THE EFFECT OF SMOKING AND LIGHT ACTIVITY ON METABOLISM IN MEN

This experiment examined the metabolic effects of smoking during rest and light activity under naturalistic conditions. Thirty-nine male sub jects first completed a submaximal graded exercise treadmill test to s tandardize activity level. Then 3 groups of subjects-smokers smoking ( SS), smokers not smoking (SNS), and nonsmokers (NS)-were exposed to 3 stages of rest or 3 stages of light activity with order of rest or act ivity randomly determined over 2 different days. Energy expenditure wa s monitored continuously during these sessions. Significant increases in smokers' energy expenditure were observed during light activity whe n compared with smokers not smoking and nonsmokers. No differences wer e identified among groups at rest. These findings strengthen the concl usion that smoking or its components contribute to metabolic changes d uring typical levels of daily activity and suggest a mechanism for the frequently observed relationship between smoking status and bodyweigh t.