Biochemical Basis of Sports Performance (Aerobic metabolism)

Question 1

VO2max can distinguish between elite athletes in the marathon?

Answer 1

False A high VO2max is a prerequisite for success, but the fractional utilisation of VO2max is more important for events > 20 min in duration

Question 2

What is the Maximal Lactate Steady State (MLSS), and how is it determined?

Answer 2

Determined by performing multiple exercise bouts with blood lactate stability over time

Question 3

What is the estimated rate of ATP production (mmol/kg muscle / sec) for FTA oxidation?

Answer 3

1.5

Question 4

How would you classify the cardiorespiratory fitness level of a 30-year-old female with a VO2max of 55 ml/kg/min?

Answer 4

Superior

Question 5

Which of the following is NOT a key stage in the complete oxidation of a molecule of glucose?

Answer 5

b-oxidation

Question 6

What is Maximal Aerobic Speed (MAS)?

Answer 6

The speed at which maximal oxygen uptake is reached

Question 7

What is the correct definition of VO2max in exercise physiology?

Answer 7

The maximum volume of oxygen consumed by the body each minute during large muscle group exercise at sea level

Question 8

Stage 2 of aerobic metabolism is usually referred to as the link reaction and describes the formation of which molecule from 2 molecules of pyruvate?

Answer 8

Acetyl CoA

Question 9

According to Bellenger et al (2015) the average speed determined over a _____ time trial is the best predictor of maximal aerobic speed

Answer 9

2km

Question 10

During incremental exercise, RER may increase from ____ to ____ reflecting the change in substrate utilization from predominantly fat to solely CHO.

Answer 10

0.8- 1.0

Question 11

What physiological concept marks the boundary between heavy- and severe-intensity exercise?

Answer 11

Critical power (CP)

Question 12

What physiological factors influence your VO2max?

Answer 12

Pulmonary diffusion capacity
Cardiac output
Haemoglobin levels
Muscle fibre type

Question 13

Why is it valuable for an exercise physiologist to measure an athlete’s speed or cycling power at maximal metabolic steady state?

Answer 13

To predict the athletes performance potential and race pace

Question 14

What energy system is predominantly utilised when exercising below the ventilatory threshold?

Answer 14

Aerobic metabolism

Question 15

At the ventilatory threshold, there is a disproportionate increase in ventilation relative to oxygen consumption caused by?

Answer 15

Increased bicarbonate buffering of lactate & H+

Question 16

How would you classify the cardiorespiratory fitness level of a 20-year-old male with a VO2max of 32 ml/kg/min?

Answer 16

Poor

Question 17

Lactate threshold occurs at approximately _____ of VO2max in untrained individuals and at approximately ____ of VO2max in endurance-trained individuals, which allows a higher workload without an increase in blood lactic acid concentration.

Answer 17

50-60%, 65-80%

Question 18

Which of the following are important enzymes in the aerobic respiration of triacylglycerol?

Answer 18

Lipoprotein lipase, adipose triglyceride lipase, monoacylglycerol lipase, acyl CoA synthase, citrate synthase

Question 19

The conversion of activated fatty acids to acetyl-CoA that takes place in the mitochondrial matrix is known as what?

Answer 19

β-oxidation

Question 20

Considering a 70-kg man expending energy at a rate of 80 kJ/min (exercising at ~70% VO2max), how long would muscle glycogen stores last?

Answer 20

Approximately 60 minutes

Question 21

Which of the following adaptations occurs with high training volume at low intensity (~ 40% VO2max)?

Answer 21

Mitochondrial biogenesis

Question 22

Success is notably influenced by having a high VO2max, especially in which sport or event?

Answer 22

1500m track running

Question 23

How is the Respiratory Exchange Ratio (RER) determined?

Answer 23

Carbon dioxide production divided by oxygen consumption

Question 24

What does the term “fractional capacity of VO2max” refer to in exercise physiology?

Answer 24

The proportion of VO2max utilized during submaximal exercise

Question 25

In a study examining professional soccer players, what correlation was found between VO2 max and repeated sprint ability (average time for repeated sprints)

Answer 25

Negative

Question 26

What is considered the primary factor determining lactate threshold in exercise physiology?

Answer 26

The oxidative capacity of the muscle

Question 27

What is Anaerobic Speed Reserve (ASR)?

Answer 27

The speed range between maximal sprinting speed and maximal aerobic speed.

Question 28

How is Critical Speed (CS) often estimated in team players?

Answer 28

By calculating a percentage of their Maximal Aerobic Speed (MAS).

Question 29

An endurance-trained individual will metabolise a higher percentage of fatty acids when running at the same absolute workload or race pace compared with an untrained individual due to what training adaptation?

Answer 29

Increases in the level of enzymes of Krebs cycle and ETC Increases in the levels of enzymes of beta oxidation

Question 30

Having a high VO2max can improve our repeated sprint ability?

Answer 30

True aerobic capacity is an important factor influencing recovery between repeated sprints is likely related to i) efficient restoration of PCr and ATP stores from inorganic phosphate post exercise and ii) improved ability to tolerate, remove, and buffer hydrogen ions (H+) from the working muscle

Question 31

The Electron Transport chain cannot continue to synthesise ATP unless which molecule is available to act as the final electron acceptor?

Answer 31

Oxygen

Question 32

What physiological factors can determine your VO2 max?

Answer 32

Cardiac Output Oxygen carrying capacity of the blood Capillary density Muscle fibre type distribution

Question 33

Which factors can affect the relative percentage of fat or carbohydrates an individual utilises as an energy source?

Answer 33

Training, diet and genetic differences

Question 34

What blood lactate concentration is commonly used to reflect the Onset of Blood Lactate Accumulation (OBLA) during exercise?

Answer 34

4 mmol/L