Download - HPHE 4450 - Section 11
Outline
• What are prediction equations?
• How are they useful?
• Walking, running, cycling equations
• Determining calorie expenditure
Prediction equations allow us to predict the
oxygen uptake (VO2) of a person for a given
exercise session.
Used for a various types of exercise
Cycling, walking, running, stepping
We are using ACSM prediction equations
What Are Prediction Equations
Allows us to predict VO2
Allows us to determine the exercise
intensity that will elicit a known VO2.
Can estimate calorie expenditure
Uses of Prediction Equations
Review of Workload on Cycle
Workload is measured in:
kg • m • min-1 or Watts
Two factors can be adjusted:
Resistance on the flywheel (kg or kp)
Rate (RPM’s)
kg•m•min-1
= kg (6m/rev rev/min)
Conversion: 6 kg•m•min-1
= 1 Watt
Tom is pedalling at 60 RPM’s with a resistance of 2.5 kp.
What is the workload is kgm/min and Watts?
Kgm/min = 2.5 (6m/rev 60 rev/min)
Workload = 900 kgm/min
Watts = 900 kgm/min 1 Watt
6 kgm/min
Workload = 150 Watts
Example Problem
VO2 = (0.1 S) + (1.8 S G) + 3.5
Speed (m/min)
Speed (m/min)
Constant Constant
Constant
% Grade (decimal)
VO2 is mL/kg/min (Relative)
m/min = mph 26.82
ACSM Walking Prediction Equation
Used for speeds 1.9 to 3.7 mph
VO2 is mL/kg/min (Relative)
m/min = mph 26.82
ACSM Running Prediction Equation
VO2 = (0.2 S) + (0.9 S G) + 3.5
Speed (m/min)
Speed (m/min)
Constant Constant
Constant
% Grade (decimal)
Used for speeds > 5.0 mph
Determining the proper exercise
intensity to elicit a given VO2
Joe has a VO2max of 55 ml/kg/min and weighs
75 kg. What do we set the bike at so that he is
exercising at 70% of his VO2max?
Example
Solution
•Determine 70% of VO2max
•Solve prediction equation for kgm/min
•Pick an RPM and solve for resistance
(workload equation)
Practical Application
VO2 has to be in LO2/min
Getting from mLO2/kg/min to LO2/min Multiply VO2 in mLO2/kg/min by bodyweight and divide
by 1000 Ex: 40 mLO2/kg/min 60kg = 2400 mLO2/min
2400 mLO2/min 1000 = 2.400 LO2/min
Energy Expended Kcal = VO2 (LO2/min) * RER kcal Equiv. * minutes
Remember, if we don’t know RER kcal Equiv. then we use the value of 1 LO2/min = 5 kcal/min
Determining Energy Expenditure
Practical Application
Determining caloric expenditure for
an exercise session?
Example One
Bill, who weighs 83 kg, exercises on a cycle ergometer for 30
minutes at an resistance setting of 3.0 kg and 60 rpm. What
is his predicted total caloric expenditure for the exercise bout?
•Determine kgm/min and then determine predicted VO2.
•Multiply predicted VO2 (LO2/min) by 5 to get kcal/min
•Multiply kcal/min by 30 minutes to get total caloric expenditure
Solution