Muscles
Is there an increase in muscle fibers when you train a muscle to hypertrophy?
No ( in general), the fibers grow in size but do not multiply (except very rarely)
Where is glycogen stored in the body?
Liver and muscles (mostly)
What is the VO2 max?
The rate of oxygen usage during maximal aerobic metabolism - L/min
Which organ system is the limiting factor for the VO2 max?
What 2 things makeup the cardiac output?
Stroke volume and heart rate
What is heatstroke?
In which gender has most sports research been done and why?
Men and sexism
Name 2 of the 3 metabolic systems of the muscles?
Phosphogen System
Glycogen and Lactic Acid System
Aerobic System
Bonus: What are the 2 molecules that are used in the phosphogen system?
Do we breath maximally when performing hard exercise?
No - the maximum breathing capacity is about 50% higher than pulmonary ventilation during hard exercise
Bonus -
Why?
What happens to blood flow during heavy exercise?
Blood flow to the muscles increases and blood flow to the internal organs generally decreases.
What is the treatment for heatstroke?
Cool em down
1. ice bath
2. cool mist plus continuous airflow on uncovered skin
What is the holding strength of muscle?
The additional strength needed to forcefully stretch a muscle that is maximally contracted, about 40% more than the max contractile strength.
What is the oxygen diffusing capacity of capillaries and how does it differ in endurance athletes compared to normies?
that rate that oxygen diffuses into the blood from the alveoli.
It is higher in athletes
Bonus:
Why?
Endurance athletes have an average maximum cardiac output that is 6x higher than a normal person. Why is this? At rest they have the same cardiac output. Why is this?
Stroke volume is increased due to cardiac hypertrophy and enlargement of the heart chambers.
The resting heart rate is lower in endurance athletes.
This is a gimme. How does old age affect exercise capacity with respect to 2 organ systems?
Muscles atrophy due to sedentary lifestyle
Cardiac output decreases 50 % from 18-80
Maximum ventilation decreases by more than 50% in the same period.
Name 3 of the 5 changes that occur when hypertrophying a muscle
1. Increased myofibrils
2. Increased mitochondrial enzymes
3. Increased glycogen storage
4. increased phosphogen system components
5. Increased triglyceride storage
You are a sprinter that specializes in the 400 m dash. Which metabolic system(s) are going to be used during your race?
Phosphogen and lactic acid system.
Phosphogen is active for 10 s
Glycogen-lactic acid is active for 1.3-1.6 min
Aerobic is unlimited (if nutrients available)
Which factor contributes the most to the increase in cardiac output during heavy exercise (in the same person)?
The increase in heart rate. Stroke volume increase on average by 50% but heart rate increases by 270 -300%
What are some of the negative effects that are associated with the use of anabolic steroids? Name and explain 2
Heart attacks and strokes - decrease HDL and LDL and increase hypertension
Decreased sperm count due to decreased secretion of FSH and LH
Decreased natural testosterone
Women develop male sexual characteristics
What is the difference in strength per square centimeter between the muscles of females and the muscles of males?
There is no difference. It is 3-4 kg/cm^3
How many days does it take to fully restore glycogen after heavy exercise in someone following a high carb diet versus a high fat diet?
High carb - 2 days
High fat - does not recover (after 5 days in studies)
How do the blood gas concentrations (O2 and CO2) change when comparing someone exercising maximally and someone at rest?
They are essentially unchanged.
Bonus: Then how does the body know to increase respiration?
An athlete is about to do a marathon in Arizona (very hot). They have been training in Arizona for 2 weeks. They want to know if they should use sodium chloride tablets during their run. What do you think?
No. After 2 weeks, sweat glands are acclimatized to the heat and reabsorb sodium and chloride. It is therefore unnecessary and potentially harmful to increase their salt intake.