Exercise Intensity Domains

Question 1

Define exercise intensity

Answer 1

How we categorise an ind. physiological response to external work.

Question 2

Define normalising

Answer 2

Attempt to ensure the ind. experience an equivalent physiological demand.

Question 3

When is it important to ‘normalise’ exercise intensity?

Answer 3

In any scientific study when measuring the physiological or perceptual impact of an intervention. i.e substance utilisation

When designing effective exercises training prog. i.e to stimulate adaptation

Question 4

Why account for exercise intensity?

Answer 4

To ensure we’ve got participants exposed to the same physiological demand.

Question 5

What can obscure real differences in scientific experiments?

Answer 5

Intra + inter ind differences or variability in results.

Question 6

Lactate threshold occurrence varies widely between ind.

Between what %

Answer 6

30-85% VO2 max

Question 7

What are the 4 exercise intensity domains accepted by Burnley & Jones, 2007?

Answer 7

Moderate

Heavy

Severe

Extreme

– ONLY easily classifiable during constant work-rate exercise.

Intermittent exercise inv. dynamic transitions between the exercise intensity domains.

Question 8

Burnley & Jones, 2007

Moderate exercise intensity

Answer 8

All intensities below the LT

Question 9

Burnley & Jones, 2007

Heavy exercise intensity

Answer 9

Above LT + below max steady state

Question 10

Burnley & Jones, 2007

Severe exercise intensity

Answer 10

Above max steady state

Achieving VO2 max

Question 11

Burnley & Jones, 2007

Extreme exercise intensity

Answer 11

Exhaustion before VO2 max

Question 12

What is the VO2 slow component?

Answer 12

A slow component

Evident after 2-3 mins

Question 13

Where is the VO2 slow component found?

Answer 13

ONLY above the LT

i.e never during moderate intensity exercise

Question 14

What happens to the V02 slow component during heavy intensity exercise?

Answer 14

Eventually levels off (steady state)

Question 15

What happens to the V02 slow component during severe intensity exercise?

Answer 15

Projects to VO2 max

NO steady state

Question 16

What happens to the V02 slow component during extreme intensity exercise?

Answer 16

Exercise in this domain isn’t typically long enough for the slow component to be determined.

Question 17

What is the most likely explanation of the VO2 slow component?

Answer 17

That its related to additional fibres being recruited throughout exercise to replace those that have become fatigued.

These fibres are therefore contributing to forced prod + O2 requirement = resulting in continued drift upwards in the O2 uptake response.

Question 18

What was the 1st study to provide direct evidence that type 2 fibre recruitment is associated with the VO2 slow component?

Answer 18

Krustup et al. 2004

Question 19

Definition for cycling economy or gain

Answer 19

Amount of O2 its costing us relative to the work load

Question 20

How is cycling economy or gain calculated?

Answer 20

Change in VO2 / change in work load

Question 21

What is the lowest available power output on a standard ergometer?

Answer 21

20 Watts (even if the ergometer says 0)

Question 22

How is change in work load calculated?

Answer 22

End power - Baseline power

Question 23

Moderate exercise in its simplest description

Answer 23

All work rates below LT

Blood lactate is NOT elevated

VO2 ⬆️ at ~10ml/min/W

Question 24

For how long can moderate exercise be continued for?

Answer 24

~4hrs

Question 25

Reasons for fatigue in moderate exercise

Answer 25

Muscle glycogen depletion Muscle damage ⬆️ core temp.

Question 26

HR in moderate exercise

Answer 26

Steady state attained w/in 3 mins

Question 27

Blood lactate in moderate exercise

Answer 27

Not elevated above baseline/resting values

Question 28

What happens w/ VO2 in heavy exercise intensity

Answer 28

After 2-3 mins VO2 continues to ⬆️ via the slow component

Question 29

What happens as the heavy exercise is conducted close to the lactate threshold?

Answer 29

The smaller the VO2 slow component

Question 30

What is crucial to remember about heavy exercise?

Answer 30

That even if exercise is completed to exhaustion, VO2 remains sub-maximal. Steady state will be attained.

Question 31

What sports are performed predominantly w/in the heavy domain?

Answer 31

Many endurance events Incl. marathon

Question 32

How long can heavy intensity exercise last if at a constant work rate?

