EFFECT OF AEROBIC TRAINING EXERCISE ON NATURAL KILLER CELLS BEFORE AND AFTER PUBERTY IN GIRLS

Abstract

Background: Effect of exercise on the immune system becomes a very interesting area for research especially in children and period of puberty. Purpose: This study was conducted to investigate the effect of aerobic training exercise on Natural Killer (NK) cells before and after puberty in girls. Subjects: sixty healthy girls aged from 10-15 years divided into two equal groups. The mean age (11.0 ±0.59) for group A (pre-pubertal) and (14.5 ±0.78) for group B (post pubertal). Material: Both groups received aerobic training exercises by walking on treadmill with moderate intensity 60-75% of the maximum heart rate 3 sessions per week for 4 weeks. Blood samples were drawn from both groups before beginning the training and after 24 hours of completing last session to measure NK percentage by measuring its 3phenotypes: CD3", CD16+, CD56 + . Results: There was significant difference between before and after exercise in both groups in CD16+ and the dual( CD16+ + CD56 + )(P=O.OOO) and between before and after exercise in measuring CD56+ in group A, in CD56+ not significant difference between before and after exercise in group B(P=O.ll0) between two groups there was significant difference in pre training level of CD56+ (P=0.02)and in post-training level of CD16+ and the dual CD16+ + CD56 + (P=O.OOO), there was no significant difference in post-training level of CD56+ (P=l.OOO)and also in pre-training level of CD16+ (p=0.266). Conclusion: The aerobic training exercise had a potent effect on NK cells percentage in healthy girls before and after puberty and the effect was clear on NK cells phenotypes: CD16+ and CD56 + and was greater in group A (pre-pubertal) than group B (post-pubertal). Exercise training can substitute the suppressive effect of estrogen on NK cells. So it was recommended with training of girls in pre& post puberty age and especially for pre-puberty girls.