Lecture 23 Flashcards
What is the purpose or ergogenic aids?
To improve performance
Performance can be improved in what three ways?
- increasing the physiological capacity of a particular body system
- increasing the speed of recovery
- decreasing the perception of fatigue or increasing motivation and aggression
The ergogenic aids can come in what three forms?
- mechanical
- chemical/pharmacological
- physiological
What are three examples of mechanical ergogenic aids?
- altitude training
- nasal strips
- compression garments
How does altitude training work as a mechanical ergogenic aid?
There is less O2 in the air when you train which means that you increase the capacity to trap O2 in the blood stream.
The RBC count increases as the kidneys have released EPO to increase RBC and Hb
How do nasal strips work as a mechanical ergogenic aid?
These are used by endurance athletes. You stick them across your nose to help open up the nasal passages to increase O2 uptake. There is no evidence that this actually works
How do compression garments work as a mechanical ergogenic aid?
This is to increase venous return
What are 5 examples of pharmacological/chemical aids? Which of these are legal and which are illegal?
anabolic androgenic steroids which are not permitted
caffeine, nitrates, creatine (and other supplements) are permitted
Explain how anabolic androgenic steroids work
These are based on androgens. They affect the activity of the muscle and bones. Their purpose is to increase muscle hypertrophy, increase EPO, increase aggressiveness, increase bone growth. There are also many side effects such as liver failure
Studies show that performance is enhanced by caffeine intake at what dose?
2-6mg/kg
How does caffeine affect performance?
It increases fat metabolism over glycogen metabolism in endurance athletes ie. it pushes muscles to metabolise fat
Do all studies show caffeine to be beneficial? Explain this
No
Not all studies show enhanced performance and if a regular coffee drinker then caffeine is limited in its effects
Are there any side effects to using caffeine as a performance enhancer?
No apparent adverse side effects, diuretic at really large doses beyond that used for performance
Where is one place we get nitrate supplementation from?
beetroot juice
How does nitrate/beetroot juice enhance performance?
It increases nitrate concentration which increases the ability of endothelial cells and smooth muscle cells to be producing NO for improved vasodilation to increase blood flow to muscles. There is also sympatholysis and increased efficiency of oxidative phosphorylation. It helps remove the metabolic waste build up during exercise
How much Nitrate/Beetroot juice do you need for it to be beneficial?
> 500mg nitrate 75 mins pre-exercise to improve running speed
Who do the benefits of Nitrate/Beetroot juice affect most?
low to moderately trained athletes
What is the purpose/benefit of creatine as a supplement?
A few days of high creatine intake (free creatine plus creatine phosphate) increases the skeletal muscle content by 20-30%. This increases performance in brief high-intensity exercise
Are sports supplements safe to use?
They are assumed safe to use but there is no pre-market review for their safety or efficacy (ie. there is no review to see if it is safe)
What are two examples of physiological aids?
- acupuncture
- blood doping (including cobalt supplementation)
What is the purpose of acupuncture?
To alleviate muscle tensions
Explain how blood doping works
The athlete takes blood out and freezes it during the off season and puts it back in later during the racing season. EPO could also be injected which also increases the red blood cell number to allow the muscles to work longer and harder without cramping
How can you detect blood doping?
There is no direct detection method, you just have to monitor the haematological values (haematocrit)
What is the purpose of blood doping?
To increase the RBC count which means that you can get more O2 to skeletal muscle (so there is increased carrying capacity) and increased VO2 max
Explain what cobalt supplementation does
Instead of injecting blood to improve haematocrit, you can inject cobalt. This stabilises hypoxia inducible factor which mimics hypoxia. This means that you need to make more RBC to grab more O2 so the O2 carrying capacity is increased
What is the potential issue of cobalt supplementation?
It could have carcinogenic effect
What is the purpose of recombinant EPO?
It increases the RBC count and increases the O2 capacity of the blood
Why is it hard to detect blood doping?
Because there is only a small window of opportunity (2-3 days) and the levels are only high 12 - 18 hours after injection. Therefore small amounts more often is more common
How does EPO work?
It is released from the kidneys and it enters the circulation, then goes into the bone marrow to produce more RBC
What is the problem with having a haematocrit that is too high?
There are too many blood cells which can form clots
What could a measurement outside the normal limits on the biological passport indicate?
doping or an underlying health condition
What are reticulocytes? What does this have to do with the RBC count? How does this relate to doping?
When RBC are made, you first make them as a reticulocyte (if there is not enough RBC, the number of reticulocytes increases). Therefore we would expect the number of RBC to increase right after the increase in reticulocytes. Normally, as you do exercise, you lose RBC because they get damaged because they are being squeezed through small capillaries in skeletal muscle. Lance Armstrong’s reticulocyte level stayed low but his RBC shot up before the TDF which is indicative of doping
