Leukocytosis Occurs in Response to Resistance Exercise in Men
Leukocytosis Occurs in Response to Resistance Exercise in Men
The Journal of Strength and Conditioning Research: Vol. 18, No. 2, pp. 266271.
Shawn R. Simonson
School of Kinesiology and Physical Education, University of Northern Colorado, Greeley, Colorado 80639; Department of Wellness and Movement Sciences, Western New Mexico University, Silver City, New Mexico 88062
Catherine G.R. Jackson
School of Kinesiology and Physical Education, University of Northern Colorado, Greeley, Colorado 80639; Department of Wellness and Movement Sciences, Western New Mexico University, Silver City, New Mexico 88062; Department of Kinesiology, California State University-Fresno, Fresno, California 93740
ABSTRACT
Simonson, S.R., and C.G.R. Jackson. Leukocytosis occurs in response to resistance exercise in men. J. Strength Cond. Res. 18(2):266271. 2004.The purpose of this study was to determine the effects of a single bout of resistance exercise on immune cell numbers of moderately active men. Subjects were 16 male volunteers (mean ± standard deviation [SD] age 30 ± 7 years, height 180.1 ± 7.0 cm, mass 83.97 ± 10.33 kg); 8 were randomly assigned to treatment and 8 to control groups. Treatment was a common resistance training routine (3 sets of 810 repetitions at 75% of 1 repetition maximum) of 8 large muscle mass exercises using resistance machines. Blood samples were drawn before exercise and at 0 minutes (P0), 15 minutes (P15), and 30 minutes (P30) postexercise. Control subjects sat quietly in the training facility; blood was drawn at the same intervals as treatment. Leukocyte and lymphocyte (LY) subpopulation numbers were determined. Statistical analysis was analysis of variance (ANOVA) (repeated measures, p 0.050) and multiple comparisons (Dunn method) to isolate variability. All leukocyte subpopulations, except basophils (BA) and eosinophils (EO), increased and counts declined by P15 and P30. Only neutrophils (NE) did not return to preexercise levels by P30. The majority of resistance exercise induced leukocytosis was due to an increase in circulating LY (natural killer cells increased most, CD4+/CD8+ ratio unchanged) and monocytes (MO). The transient, inconsequential immune cell population responses to resistance exercise are similar to those during aerobic activity. The lack of large alterations in and rapid recovery from cell number changes suggests that resistance exercise is not immunosuppressive.
