Exercise Physio Flashcards
What are the three systems of ATP generation?
Phosophocreatine System
Glycolytic System
Aerobic System
What is Phosphocreatine?
High-energy cmpd in muscle used to generate ATP by donating a phosphate to ADP
How much ATP is made from 1 mol of PCr?
1 mol ATP
What is the fastest mechanism for ATP regen during muscle activity?
Direct Phosphorylation
What kind of activities would use the PCr System?
Activities that require only a few seconds (8-10 seconds)
What is the Glycolytic System?
ATP production in the cytoplasm via breakdown of glycogen in the absence of oxygen
What is produced during the Glycolytic System?
Lactic Acid
How much ATP is produced from 1 mol Glucose?
2 mol ATP
What kind of activities would use the glycolytic system?
Moderate-duration exercise (1-3 minutes to an hour)
WHat is the Aerobic System?
ATP Synthesis in the Mitochondria involving the oxidation of CHO, Fatty Acids, or Amino Acids derived from food, which entire the cycle as Acetyl CoA and yield ATP through the Electron Transport Chain
How much ATP is formed with 1 mol of glucose?
36 (30-32) ATP
What is the slowest mechanism for regenerating ATP during muscle activity?
Aerobic Respiration
What are two types of endogenous fuel sources?
Fats and Glycogen
What are two types of exogenous fuel sources?
Free fatty acids, glucose
from food
What are the three parameters of exercise?
Speed, Endurance, Strength
TF: Strength is proportional to the cross-sectional area of the muscle
True
Which generates more strength? Pennate Muscles or Fusiform Muscles. Why?
Pennate Muscles because they have more insertions -> More Force
What is recruitment?
Proper sequencing of discharge of motor units
What two factors influence recruitment?
Degree of motor unit firing
Frequency of firing
What is the Size Principle?
Slow smaller muscle fibrs before bigger and fast muscles contract
What is the synchronization ratio?
Degree to which motor units fire simultaneously to produce maximum tension
Which type of sports use Type 1 Muscles?
Light exercise, endurance
Which type of sports use Type 2 Muscles?
Moderate to severe (sports that require speed)
What is the Equilibrium Length of a muscle?
Length of muscle when extracted from the body
What is the Resting Length of a muscle?
Length of the muscle when body is at rest; Point of maximum tension from active and passive tension forces in the muscle
Which is longer? Resting or Equilibrium Length?
Resting Length is slightly more stretched
Which generates greater force? Muscle at Equilibrium Length or Resting Length?
Resting Length
What kind of exercises should one do to train for strength?
Lengthening Contraction Exercises (more force)
Isometric Exercise
What kind of exercises should be done to train for flexibility?
Shortening contractions
To exhibit the greatest force, one must show what type of contraction?
Rapid eccentric contraction
To exhibit the least force, what type of contraction?
Rapid concentric contraction
TF: If a muscle insertion is further, less force is exerted?
False
What kind of activities use Type 1 muscles?
Slow sustained activities; jogging, cycling, endurance
What kind of activities use Type 2 muscles?
Rapid powerful movements
What is strength?
Maximum force a muscle can do
What is endurance?
Ability to sustain an effort over time
If there is fast shortening of a muscle, what happens to the force?
Drops
If there is fast lengthening of a muscle, what happens to the force?
Increases
TF: If one exhibits less than 15% of max, one can theoretically go on for forever.
True
Which fibers are important in endurance activities?
Type 1 Fibers
What are the two types of endurance?
Muscular Endurance
General/Total Endurance
What is muscular endurance?
Ability of a muscle to contract repeatedly or to generate and sustain tension
What type of fibers do speed activities require?
Type II Fibers
What is specificity?
Practicing a desired movement
What is overload?
Stress beyond usual requirements for greater efficiency
TF: Specificity exceeds overload.
False
What type of intensity should one do while training for endurance events?
High reps, but low intensity
What type of intensity should one do while training for strength?
Low reps, but high intensity
Which type of muscle fiber fatigues earlier?
Type 2
TF: When fatigued, there is an increase in acetylcholine in the NMJ.
False; decrease
What is the essential role of the cardiovascular system in exercise?
Deliver oxygen/nutrients to muscles
Remove CO2 and metabolic products
Dissipate heat
What is the percentage of the blood flow of the heart during exercise?
Forever 4% even while the absolute amount changes
The brain always maintains how much mL/min?
750 mL/min even while the proportion changes
Blood flow to active muscles ____, while blood flow to inactive muscles ______.
