Lab 1 Flashcards
What is work and what are the three types of work
Work is the transfer of energy
- chemical work = ATP biosynthesis
- cellular work = active transport
- mechanical work = accomplished with muscular contractions
what is the equation to find work? SI units?
Work (J) = force (N) x distance (m)
What is energy
capacity to do work –humans transform chemical energy from food to perform work (measured in Calories)
What is power
rate of work done (power = work/time), rate of transforming metabolic energy to physical performance
ie. aerobic or anerobic
power
SI unit is watt (W) or kcal/min, or kgm/min, or kpm/min
how do you convert kgm or kpm to SI unit joule
for every mass of 1 kg must be multiplied by acceleration due to gravity (9.81 m/s2)
What are absolute terms for physiological and performance data
actual measured values with units
- ie. 80kg, 10m, 300 W, 10 L*min-1 rate of VO2
What are relative terms for physiological and performance data
data expressed in relation to another value (usually in relation to body mass)
- ie. a 50 kg subject is exercising at an absolute rate of oxygen consumption of 1L/min
Absolute intensity can be expressed as what
percent peak power output
10 mph as % of peak running speed
Exercise intensity can be expressed in absolute, relative or both terms
both – =10 Lmin-1or 10 L/minkg
What is a graded exercise test
work rate changes during the test and is usually an independent variable
for graded exercise test on cycle ergometer, subject exercise for 3 stages at 50, 100, and 150 W for 4 minutes per stage
on treadmill, subject run at constant speed but increase grade by 1% every 2 minutes or run at fixed grade but speed change every 2 minutes
What is a constant work exercise test
work rate remains fixed throughout the test
time is usually independent variable
ie. interested in monitoring HR response in subject over 30 minute exercise bout at fixed work rate
what is steady state of physiological parameters
physiological parameters become stable for an extended amount of time
some exercise intensities or factors may prevent stea
True or False all constant work rate exercise is steady state
false
what is non-steady state of physiological parameters
whenever a parameter is systematically changing over time and always occur at the initial transition to a new work rate as it take time for physiological parameters such as HR and VO2 to reach steady state
What is function in exercise physiology
WHY something happens
- HR increases to deliver more O2 to working muscle
What is mechanism in exercise physiology
HOW something happens
HR increased through parasympathetic withdrawl and increased sympathetic nerve activity
What is energy
the capacity to do work measured in J and cal
- humans convert PE (food) into chemical, cellular, and mechanical work
What is mechanical work
Mechanical work = foce * distnace measured in J, kcal, kilopond-meters, kilogram meters
How much work (J) does it take to lift a 10kg weight a distance of 2 meters
Mechanical work = force * distance
force = mass * acceleration = 10kg *9.81m/s^2 = 98.1 N
distance = 2 meters
Mechanical work = 98.1N * 2m = 196.2 J
How much work (kgm or kpm) does it take to lift a 10kg weight a distance of 2 meters
mechanical energy = force * distance
force = 10kg
distance = 2m
1kgm=1kpm
mechanical energy = 10kg *2 meters = 2kgm = 20 kpm
What is power and what is the equation associated with it and units
Power = work rate = work (J) / time (sec)
measured in Watts, kcal/min, kgm/min
How much power (W) does it take to perform 20,000 joules of work in 60 seconds
Power = work / time
time = 60 seconds
Work = 20,000 J
1 watt = 1J/s
power = 20,000J/60 sec =333.33 J/s = 333.33 W
A stationary cycle allows accurate measurement of what?
accurate measurement of work performed; friction based; 6 m/rev
Using 1.5kg (14.7N) resistance, 6m/rev, and 60 rev/min for 10 minutes of exercise determine total work and total power
Total Work: force * distance
14.7 N * (6m/rev * 60 rev/min * 10 minutes) = 52,920 J total work
OR 1.5kg * (6m/rev * 60 rev/min * 10 minutes) = 5400 kgm
Total Power: work / time
52,920 J / (10 minutes * 60 seconds) = 88.2 watts OR
5400 kgm / (10 minutes) = 540 kgm/min * (1W / 6kgm/min) = 90 W
