Comparison of dietary and smoking habit changes in physical fitness improvers and nonimprovers.

Changes in dietary, smoking, and alcohol intake habits of men who voluntarily increased their physical fitness level (n = 532) were compared with men who did not increase physical fitness (n = 390). These men were middle-aged (average age = 43 years), initially sedentary and free of disease, and had been examined twice at a preventive medicine clinic within a 1- to 6-year period. Subjects were retrospectively assigned to two fitness groups--improvers and nonimprovers--based on changes in treadmill performance between baseline and follow-up examinations. Fifteen lifestyle variables were assessed by questionnaire and evaluated for change. At baseline the two groups were similar in demographic variables and diet, differing significantly only in follow-up interval (P less than 0.001), treadmill time (P less than 0.001), whole milk consumption (P less than 0.003), and smoking (P less than 0.001). At follow-up, positive changes in health habits were seen for both groups. Statistically significant differences in health habit change between the groups were seen only for beef (P less than 0.003) and coffee (P less than 0.003) consumption (consumption of both decreasing in more improvers than nonimprovers). Smokers at baseline were less likely to improve their physical fitness. We concluded that individuals who voluntarily increased their physical fitness level were not more likely to change their dietary and alcohol habits than persons who maintained a more sedentary lifestyle.