Increase; decrease
Cardiac output increases _____ with O2 consumption.
Linearly
Distribution of bloodflow of the heart
Remains the same 4% (but absolute amount increases)
Distribution of blood flow to the brain
Remains the same at 750 mL (but proportion decreases)
Distribution of blood flow to active muscles
Increases
Distribution of blood flow to inactive muscles
Decreases
Distribution of blood flow to skin
Increases
Distribution of blood flow to splanchnic muscles
Decreases
Distribution of blood flow to others
Decreases
Cardiac bloodflow
Increases
TF: If one does not cool down , you may get syncope due to blood volume in the brain decreasing.
True
What is the cardiac output?
Amount of blood put out by heart.
Cardiac Output increases ____ with O2 consumption.
Linearly
Cardiac output increases in _____ to intensity of exercise.
Proportion
Cardiac Output can also be measured by the…
Max VO2
What is the Max VO2?
Measure of the aerobic capacity of an individual to work
What is the Stroke Volume?
Amount of blood that is pumped out as the ventricles empty during systole.
Trained individuals exhibit ____ heart rate, but ___ stroke volume.
Slower, increased
What are the two mechanisms that regulate stroke volume?
Intrinsic Frank-Starling Mechanism
Neurohormonal: Sympathetic Catecholamines
What is the Intrinsic Frank-Starling Mechanism?
Refers to the intrinsic ability of the heart to adapt to increasing volumes of inflowing blood
How does the neurohormonal mechanism work?
Sympathetic Catecholamines increase cardiac contractility -> greater systolic emptying -> greater stroke volume
TF: Systolic pressure increases more than diastolic pressure.
True
Characteristics of an athlete’s heart
Hypertrophy
Runners and Swimmers: LV volume increased, Ventricular wall thickness normal
Resistance Athletes (strength): LV volue normal; Ventricular wall thickness increased
Ventilation is controlled in two ways by physical activity:
Skeletal muscles and joints Chemical Stimuli (pO2 and pCO2)
What is the effect of a rise in temperature on ventilation?
Lower acidity of fluids
Enhance H+ activity -> Increase CSF acidity
Sensitize Peripheral Chemoreceptors in Arteries
What is hyperventilation?
Ventilation > Metabolic Needs
Hyperventilation can cause…
Restricted venous return, decreased blood supply in brain, fainting or dizziness
What happens to the exchange of gases during exercise?
Alveolar L2 pressure increases and alveolar CO2 pressure decreases
Venous PO2 decreases and Venous PCO2 increases
How does exercise influence the diffusing capacity in the lungs?
Physical training -> Larger lung volumes -> Increased SA between alveoli and capillaries -> Improved diffusion
How do temperature and acidity effect hemoglobin saturation?
Temp rise and pH drop -> lowered O2 affinity of Hemoglobin -> more O2 available to exercising muscles
During Submaximal exercise, what happens to plasma glucose and insulin?
Declines
Submax Exercise: What happens after a drop occurs in plasma glucose?
Accelerated increase of glucagon
Submax Exercise: An increase in glucagon will cause
hepatic glycogen breakdown (glycogenolysis) to occur -> increased plasma glucose
Submax Exercise: What causes insulin to decline
Alpha adrenergic inhibition of pancreatic beta cells
Submax Exercise: A decline in insulin leads to
Decreased Hepatic Glycogen synthesis
Diminish glucose uptake in non-exercising tissues
Release the inhibition on FFA metabolism allowing Lipolysis to proceed
Submax Exercise: What happens to catecholamines at early stages of exercise?
Increases
Submax Exercise: Catecholamine increase will cause
- Enhanced liver and muscle glycogenolysis -> increased CHO
- Inhibit pancreatic secretion of insulin
- Stimulate adipose tissue Lipolysis -> increase plasma FFA
Submax Exercise: What happens to growth hormone and cortisol levels?
Increases
Submax Exercise: What does cortisol do?
Activates epinephrine effect on hepatic glycogenolysis
Submax Exercise: GH and cortisol will…
Impair insulin action
Moderate intensity: HGO and peripheral glucose usage is…
Equal
Moderate intensity: TF - Steady state condition is dependent of the changes in insulin and glucagon concentration
False; independent
High-Intensity: HGO ___ peripheral glucose usage
exceeds –> Hyperglycemia
A precompetition meal should be
High in CHO (immediate energy source)
Low fats/proteins (digest slowly)
