Chapter 2 Flashcards
What are free radicals?
Highly unstable, chemically reactive, contains at least one unpaired electron.
What happens 95% of the time with the ETC?
O2 will be consumed, ATP will be formed, CO2 gas formed and water and other elements are going to leave the mitochondria.
What happens 2-3% of the time with the ETC?
Super oxide!
What are the bad things that can happen because of super oxide?
O- binds to lipid layer and starts to disintegrate it… causing passages to be destroyed and overall functioning to be bad. As well as DNA destruction and mutations to the DNA.
What is the term for destroying the membrane?
Lipid peroxidation
Lipid peroxidation can cause…?
DNA destruction, DNA mutation, cardiac dysfunction and neurodegenerative dysfunction, as well as in some cases cancer.
Explain what oxidative stress is.
As you exercise, you increase your oxygen consumption and that increases the appearance of more super oxides which allow you susceptible to a lot of damage.
What combats our super oxides?
Our antioxidants and our vitamin E, C and A
What is the equation for antioxidants combating super oxide?
O- + O- ——–(superoxide dismutase)——-> H2O2 + O2
What happens when antioxidant enzyme comes into contact with free radicals?
It turns it into hydrogen peroxide (still a free radical, but not as radical as O-) and oxygen. Still want to break down H2O2 so….
H2O2 ———(catalase)———> H2O + O2
catalase is another antioxidant enzyme.
This way the free radicals are neutralized!
Which vitamin is the strongest: E, C or A?
E
Why do they combat super oxides?
Because they contain antioxidants themselves!
Explain what antibiotic defense up regulation means.
The antibiotic defense upregulates, so with more exercise experience (more training), the better this process to fight back will be! The more fit you are, the better.
What is calcium important for?
muscle contraction, propagation of AP, bone formation, development of bone-mineral density (BMD)
Aging results in __________ BMD.
Decreased
When do we start to see a decrease in BMD (age)?
30 years old
Is BMD genetic?
Yes, when looking at BMD levels when older.
What is osteopenia?
Weakened bone structures
Which SD is osteopenia?
1 SD below normal deviation.
What is osteoporosis?
Weakened bone density
What is the SD for osteoporosis?
Equal to or greater than 2.5 SD below normal deviation
What range of kids have osteoporosis?
10-13 years old
What is the primary defense against bone loss with age?
Calcium uptake
What are the best type of exercise for improving bone loss?
Strength and power
When are the benefits of exercise on bone density greatest?
During childhood and adolescence (hence when peak bone mass increases to the greatest extent).
Explain the female triad.
1) Increase in activity (6-8 hours a day)
2) Food intake low/poor diet
3) Decrease in estrogen (promotes bone density; this decrease is brought on by intensity and level of training)
Also, no menstrual cycle… until almost 18.
How can you measure BMD?
DEXA - dual energy xray absorptiometre.
What does osteoporosis LOOK like?
Hole-y bones
Is DEXA high or low dosage of xray?
low
