LONG-TERM USE OF SMOKELESS TOBACCO AND PHYSICAL PERFORMANCE IN MIDDLE-AGED MEN

To determine the influence of prolonged nicotine exposure on maximal p hysical working capacity, a study of clinical measures of physical fit ness and cardiovascular response to exercise was performed in 144 heal thy men, 35-60 years old, subdivided into smokeless tobacco users, smo kers and non-users of tobacco. Regular users of smokeless tobacco, wit h exposures of more than 20 years, showed similar maximal oxygen uptak e (mean 3.48 L min(-1), SD 0.49, n = 48) to non-users (mean 3.51 L min (-1), SD 0.51, n=65). In smokeless tobacco users, higher blood pressur e and heart rate values were observed at rest and at submaximal work, after exposure to tobacco shortly before the exercise test, but not at maximal work. However, significantly lower maximal oxygen uptake was found for smokers (mean 2.88 L min(-1) SD 0.49, n=31) compared with no nusers (P<0.001). Plasma concentration of cotinine, the main metabolit e of nicotine, was significantly higher in smokeless tobacco users (me an 347 ng mL(-1), SD 175, n=48) than in smokers (mean 253 ng mL(-1), S D 153, n=31, P < 0.001). The findings indicate that longterm use of sm okeless tobacco does not significantly influence exercise capacity in healthy, physically well-trained subjects.