EPO

Question 1

What is EPO?

Answer 1

• Erythropoietin - produced in the kidneys to stimulate RBC production
• EPO injection elevate Hb and Hct
• Hypoxic conditions creates EPO - produced during big bleed as loss of RBC creates hypoxic conditions
• We can artificially administer EPO
• Traditionally, athletes will take blood and freeze it, liver detects drop in RBC and therefore creates more EPO. Infuse the blood back into the body and there is extra EPO

Question 2

EPO in the muscle tissue:

Vitro
Rodent
Human

Answer 2

Vitro
- EPO improves JAK2, AKT, STATS (signalling proteins)

Rodent
- Unsure about JAK2, improves AKT, doesn’t improve STATS

Human
- JAK2 not studied, doesn’t improve AKT or STATS

Question 3

Birkland et al (2000)

Answer 3

• Injected EPO for 30 days, 3x per week vs control

Haematocrit:

• Rise in Hct to 50% (International Cycling Union Upper Limit)
• 2 subjects stopped as Hct level got too high
• RBC has short half lift, returned to baseline when injections stopped

Haemoglobin
- Increased to about 10%

• Increased Vo2max and TTE with EPO - falls back to baselines after administration

Question 4

Thomson et al (2007)

Answer 4

• Injections aimed to peak Hct levels at 50%
• Less injections over longer duration (harder to detect)
• Increased level of arterial levels of oxygen
• Sig increase in Watt max vs CON at 4 and 11 weeks
• Vo2max sig increased at 4 and 11 weeks
• Increased TTE at same absolute but not relative intensity in week 11 compared to week 1

Question 5

Durussell et al (2013)

Answer 5

Runners vs non-runners - EPO administered for 4 weeks

Vo2max:
- Increased in runners and non-runners after 4 weeks

• Increased in non-runners but not runners after 8 weeks

TT - 3k:

• 6% improvement after 4 weeks
• 3% improvement after 8 weeks

Question 6

Ekholm et al (1991)

Answer 6

• Increased max aerobic power when taking EPO

- Max aerobic power returned to baseline after 4-weeks of administration

Question 7

Nordsborg et al (2014)

Answer 7

• Injection given every other day for 2 weeks, followed by 1 week for the remainder of the trial
• Measured pre/post 15min steady state before ramp test to exhaustion
• Post group had 2 hour break before haemodilation
• No difference in potassium and hydrogen ion accumulation pre/post

Question 8

Guadalupe-Gau et al (2015)

Answer 8

• 6 males given EPO to get to 50% Hct

- EPO increase mitochondrial fat oxidation (9%) but not systemic fat oxidation

Question 9

Wilkerson et al (2015)

Answer 9

• 15 subjects, EPO and CON, weekly injections for 4 weeks
• No difference in oxygen uptake kinetics with/without EPO
• EPO group increase TTE and intensity of exercise nut not oxygen uptake kinetics

Question 10

Health risks of EPO

Answer 10

• Increased risk of blood clotting
• Elevations in systolic blood pressure
• Compromised thermoregulatory system
• Dehydration
• Fall in iron indicated by fall in ferritin (Birkland et al, 2000)