Question

Determine the oxygen cost for an individual walking on a treadmill at 2.2 miles/hr up a 5 % grade How many calories (kcals) did this client expend? u o Determine the proper elevation required to elicit a VO of 18ml/kg/min if the tread mill speed is set at 3mph. Determine the proper elevation required to elicit a VO2 of 25ml/kg/min if the treadmill speed is set at 3.5 mph.

Answer 1

1.Ans: VO₂ = 0.1 ( speed) + 1.8 ( speed)( fractional grade) + 3.5

= 2.68 (speed) + .48(speed)(fractional grade) +3.5

=2.68 × 2.2 + .48 ×2.2× 5 + 3.5

= 5.896 + 5.28 + 3.5

= 14.68 ml/min/kg

Oxygen cost = 14.68 ml/min/kg

Calorific expenditure = VO₂ l/min × 5 kcal/ l

= 14.68 × mass in kg /1000 × 5 kcal/l

= 0.0734 × (mass in kg) kcal/min ( since body mass is not given the question)

2. Ans : We know that VO₂ = 3.5 + 2.68 ( speed ) + .48 ( speed)(fractional grade)

VO₂  and speed are given

Therefore , 18 ml/kg/min = 3.5 + 2.68×3 + .48 × 3 × grade

18 = 11.54 + 1.44 × grade

Elevation = 4.49%

3.Ans: Similarly substitute the given values in the above equation.

25ml/kg/min = 3.5 + 2.68 × 3.5 + 0.48 × 3.5 × grade

25 = 12.88 + 1.68 × grade

Elevation = 7.21%