Answer 32

~30-120 mins

Question 33

Causes of fatigue from heavy exercise intensity

Answer 33

Combination of metabolite accumulation + substrate availability

Question 34

HR in heavy exercise intensity

Answer 34

Delayed Elevated to a steady state

Question 35

Blood lactate for heavy intensity exercise

Answer 35

Elevated above resting values but a SS is attained.

Question 36

Which is the ONLY domain in which VO2 max is attained?

Answer 36

Severe

Question 37

In severe exercise what causes the VO2 to reach its Max?

Answer 37

The VO2 slow component

Question 38

Do you see a steady state in severe exercise?

Answer 38

NO

Question 39

What are the 2 reasons for why exercise in the severe domain is unique?

Answer 39

Has a wide range of work rates for which VO2 max can be attained. Exercise tolerance is limited but also predictable

Question 40

Duration for severe exercise intensity

Answer 40

2-~30 mins

Question 41

Fatigue in severe exercise intensity

Answer 41

PCr depletion Accumulation of fatiguing metabolites (Pi, H+)

Question 42

HR in severe exercise intensity

Answer 42

No steady state Continues to rise until max HR is achieved

Question 43

Blood lactate in severe exercise intensity

Answer 43

No steady state Continues to rise until exhaustion

Question 44

Time to exhaustion for extreme exercise intensity domain

Answer 44

<90s

Question 45

Fatigue reasons for extreme exercise intensity

Answer 45

PCr depletion + accumulation of fatiguing metabolites

Question 46

HR for extreme exercise intensity

Answer 46

No steady state Exercise stops before HR max is attained

Question 47

Blood lactate for extreme exercise intensity

Answer 47

No steady state Value may be surprisingly low due to short duration of exercise

Question 48

What is a ‘step’ exercise test.

Answer 48

Refers to the way in which the load has been delivered. Usually = an immediate ⬆️ in external workload from unloaded cycling to a higher power output, allowing us to track the responses of physiological variables as they adjust to the ⬆️ metabolic requirement.

Question 49

Why do we perform 3-minutes of ‘unloaded’ exercise prior to the addition of the load?

Answer 49

Allows perf to establish a 'baseline' in physiological variables. Can then correctly calculate extents to which the variables have changed.

Question 50

Why do we select 6-minutes for the loaded exercise?

Answer 50

Should be long enough to determine the intensity domain from our physiological measures (except cases that are right on the borderline).

Question 51

What can cycling economy tell us?

Answer 51

Higher gain is usually indicative of participant being above LT, where we will encounter the O2 uptake SC (an additional oxygen cost associated with additional motor unit recruitment).

Question 52

How do we estimate the oxygen uptake slow component, and what does it indicate?

Answer 52

Value at end exercise - value at 3 mins of unloaded cycling. Higher the number, the larger the slow component. = Ind is consuming more O2 for a given work load than would have been predicted from the response to lower intensity exercise.

Question 53

Which exercise intensity domain(s) result in a steady state in oxygen uptake, heart rate, and blood lactate?

Answer 53

Moderate and heavy (with the latter being a delayed and elevated steady state)

Question 54

Which exercise intensity domain(s) result in the attainment of maximal oxygen uptake?

Answer 54

Severe - the only domain when completed to exhaustion which results maximal oxygen uptake.

Question 55

Why is it important to account for exercise intensity when designing scientific experiments?

Answer 55

The body responds differently to different exercise intensities, with different mechanisms explaining fatigue. Inter-individual differences in the physiological responses can confound the results of experiments.

Question 56

What underpins the variance in physiological responses at different intensities?

Answer 56

Occurrence of LT, GE threshold + MSS

Question 57

What will happen to muscle PCr levels after exhaustive exercise above the MSS?

Answer 57

Sig reduction compared to resting levels.

Question 58

What exercise would elicit the biggest reduction in muscle glycogen conc if it continued to exhaustion?

Answer 58

Exercise below LT

Question 59

What would we expect blood lactate levels to be at the end of 6-min of moderate exercise?

Answer 59

Equal to resting levels

Question 60

What is the upper boundary of the heavy domain?

Answer 60

Highest work rate where lactate stabilises.