Conditions:
(1) The person is walking at a constant speed of at least 50 meters per minute.
(2) The equation can be used at speeds over 100 m/min if the person is truly walking.
oxygen uptake in mL per kg per min =
= (resting oxygen uptake) + (horizontal oxygen uptake) + (vertical oxygen uptake)
horizontal oxygen uptake =
= 0.1 * (walking speed in meters per minute)
vertical oxygen uptake =
= 1.8 * (walking speed in meters per minute) * (grade)
where:
• The resting oxygen uptake is 3.5 mL per kg per min (1 MET).
• The 0.1 factor in the horizontal oxygen uptake is the regression constant for converting m/min to mL per kg per min.
• The 1.8 factor in the vertical oxygen uptake is the regression constant for converting m/min to mL per kg per min.
• The grade is the percent incline expressed as a decimal (for example, an X% incline is expressed as 0.0X).
• The vertical grade = 0 if (a) the walking is done on a level surface, (b) the person starts and ends walking at the same point.
