A 160lb person who runs at 88 mph for 1 hr burns about 720 c

A 160-lb person who runs at 88 mph for 1 hr burns about 720 calories. The same person, walking at 44 mph for 90 min, burns about 240 calories. Suppose a 160-lb person runs at 88 mph for 75 min. How far would the person have to walk at 4 mph in order to burn the same number of calories as burned when running?

Solution

A 160-lb person who runs at 88 mph for 1 hour burns about 720 calories. Hence, a 160-lb person runs at 88 mph for 75 min burns 720*(75/60) = 900 calories (as 1 hour = 60 minutes). Also, the same person, walking at 4 mph for 90 min, burns about 240 calories so that, at this pace of walking, the person burns 240/90 = 8/3 calories per minute or, 1 calorie in 3/8 minute. Therefore, as this pace of walking the same person will burn 900 calories in 900*(3/8) = 337.5 minutes or 5 hours, 37 minutes, 30 seconds.