L15 -measuring e intensity

Question 1

why is measuring e intensity valuable? 4

Answer 1

sustainable exercise (in training, in performance and in fitness testing)

Safety of exercise - in unscreened inactive, or clinical populations.
Severity/progression/management of disease - e.g., onset of TBI or angina symptoms.

Nature and magnitude of stimulus for adaptation. But it’s the most difficult exercise training parameter to quantify. i.e., frequency, time and type are easy. Is also highly contested as to pros and cons of diff intensities.

Question 2

ventilatory thresholds as a measure of ex intensity

Answer 2

VT1 - increase in VE/VO2. indicating prolonged exercise, ST motor units.

VT2 - steady state upto here, espically if fit.

The slope of VE/VO2
also useful indicator of ventilatory efficiency
= Ventilatory equivalent of oxygen, i.e., how much VE needed for each L O2used

Question 3

what does incease in VE/VCO2 indicate

Answer 3

Whereas, ↑ in VE/VCO2
indicates severe exercise; heavy motor unit recruitment, glycolysis and imminent fatigue.

Question 4

why can anaerobic threshold be a confusing term?

Answer 4

can refer to VT1 or usually VT2.
upwards inflections in VE and lactate can happen for many reasons.
thresholds can be extremely hard to identify and interpurt.

Question 5

why beware of intensity zones from smart watches?

Answer 5

mostly not validated indicators of intensity, whether for easy, sustainable or indicating CHO burning and fitness outcomes.

Question 6

what are two other useful measures of exercise intensity.

Answer 6

RER - respiratory exchange ratio.

and METS (activity met rate)/(resting met rate (RMR))

1 MET = RMR around 3.5mL/min/kg, therefor mets are just mulitples of RMR

Question 7

RPE

Answer 7

ratings of perceived exertion (RPE) how you are feeling 6-20.

Scales relate to physiol strain, regardless of fitness
May be at least as valid as any techno zones used!

Question 8

what three ways is HR used to indicate intensity.

Answer 8

1. heart rate (bpm)
   easy, intuitive
2. relative to max
   %HRmax = HR /HRmax* 100.
   Better indicator of relative exertion
3. ; %HRR = (HR - HRrest) / (HRmax – HRrest)* 100
   Excellent indicator of exertion

Question 9

exrcise economy

Answer 9

Energy expended to maintain constant speed
or per unit distance travelled.

Question 10

Efficiency

Answer 10

Metabolic cost of work; WR / MR *100 (%)
 Gross and Net efficiency both useful.
 Only possible if know WR, so economy is a
more versatile measure than efficiency is.

Question 11

factors that influence economy and efficieny?

Answer 11

speed of movement
exercise of work rate
fibre compostition of muscles
training status
and posture and familiarity w activity or ergometer.