Physiology Of Exercise Flashcards
Term used to describe a muscle cell
Muscle fiber
A single nerve and group of muscle fibers it innervates is
Motor unit
What does each muscle cell contain
Organelles
Mitochondria
Myofibrils
What are sarcomeres?
Functional unit of the myofibril
Responsible for contractile properties of the muscle
Describe type i fibers
Slow twitch
High level of aerobic endurance
What activities are type i fibers used in?
ADLs
Walking
Low intensity endurance events - biking or jogging
Describe type II fibers
Fast twitch
Poor endurance capacity
Work better anaerobically
What activities entail type IIa fibers?
Higher intensity events of short duration
Half mile run
Strength training workout
What activities entail type IIx fibers?
Explosive activities
50 meter dash
Weightlifting
Functions of the cardiorespiratory system
Deliver oxygen and nutrients to working muscles
Remove metabolic waste products and CO2
Transporting hormones
Assisting in thermoregulation
Fluid balance
Maintaining acid-base balance
Normal range for heart rate
60-100 bpm
What is stroke volume?
Volume of blood pumped during one heartbeat
What is cardiac output?
Total volume of blood pumped from one heartbeat
Heart rate X stroke volume
What is VO2 max?
Maximal oxygen uptake
Which is more important, lung gas exchange or glycogen availability?
Glycogen availability
Percentage of protein used in body’s energy needs
5-10%
Maximal amount of carbs (as kcal) that can be stored in the body
1600-2500 kcal
What is the fastest way to generate ATP?
ATP CP cycle
Due to limited supplies it only lasts up to 10 seconds
What is the biologically usable form of energy?
Adenosine Triphosphate (ATP)
What are the 3 basic metabolic pathways to rephosphorylize ADP?
Aerobic
Anaerobic
Phosphocreatine pathway
What amino acids can synthesize creatine?
Methionine
Arginine
Glycine
How does the ATP PC pathway work?
A creatine kinase enzyme separates the phosphate from phosphocreatine and attaches itself to ADP forming ATP
What two energy systems are used in the first few minutes of exercise?
ATP-PC system
Anaerobic glycolysis
Another name for aerobic glycolysis
Oxidative phosphorylation
What two pathways does aerobic glycolysis use?
Krebs Cycle
Electron Transport Chain
How many ATP can be generated via carbs or fat?
Carbs - 32
Fat - 106
Drawbacks to using fat as a fuel source regarding ATP
Slow process
Can only be generated aerobically (with oxygen)
Possible causes of short term fatigue
Accumulation of metabolic products such as inorganic phosphate and lactate
Depletion of creatine phosphate
Changes in cellular calcium
What 2 reputable places can you find credentialed exercise professionals?
ACSM ProFinder
USREPS (US Registry of Exercise Professionals)
What is a MET?
Metabolic Equivalent
Ratio of the rate of energy expended during exercise compared to the rate of energy expended during rest
What are the ranges for light, moderate, and vigorous intensity METs
Light - 1.1 - 2.9
Moderate - 3.0 - 5.9
Walking 3.3 mph
Vigorous - greater than or equal to 6
Running a 10 minute mile
What is short term or metabolic fatigue due to?
Reliance on anaerobic metabolism
Build up of lactate
What is long term or substrate fatigue due to?
Glycogen depletion
“Hitting the wall” or “bonking”
What is the equation for VO2 max
mL X kg-1 X min-1
How to calculate maximum heart
208 - 0.7(age)
