# Jonathan is a 34 year old male whose heart rate varies little from rest to exercise. He has VO2 max ml/min/kg. His Dr referred him to the facility for exercise training and wants him to begin at an...

Jonathan is a 34 year old male whose heart rate varies little from rest to exercise. He has VO2 max ml/min/kg. His Dr referred him to the facility for exercise training and wants him to begin at an intensity between 40% and 60% of VO2 reserve. You have found that Mr. P walks comfortabl at 2.5 mph.

What treadmill grades would allow him to exercise at the desired intensity range??

krobertello | Student

Although you did not list the resting VO2, we can assume it is 3.5 ml/kg/min, and therefore his VO2 max  is 10 times higher at 35 ml/kg/min. Next you would subtract your VO2 resting from your VO2 max like this: 35-3.5=31.5 ml/kg/min = VO2R (VO2 reserve). Next you would factor in the percent of VO2R you would like to train Jonathan. The target exercise range of 40-60% would be calculated by multiplying the VO2R while adding in the resting VO2:

(31.5 * .40) + 3.5 = 16.1 ml/kg/min

(31.5 *.60) + 3.5 = 22.4 ml/kg/min

We can divide the range totals by 3.5 to find METs for exercise prescription:

16.1/3.5=4.6 METs

22.4/3.5= 6.4 METs

A speed of 3 miles/hour at a grade of 2.5 would average 4.6 METs. From this point, he could increase speed and grade up to 4 miles/hour and 4 respectively to average 6.4 METs.