Association of Total and Differential White Blood Cell Counts with Physical Energy Expenditure

Abstract

Objective: To assess the association between physical energy expenditure and the total and differential white blood cell (WBC) counts which reflect systemic inflammation.

Methods: This study included 953 and 277 apparently healthy middle-aged men and women who were employed and had participated in a general health examination in 2006-2007. They completed a questionnaire regarding their usual patterns of activity during the previous month. Such behaviors included occupational, locomotive, household, leisure, and exercise activities, as well as sleep and sedentary time.

Results: In men, the total WBC count decreased with increasing levels of exercise energy expenditure, after adjusting for confounders. A similar result was observed for neutrophil counts in both genders. A multivariate logistic regression model showed that exercise energy expenditure had significant negative linear relationships with the elevated WBC and neutrophil counts in men (p = 0.019 and 0.026, respectively). As compared to men who didn't exercise regularly the odds ratios of the elevated total WBC and neutrophil counts decreased significantly in the third tertile by 50 % and 51 %, respectively. However, no similar association was observed in women.

Conclusion: Exercise energy expenditure is inversely and independently associated with the WBC and neutrophil counts among healthy Japanese male workers.