Effects Of Different Exercise Stimuli On Leukocyte Subsets

Abstract

PURPOSE: To determine the impact of acute bouts of different exercises on leukocyte subsets among male collegiate athletes. METHODS: Ten resistance-trained male athletes between 20 - 25 yr of age (22.10 + 1.26 yr) with at least 2 yr resistance training experience (2.66 + 0.64 yr) and a minimum maximal oxygen consumption (VO2max) of 45 mL·kg−1·min−1 (54.41 + 4.15 mL·kg−1·min−1) completed 3 different conditions on separate occasions in a randomized order. On one occasion, subjects performed a bout of resistance exercise (RE) for 27.32 min (+ 0.36). The RE included the back parallel squat and the leg press each at 45% & 55% of 1-RM for first 2 sets, and 65% of 1-RM for the remaining 3 sets. All exercises were performed with a 2:2 cadence followed by 1.5 min rest periods. During the second occasion, subjects performed 30 min of treadmill running (RUN) at 75% VO2max. The third occasion required subjects to serve as their own controls (CON) and remain seated for 2.5 hr. Blood samples were collected at rest, immediately following exercise, and at 2 hr postexercise. RESULTS: Repeated measures ANOVA revealed there was a significant difference between the CON condition and both exercise conditions (p < 0.05). A significant (p < 0.05) total leukocyte difference was detected between the CON (5.65 + 0.33 × 103μL), and RE (8.61 + 0.64 × 103μL) and RUN conditions (8.01 + 0.13 × 103μL). There was a trend for increases (p < 0.05) in total leukocytes, monocytes, & lymphocytes immediately postexercise and a significant (p < 0.05) increase neutrophils at 2 hr postexercise. Lymphocyte numbers declined at 2 hr postexercise to below baseline values in RE (2.65 + 0.55 × 103μL vs. 1.38 + 0.30 × 103μL, p < 0.05). CONCLUSIONS: These data indicate that an acute bout of RE and RUN induced leukocytosis, monocytosis, & lymphocytosis immediately postexercise; however, lymphocytopenia was only observed in RE at 2 hr postexercise. The RUN intensity and duration may have not been enough of a stimulus to impact the immune cells. Support made possible by the Vermont Genetics Network through Grant Number P20 RR16462 from the INBRE Program of the National Center for Research Resources (NCRR), a component of the National Institutes of Health (NIH). Its contents are solely the responsibility of the authors and do not necessarily represent the official views of NCRR or NIH.