Background: The aim of this study was to determine the relationship between T lymphocytes (CD4⁺, CD8⁺), NK (CD56⁺), CD4⁺/CD8⁺ ratio and maximal oxygen pulse among the active girls in response to an intense aerobic physical activity.

Materials and Methods: This semi-experimental study was conducted on 20-25 years old active women. To estimate maximal oxygen pulse and immune response parameters, GXT treadmill test was performed. In order to evaluate the immune system response to intense physical activity, blood samples were obtained at 3 times (before, immediately after and 2 hours after the exercise).

Results: The T-CD4⁺cells and CD4⁺/CD8⁺ rations were significantly decreased after an intense aerobic physical activity (P<0.05). However, the levels of CD8⁺ and CD56⁺ cells were significantly increased after the same physical activity. The results also showed a significant positive relationship between maximal oxygen pulse and CD8⁺,  CD56⁺ cells level (r=0.699, P<0.001), (r=0.49, P≤0.009). In addition, there was a significant negative relationship between maximal oxygen pulse and CD4⁺ (r=-0.645, P≤0.008), CD4⁺/CD8⁺ T-cell ratios (r= - 0.539, P<0.002).

Conclusion: The findings of this research showed that in active women the maximal oxygen pulse, as an indicator of the efficiency of the cardiovascular system, has strong relationship with some immune system parameters.

Background: Exercise plays an important role in improving cardiovascular function. Due to the increasing tendency of children to the soccer the purpose of this investigation was to examine the effects of a 12 week plyometric and soccer training on the cardiac structure and function of healthy 13-15 years old boys.  

Materials and Methods: This quasi- experimental study was conducted with a pre-test and post-test design. The participants (n=20) were selected among the non-athletic healthy boys (13-15 years) from Miyaneh (East Azerbaijan, Iran). After taking informed consent the participants were voluntarily participated in two equal Training and Control groups. The participants in the Exercise group performed a 12 week plyometric and soccer training. Under basic conditions and after a 12 week follow-up using the echocardiography both groups were examined for left ventricular end-diastolic dimension (LVEDD), left ventricular end-systolic dimension (LVESD), left ventricular end diastolic posterior wall dimension­ (LVPWd), inter-ventricular septal end diastolic dimension (IVSd), stroke volume (SV), ejection fraction (EF) and cardiac output (CO).

Results: After a 12 week training program the LVEDD, LVPWd and SV were significantly increased (P<0.05).  The EF in the Exercise group had no increase. Moreover, LVESD and IVSd were similar in both groups. 

Conclusion: A twelve week plyometric and soccer training in 13-15 years old boys result in significant changes in some cardiac structural and functional indexes.