is angioplasty?
A: A procedure to open narrowed arteries using a balloon and stent.
320
Q: What is coronary bypass surgery?
A: Surgery that reroutes blood around blocked arteries.
321
Q: What is the impact of smoking on the cardiovascular system?
A: Increases plaque buildup, reduces oxygen transport, raises blood pressure.
322
Q: What is the American Heart Association's recommended physical activity level?
A: At least 150 minutes of moderate or 75 minutes of vigorous exercise per week.
323
Q: What are the warning signs of a heart attack?
A: Chest pain, shortness of breath, nausea, cold sweat, dizziness.
324
Q: How does obesity affect heart health?
A: Increases blood pressure, cholesterol, and inflammation.
325
Q: What is sudden cardiac arrest?
A: A sudden loss of heart function due to electrical disturbances.
326
Two systems coordinating physical activity?
Nervous and endocrine (neuroendocrine system
327
Front: Function of endocrine glands?
Back: Secrete hormones to regulate cells/organs
328
Front: What do target cells contain?
Back: Specific hormone receptors
329
Front: Steroid hormones are derived from?
Back: Cholesterol
330
Front: Are steroid hormones lipid-soluble?
Back: Yes
331
Front: Nonsteroid hormones are made of?
Back: Peptides and amino acids
332
Front: Are nonsteroid hormones lipid-soluble?
Back: No
333
Front: What regulates hormone secretion?
Back: Negative feedback
334
Front: Effect of downregulation?
Back: Decreases receptor number
335
Front: Effect of upregulation?
Back: Increases receptor number
336
Front: How do steroid hormones act?
Back: Bind receptors in membrane, cytoplasm, nucleus
337
Front: What do steroid hormones activate?
Back: Gene transcription (mRNA synthesis)
338
Front: How do nonsteroid hormones work?
Back: Via secondary messengers (e.g., cAMP)
339
Front: What effect does exercise have on hormones?
Back: Increases hormone release
340
Front: Anterior pituitary hormones?
Back: Growth hormone, prolactin
341
Front: Thyroid gland hormones?
Back: Thyroxin, triiodothyronine
342
Front: Adrenal medulla hormones?
Back: Epinephrine, norepinephrine
343
Front: Adrenal cortex hormones?
Back: Aldosterone, cortisol, sex hormones
344
Front: Pancreatic hormone increasing glucose?
Back: Glucagon
345
Front: Pancreatic hormone decreasing glucose?
Back: Insulin
346
Front: Hormones increasing plasma glucose?
Back: Glucagon, epinephrine, norepinephrine, cortisol
347
Front: What increases muscle glucose uptake?
Back: Insulin and exercise
348
Front: What controls lipolysis rate?
Back: Insulin, epinephrine, norepinephrine, cortisol, growth hormone
349
Front: Why is fluid balance important?
Back: Supports metabolic, cardiovascular, thermoregulation
350
Front: Posterior pituitary hormone for fluid balance?
Back: ADH (vasopressin)
351
Front: What triggers ADH release?
Back: Increased plasma osmolality
352
Front: Adrenal cortex hormone for fluid balance?
Back: Aldosterone
353
Front: What triggers aldosterone release?
Back: Low blood volume and pressure
354
Front: What organ also regulates fluids?
Back: Kidneys
355
Front: Primary appetite center?
Back: Hypothalamus
356
Front: What nucleus controls satiety?
Back: Ventromedial nucleus
357
Front: What nucleus controls hunger?
Back: Lateral hypothalamus
358
Front: Function of CCK?
Back: Satiety signal
359
Front: Function of GLP-1?
Back: Satiety signal
360
Front: Function of PYY?
Back: Satiety signal
361
Front: Function of ghrelin?
Back: Increases hunger
362
Front: What hormone decreases appetite?
Leptin
363
Front: What happens to leptin in obesity?
Back: Increases
364
Front: Effect of vigorous exercise on PYY, GLP-1?
Back: Increases
365
Front: Effect of vigorous exercise on ghrelin?
Decreases
366
Front: Does exercise training alone affect ghrelin?
No
367
Front: What increases ghrelin after weight loss?
Back: Exercise training
368
Front: Example of steroid hormone?
Cortisol
369
Front: Example of nonsteroid hormone?
Insulin
370
Front: Function of epinephrine?
Back: Increases heart rate, metabolism
371
Front: Function of norepinephrine?
Back: Vasoconstriction, alertness
372
Front: Function of cortisol?
Back: Increases glucose, suppresses inflammation
373
Front: Function of aldosterone?
Back: Retains sodium, increases BP
374
Front: What is negative feedback?
Back: Hormone secretion inhibition when levels are high
375
Front: What does growth hormone do?
Back: Promotes muscle/bone growth
376
Front: What organ secretes insulin?
Pancreas
377
Front: What does oxytocin do?
Back: Stimulates childbirth contractions
378
Front: What organ releases ADH?
Back: Posterior pituitary
379
Front: What increases plasma glucose?
Back: Glucagon, epinephrine, cortisol
380
Front: How does insulin lower glucose?
Back: Increases muscle glucose uptake
381
Front: Role of thyroid hormones?
Back: Increase metabolism
382
Front: What happens to insulin during exercise?
Decreases
383
Front: What stimulates glucagon release?
Back: Low blood glucose
384
Front: What triggers cortisol release?
Back: Stress, low glucose
385
Front: Role of hypothalamus?
Back: Regulates appetite, metabolism
386
Front: What do mineralocorticoids regulate?
Electrolytes
387
Front: What happens if ADH is low?
Back: Increased urine output
388
Front: How does exercise impact fluid balance?
Back: Increases water loss
389
Front: What suppresses ghrelin?
Exercise
390
Front: What does leptin do long-term?
Back: Regulates body fat
391
Front: Function of prolactin?
Back: Milk production
392
Front: What stimulates PYY release?
Back: Food intake
393
Front: What does GLP-1 do?
Back: Enhances insulin secretion
394
Front: What is cAMP?
Back: Secondary messenger for nonsteroid hormones
395
Front: Role of secondary messengers?
Back: Amplify hormone effects
396
Front: What does exercise do to cortisol?
Back: Increases during prolonged activity
397
Front: What gland releases thyroid hormones?
Thyroid
398
Front: What stimulates the adrenal medulla?
Back: Sympathetic nervous system
399
Front: What hormone retains sodium?
Aldosterone
400
