L3 Assessment of Physical Performance

Question 1

What are the common SI units for the following:
Work
Power
Energy
Net efficiency

Answer 1

work = J –> joules
Power = W –> Watts
Energy = J
Net Efficiency = %

Question 2

How do you calculate work?

Answer 2

Work (J) = Force (N) X Distance (m)

Question 3

How do you calculate power?

Answer 3

Power (w) = Work(j) / Time(s)

Question 4

what are 3 examples of power tests?

Answer 4

Stair sprinting test
jumping power test
Wingate test - 30s sprint test

Question 5

How can short-term maximal anaerobic power be evaluated by the stair sprinting test?

Answer 5

Subjects run up stairs as fast as possible 3 steps at a time. Power output = body mass (kg) X vertical distance (m), all divided by time (s). Measured via electric switch mats on steps 3 and 9.

Question 6

How can the Wingate test be used to assess medium-term anaerobic power?

Answer 6

30s sprint test in 2 conditions
1) unloaded maximal pedalling with no resistance
2) resistance added
The load can be optimised

Question 7

Give a brief explanation of how work and power can be calculated through bench stepping

Answer 7

• step ups to a set rate.
  Measure weight of participant, how big the step up is and then how may steps per minute for how many minutes.
  Total work = (kg x gravity) X (step size x steps per min x mins)
  Power = total work / time (in seconds)

Question 8

Give a brief explanation of how work and power can be calculated through cycle ergometer exercise

Answer 8

Total work = (resistance in N) x (distance travelled per revolution) x (revs per minute) x (minutes)
Power = (total work) x time (s)

Question 9

Give a brief explanation of how work and power can be calculated through treadmill exercise

Answer 9

• must be going up a slope

total work = (body weight) X (vertical displacement = %grade x distance (distance per min x time) )
Power = work / time(s)

Question 10

Describe the concept behind the measurement of energy expenditure using direct calorimetry

Answer 10

You directly measure heat production.
Food –> burn food that heats the surrounding water
Human –> person in tank, measure water heat change but is expensive and labour intensive.

Question 11

Describe the concept behind the measurement of energy expenditure using indirect calorimetry

Answer 11

measuring O2 consumption, CO2 production and N2 balance. done through closed or open circuit spirometry

Question 12

How can oxygen consumption be measured using closed-circuit spirometry

Answer 12

participant breathes in and out of a tube that’s connected to a oxygen chamber. the co2 breathed out then moves into a soda lime chamber which absorbs the co2 and emits the O2 back into the o2 chamber that wasn’t used. O2 consumption is then recorded in the recording drum.
All works within a pulley system.

Question 13

How can oxygen consumption be measured using open-circuit spirometry

Answer 13

subject inhales normal air. then changes in o2% and co2 in expired air compared to the inspired air. Oxygen uptake then equals volume % of oxygen inspired minus volume percent oxygen expired.

Question 14

What are the negatives of using closed-circuit spirometry

Answer 14

bulky
time consuming
cant be used during dynamic movement

Question 15

provide a brief overview of the design of an incremental test to determine Vo2max.

Answer 15

include treadmill running, bench stepping, stationary cycling.
can be single, continuous 3-5 mins surpramaximal effort or progressive increments of effort

Question 16

Identify what criteria can be used to determine the validity of a Vo2 max test

Answer 16

sub max predictions, relationship between submax HR and VO2 uptake to assumed HR max. slope of this line reflects adequacy of CV response and aerobic fitness capacity

Question 17

list six factors that can affect VO2 max

Answer 17

mode of exercise
Heredity
State of training
Gender
Body size and composition
Age

Question 18

what is the relationship between heart rate and Vo2 during an incremental test and how may this be used to predict vo2 max?

Answer 18

positive relationship.
Line of best fit to max predicted heart rate, then see what the O2 consumption would be for this HR, this is predicted VO2 max

Question 19

explain what are the pitfalls associated with using an incremental test to assess VO2 max

Answer 19

the termination of the test can be influenced by motivational factors that don’t reflect physiologic strain.
it only gives you a prediction which can fall between 10 to 20% of the persons actual VO2max