lecture 22

Question 1

blood lactate durin light exercise

Answer 1

• Major energy system = aerobic metabolism
• Minimal contribution from anaerobic glycolysis
• Blood lactate accumulation is low
• 1-2 mM

Question 2

blood lactate and incremental exercise

Answer 2

• As exercise intensity increases, aerobic metabolism can no longer meet all the energy requirements of active muscle
• Energy from anaerobic glycolysis increases
  = increased = lactic acid begins to accumulate

Question 3

The lactate threshold

Answer 3

is the point where La just begins to increase to a level approx 1.0 mM above pre-exercise level

Question 4

the onset of blood lactate

Answer 4

is the point that blood lactate = 4mM (doesn’t account for individual differences).

Question 5

lactate threshold and buffering

Answer 5

As exercise intensity increases, anaerobic metabolism supplies more energy = lactic acid accumulates. Lactic acid dissociates to lactate & H+.
- H+ is buffered by bicarbonate

Question 6

moderate to heavy exercise

Answer 6

• VCO2 increases disproportionately to workload
• VE increases disproportionately with workload
• VO2 increases linearly with workload until near maximal levels of exercise

Question 7

how can you detect Vt

Answer 7

Graphing VE during incremental exercise and noting where VE increases disproportionately

Question 8

aerobic measures

Answer 8

• Gold standard measure of cardiovascular capacity.
• Maximum amount of oxygen that can be transported and utilised within the working muscle.
• Partially determined by genetic make-up (25 – 50%)
• Can be increased through training (5 – 20+%).

Question 9

VO2 peak

Answer 9

• If criteria not met then result represents a VO2peak

- VO2peak refers to the highest values of O2 consumption during a graded exercise test.

Question 10

factors affecting VO2 max

Answer 10

• heredity
• age
• gender