Exam 2 Ch 11

Question 1

Point at which blood lactate accumulation increases markedly

Lactate production rate > lactate clearance rate

Answer 1

Lactate threshold

Question 2

EPOC

Answer 2

O2 consumed > O2 demand in early recovery.
Body has to recover and replenish ATP/PCr stores, convert lactate to glycogen etc. Body still works harder for a little bit after exercise during recovery

Question 3

Decrements in muscular performance with continued effort, accompanied by sensations of tiredness

Answer 3

Fatigue

Question 4

Inability to maintain required power output to continue muscular work at given intensity

Answer 4

Fatigue

Question 5

Glycogen depletion

Answer 5

glycogen reserves are limited and get depleted quickly.
Depleted more quickly with high intensity
Depleted more quickly during first few minutes of exercise

Question 6

Certain rate of muscle glycogenolysis required to maintain…

Answer 6

NADH production in krebs cycle
Electron transport chain activity
No glycogen = inhibited substrate oxidation

Question 7

True or false
Fats burn in a carbohydrate flame

Answer 7

true

Question 8

Heat and how it alters metabolic rate

Answer 8

increases rate of carbohydrate utilization.
Hastens glycogen depletion
High muscle temp may impair muscle function

Question 9

Time to exhaustion is longest at what temp
when is it the shortest

Answer 9

Longest at 11 C
Shortest at 31 C

Question 10

what does H+ accumulation cause

Answer 10

decrease in muscle pH
can mess with muscle contraction

Question 11

If pH =6.4 what happens

Answer 11

prevents further glycogen breakdown

Question 12

what accumulates in mitochondria during prolonged exercise

Answer 12

Ca2+

Question 13

what can cause failure at the neruomuscular junction

Answer 13

reduced ACh synthesis and release
altered ACh breakdown in synapse
increase in muscle fiber stimulus threshold
altered muscle resting membrane potential