LACTATE, THE FATE OF LACTATE & THRESHOLDS

Question 1

DIFFERENCES BEWTEEN AEROBIC + ANAEROBIC TRAINING

Answer 1

AEROBIC
- improved central (blood flow to brain, spinal cord and other vital organs) and peripheral (muscles, skin) blood flow

• enhances the capacity of muscle fibres (type 1) to generate ATP

ANAEROBIC
- increased short-term, high-intensity endurance capacity (anaerobic capacity)

• increased anaerobic metabolic function (increase the rate of ATP resynthesis through the breakdown of PC and muscle glycogen also associated with strength, power/ explosive)
• increased tolerance for acid-base imbalances during highly intense effort
• increase ability to utilise, tolerate and clear the accumulation of metabolic waste

Question 2

ANAEROBIC THRESHOLD

Answer 2

point during exercise where body changes from aerobic to anaerobic metabolism/ exercise for energy

Question 3

AEROBIC THRESHOLD

Answer 3

point during exercise when your body must switch from anaerobic to aerobic metabolism to produce energy

Question 4

LACTATE THRESHOLD

Answer 4

the point at which, during incremental exercise, lactate builds up in the blood stream at a level that is higher than resting values. the lactate turn point is where OBLA occurs

OBLA = Onset of Blood Lactate Accumulation

lactate threshold is a good predictor of submaximal fitness

Question 5

BENEFITS OF TRAINING NEAR THE ANAEROBIC/ LACTATE THRESHOLD

Answer 5

• improve its use of lactate as an energy source (via cori-cycle)
• improve its clearance mechanisms (removal of lactate & H+)
• improve the buffering capacity (the ability of muscles to neutralise the acid that accumulates in them during high-intensity exercise) to negate the fatiguing effects of metabolic waste products (H+) accumulation

Question 6

UCB

Answer 6

Utilise

Clearance

Buffering

Question 7

IMMEDIATE PHYSIOLOGICAL EFFECTS OF LACTIC ACID WITHIN WORKING MUSCLES

Answer 7

• increased hydrogen ions concentration (pH decrease)
• muscle fatigue and discomfort
• impaired glycolysis and ATP production
• inhibition of enzyme activity
• oxygen debt (EPOC) excess post exercise oxygen consumption

Question 8

CORI-CYCLE

Answer 8

the process by which the body manages lactic acid during exercise. it involves the muscles and the liver working together to keep energy levels up and prevent fatigue.
lactic acid changes back into pyruvate then glucose

Question 9

FATE OF LACTATE

Answer 9

post exercise, lactic acid is converted back into pyruvic acid as part of the recovery process:

(1) (50-75%) pyruvate is oxidised into CO2 and H2O ( enters mitochondria and be used in the krebs cycle and electron transport chain)

(2) (10-20%) is converted into glucose and glycogen (via cori-cycle)

(3) (5-10%) is converted into protein

(4) converted into urine and sweat