Age-Related Decline in Cardiorespiratory Fitness among Career Firefighters: Modification by Physical Activity and Adiposity

Table 2

Linear regression model describing Cardiorespiratory fitness (maximal achieved METS) (in randomly assigned training set 𝑛=405).

Variable	Parameter estimate	Standard error	𝑃 value
Age	−0.05886	0.01031	<0.0001
BMI	−0.21131	0.01994	<0.0001
Total weekly duration	0.00845	0.00232	0.0003
Total weekly duration squared	−0.00001297	0.000000569	0.0233
Duration of weight lifting	0.18937	0.06393	0.0032
Intensity of exercise	0.21331	0.12362	0.0878