Cardiorespiratory fitness is widely recognized as a major co

Cardiorespiratory fitness is widely recognized as a major component of overall physical well-being. Direct measurement of maximal oxygen uptake (VO₂max) is the single best measure of such fitness, but direct measurement is time-consuming and expensive. It is therefore desirable to have a prediction equation for VO₂max in terms of easily obtained quantities. Consider the variables

y = VO₂max (L/min)
x₁ = weight (kg)
x₂ = age (yr)
x₃ = time necessary to walk 1 mile (min)
x₄ = heart rate at the end of the walk (beats/min)

Here is one possible model for male students, consistent with the information given in the article \"Validation of the Rockport Fitness Walking Test in College Males and Females\"

Solution

(a).Holding all other variables constant, a 1 kg increase in weight will result in a 0.01 L/min increase in VO₂max.

Holding all other variables constant, a 1 min increase in walk time will result in a 0.13 L/min decrease in VO₂max.

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(b)5.0 + 0.01*76 ? 0.05*24 ? 0.13*15 ? 0.01*138 = 1.23