Question

1. The lactate threshold is when…

a. there is a dramatic surge in accumulation of lactate

b. there is a rise of more than .5 to 1 mmol/L in a non-linear fashion

c. an untrained subject reaches 65 to 80% of their VO2 max

d. a trained subject reaches a 65 to 80% of their VO2 max

2. When is lactate accumulation least likely?

a. during aerobic metabolism

b. during oxygen deficit

c. during glycolysis

d. during lactate threshold

3. EPOC remains elevated due to all of the following but…

a. increased aerobic metabolism

b. conversion of lactate to glucose

c. increased body temperature

d. restored blood oxygen levels

4. Lactate is produced during which part of exercise?

a. Aerobic metabolism

b. Oxygen deficit

c. Gluconeogenesis

d. EPOC

5. Lactate is a byproduct of which type of metabolism? Lactate can also be used as a fuel source by converting lactate to glucose via _____ .

a. Krebs cycle

b. oxygen deficit

c. lactate threshold

d. gluconeogenesis

Answer 1

1.a. there is a dramatic surge in accumulation of lactate.

During high intensity exercise,lactate accumulation in the blood occurs at a rapid rate than elimination which is defined as Lactate Threshold. Untrained persons can have lactate threshold when 50-60% of their VO₂ max is reached.Trained persons can have lactate threshold when 80-90% of their VO₂ max is reached. Threshold can also occur when there is a non-linear increase of atleast 1mmol/L of blood lactate ,according to Coyle(1983).

2.a. during aerobic metabolism

During glycolysis,oxygen deficit and lactate threshold,there will be more lactate accumulation.

3.b. conversion of lactate to glucose

Energy present in lactate is less than energy level in glucose.So EPOC will be low.

4.b. Oxygen deficit

When there is less oxygen,pyruvate in our body will be converted into lactate. In aerobic metabolism,gluconeogenesis and EPOC, sufficient oxygen will be present.

5.Lactate is a byproduct of glycolysis metabolism.

5d. gluconeogenesis

Lactate to glucose conversion occurs by gluconeogenesis. The fuel source of krebs cycle are fats and carbohydrates.In oxygen deficiency, lactate is produced but is not converted to glucose. During lactate threshold also, no conversion of lactate to glucose happens.