Domains of exercise (S1W6)

Question 1

What is critical power (CP)?

Answer 1

highest power output that can be maintained over time

Question 2

What is critical power (CP) related to?

Answer 2

maximum lactate steady state (MLSS)

• that’s the intensity where products don’t accumulate - can maintain over time
• critical power and MLSS describe more or less the same physiological state

Question 3

What is W’ (W prime)?

Answer 3

• our anaerobic energy store
• CP is intensity you can maintain over time to mainly aerobic
• above CP will be mainly anaerobic (W’)

Question 4

How do you calculate W’ (W prime)?

Answer 4

W’ = supra-CP x duration

Question 5

What is supra-CP?

Answer 5

• the energy between W’ and CP

- e.g. if an athlete’s CP is 300 W and we’re working at 600 W, then supra-CP is 300 W (600 - 300)

Question 6

What units is W’ in?

Answer 6

Joules (J)

Question 7

On a graph what two things would be found at basically the same point?

Answer 7

• critical power and maximum lactate steady state

- because they both more or less describe the same physiological state

Question 8

Why is critical power (CP) often a more applicable measure than VO2 max?

Answer 8

• because we rarely work at VO2 max

Question 9

Critical power and training

Answer 9

• training above CP will only allow for interval training because breaks needed as homeostasis can’t be ensured above CP

Question 10

What counts as the low intensity domain of exercise?

Answer 10

• anything below lactate threshold (LT) is regenerative low intensity training
• BLa < ~2mmol/L
• steady state after < 3 min

Question 11

What counts as the moderate intensity domain of exercise?

Answer 11

• between the lactate threshold (LT) and the MLSS/CP
• BLa elevated but stable at ~2 to 8mmol/L
• ~70-90% VO2max
• steady state achievable but will take longer

Question 12

What counts as the severe intensity domain of exercise?

Answer 12

• above the MLSS/CP
• BLa > ~2-8 mmol/L
• ~90% VO2max
• steady state not attainable - need breaks (interval training)

Question 13

When is steady state no longer achievable?

Answer 13

• 5% above critical power (CP)

Question 14

Explain a method for determining O2 uptake

Answer 14

• Breath by breath analysis
• Mask on with a turbine - turns one way when you. Breathe out and the other way when you breathe in
• Has a sensor that measures O2 concentrations and CO2 concentrations
• If the air is going in, it will measure 20.9% of O2 (breathing in room air)
• If air is going out, it will measure the O2 concentration in what you’re breathing out

Question 15

Why is breath by breath analysis of oxygen uptake kinetics useful?

Answer 15

• oxygen uptake kinetics differ for different exercise intensities and can help to define domains of exercise
• allows us to determine O2 uptake for every single breath
• allows us to draw a trace to identify the 3 distinct phases