Effects of laboratory versus field exercise on leukocyte subsets and cell adhesion molecule expression in children

Abstract

In adults, exercise is a powerful and natural stimulator of immune cells and adhesion molecules. Far less is known about these exercise responses during childhood and whether or not exercise in real-life activities of healthy children might in¯uence immune responses. We compared laboratory exercise (10´2 min periods of heavy, constant intensity, cycle ergometer exercise with 1 min rests between exercise in nine subjects, aged 9±15 years) with ®eld exercise (90 min soccer practice in nine di erent subjects, aged 9±11 years). Blood was sampled before both protocols, 5 min after the 30 min laboratory protocol, and 10±15 min after the 90 min ®eld protocol. Both ®eld and laboratory exercise protocols led to signi®cant (P<0.05) increases in granulocytes, monocytes, and all lymphocyte subpopulations. The mean (SEM) increases were similar for the two protocols except for the signi®cantly greater increase in laboratory compared with ®eld protocols for natural killer cells [142 (39)% vs 12 (16) (25)%] protocol. Finally, the density of CD62L on lymphocytes signi®cantly decreased with laboratory exercise but showed no change in the ®eld protocol [±20 (3)% vs ±3 (3)%, P<0.001]. The rapid and substantial immune response in both laboratory and ®eld protocols suggests that exercise stimulation of the immune system occurs commonly in the real lives of children and may play a role in their overall immune status.

Patients with solid tumors treated with high-temperature whole body hyperthermia show a redistribution of naive/memory T-cell subtypes

“…Again, none of these findings were observed in the group of healthy volunteers performing physical exercise. Exhaustive physical exercise has been shown to be capable of elevating peripheral numbers of T-helper cells (13,14,24,30,33). In our healthy subjects performing moderate physical exercise, however, we did not observe any significant changes in the number of CD4 ϩ T cells during the course of the experiment.…”

“…hGH, also known as somatotropin, is mainly produced in the anterior pituitary, but it has been shown to be secreted by lymphocytes and macrophages, as well (46,48). Plasma concentrations of hGH increase in response to strenuous exercise, but this increase seems to depend on the exercise-related rise in body core temperature (5,18,30).…”

“…Furthermore, WBH causes an increase in serum levels of sIL-2R, a marker for T-cell activation in humans (2). Both, WBH and exhaustive physical exercise are known to influence the cellular immune system, especially on numbers of peripheral NK and T cells (2,8,13,14,24,30,33). To learn more about the effects of both procedures on the T-cell-mediated immune response, it seemed interesting to analyze whether WBH or physical stress would differently affect naive, central-memory, and effector T cells.…”

“…Accordingly, it has previously been shown that a combination of exercise and that heat stress augments both hormonal and immune responses. These changes, however, seemed to be reversed if temperatures are clamped by exercising in cold water (5,30,32,33), suggesting that an exercise-induced threshold of ϳ38°C body core temperature exists where hormonal and immunological consequences of exercise can be observed (32).…”

The Effect of Brief Exercise on Circulating CD34+ Stem Cells in Early and Late Pubertal Boys

“…t is now well established that brief bouts of exercise in healthy children and adolescents substantially increase the number of circulating neutrophils, monocytes, and lymphocytes and their subpopulations (1). In addition, exercise is associated with increases of inflammatory mediators such as IL-6, IL-1␤, TNF-␣ and IL-1 receptor antagonist (IL-1ra) (2).…”