Lactate sampling, Respiratory Exchange Ratio and Indirect Calorimetry

Question 1

What is lactate sampling?

Answer 1

• A process where blood samples are taken in order to measure the level of lactate in the blood.

Question 2

What does a blood lactate reading tell us?

Answer 2

• The reading will tell us the intensity the athlete is working at.
• It is far more accurate than using heart rate to measure the intensity of training.

Question 3

What is a lactate sample used for? (Pt.1)

Answer 3

• Ensure training is at the right intensity.
  
  • Too much training at or above your lactate threshold can lead to over training.
  • Training too far below will lead to a training plateau where no improvement is made.
• Used in determining training zones.

Question 4

What is a lactate sample used for? (Pt.2)

Answer 4

• Monitor training programmes.
  
  • Following a training regime you would expect to see an athletes lactate reading to decrease.
• Measure an athletes OBLA.

Question 5

Define Respiratory exchange ratio

Answer 5

• Is the ratio of the volume of CO2 expired per minute to the volume of O2 consumed per minute.

Question 6

How is RER expressed?

Answer 6

• This ratio is expressed as a value (usually between 0.7 and 1.1).
• The higher the value, the more CO2 is being exhaled.

Anaerobic exercises are more intense and require your body to generate energy faster than the cardiovascular system can provide it.
Sprinting, and high-intensity interval workouts are examples of anaerobic exercises that force your body to use more oxygen.

Question 7

What does an RER reading tell us?

Answer 7

• Determines which energy source is being oxidised.
• This is called the Recipient Quotient (RQ), which is an indicator of which fuel (carbohydrate or fat) is being metabolised to supply the body with energy.

Question 8

RER values

Answer 8

• 0.7 indicates that the predominant energy source is fats.
• 0.85 indicates a mix of carbohydrates and fats as the main energy source.
• 1.0 indicates that carbohydrate is the sole source of fuel.
• > 1.0 indicates anaerobic respiration

Question 9

What is an RER reading used for?

Answer 9

• Coaches can use it to tell them whether their athletes are working aerobically or anaerobically.
• Measures intensity.
• Can help identify training zones.

Disadvantage: RER can only be measured using gas analysis equipment in a laboratory.

Question 10

What is Indirect Calorimetry?

Answer 10

• A technique that provides an accurate estimate of energy expenditure through gas exchange.

Question 11

What does it measure?

Answer 11

• It measures how much CO2 is produced and how much O2 is used.

Question 12

Other info about IC…..

Answer 12

• Happens at a cellular level.
• Very reliable and gives a precise calculation of VO2 max.