Skip Navigation LinksHome > May 2006 - Volume 38 - Issue 5 > Puberty Effects on NK Cell Responses to Exercise and Carbohy...
Medicine & Science in Sports & Exercise:
doi: 10.1249/01.mss.0000218124.87917.40
BASIC SCIENCES: Original Investigations

Puberty Effects on NK Cell Responses to Exercise and Carbohydrate Intake in Boys

TIMMONS, BRIAN W.1; TARNOPOLSKY, MARK A.2; SNIDER, DENIS P.3; BAR-OR, ODED1

Collapse Box

Abstract

Previous research has demonstrated that younger versus older animals and humans experience smaller perturbations in natural killer (NK) cells in response to physiological stress.

Purpose: To determine whether the smaller perturbations in NK cells induced by strenuous exercise and carbohydrate (CHO) intake, previously reported in children, are influenced by puberty.

Methods: Twenty 12-yr-old boys, distinguished as prepubertal (Tanner (T) 1, N = 7), early pubertal (T2, N = 7), or pubertal (T3-5, N = 6), cycled for 60 min at 70% V̇O2max while drinking 6% CHO (CT) or flavored water (WT). Blood was collected at rest and during (30 and 60 min) and following (30 and 60 min) exercise to identify NK cells as CD3CD56dim or CD3CD56bright. CD69 expression on CD3CD56+ cells was also determined.

Results: A puberty × CHO × exercise interaction was found for the proportion, but not number, of CD56dim cells (P = 0.06). CD56dim cell counts were lower in CT versus WT (P < 0.001). Responses of CD56bright proportions (P = 0.007) and counts (P = 0.03) depended on pubertal status, but not CHO. The CD56bright:CD56dim ratio remained stable during exercise, but during recovery was higher in T1 and T3-5 versus T2 (P = 0.08) and in CT versus WT (P = 0.04). During recovery, CD3CD56+ cells expressed higher levels of CD69 (P = 0.01), with no change in the proportion of CD69+ cells.

Conclusion: These results confirm the influence of puberty on the distribution of NK cell subsets in response to exercise and CHO intake. Increased CD69 expression suggests that NK cells increase activation status during recovery from physiological stress.

©2006The American College of Sports Medicine

Login

Article Tools

Share

Search for Similar Articles
You may search for similar articles that contain these same keywords or you may modify the keyword list to augment your search.

Connect With Us