The Effect of Environmental Disasters on Endocrine Status, Hematology Parameters, Body Composition, and Physical Performance in Young Soccer Players: A Case Study of the Aral Sea Region

The Aral Sea region (Uzbekistan) is infamous because of the ecological disaster characterized by the disappearance of the Aral Sea due to excessive uncontrolled water intake for agriculture needs. A new desert occurrence, soil and climate aridization led to pesticide and toxic metals environment pollution. The impact of environmental conditions in some areas of Uzbekistan on the health of soccer players is not as noticeable as, for example, the effectiveness of training, so it is not widely discussed in scientific papers. The aim of the present study was to study the features of endocrine status, hematology parameters (e.g., red blood cells (RBC) and hemoglobin (Hb)), and their influence on body composition and physical fitness performance in local young soccer players of the Aral Sea region as the territory of ecological disaster. The study involved 60 male soccer players aged from 18 to 22 years. Participants were divided into two groups: the experimental group (EG), which consisted of 30 soccer players living on the territory of the Aral ecological disaster region, and the control group (CG), which included 30 soccer players, natives of the ecologically favorable region of Uzbekistan. All volunteers had anthropometric measurements, concentrations of insulin-like growth factor-1 (IGF-1), total testosterone (TT), estradiol (E2), cortisol (C), RBC, and Hb count. Moreover, Yo-Yo Intermittent Recovery Test Level 1 (YYIRT1) and professional skills tests such as dribbling shuttle test (DSt) and goal accuracy test (GAt) were assessed. When comparing the CG group to the EG group, it was observed that the EG group exhibited statistically significantly reduced levels of TT and E2 (p < 0.05). No significant statistical difference was observed between the two groups in terms of IGF-1 and C (p > 0.05). Regarding hematological parameters, Hb, Ht, and mean corpuscular volume (MCV) were found to be significantly lower in the EG compared with the CG (p < 0.05). Moreover, the distance covered in the YYIR1 test was found to be significantly lower in soccer players within the EG compared with the CG (p < 0.05). Additionally, it was determined that there was no significant difference between the groups in terms of DSt and GAt values (p > 0.05). Lastly, significant differences were observed between the EG and CG in terms of anthropometric characteristics (diameters, skinfold, and somatotype profile) (p < 0.05). The present study showed that the changes in evaluated characteristics might result from the complex influence of endocrine-disrupting chemicals, the content of which is high in the environment of the Aral Sea region. The results obtained may help monitor the health of athletes living in an environmentally unfriendly environment.

[The structural component of the vascular adrenoreactivity of the skeletal muscles in normo- and hypertensive rats]

In anesthetized normotensive (WKY) and spontaneously hypertensive (SHR) rats the adrenoreactivity in the maximum dilated vessels of hind leg skeletal muscles was compared. Adrenoreactivity mentioned above has been registered as an amplitude of changes of hydraulic resistance (R), hydrostatic capillary pressure (Pc) and capillary filtration coefficient (CFC) to noradrenaline infusion in the vascular bed of perfused skeletal muscles. Resistance changes were more considerable in experiments on the SHR comparatively to those in the WKY. Changes of CFC as well as Pc in both strains were not statistically differed. The data obtained confirm Folkow's hypothesis about increased adrenoreactivity of the resistance vessels in hypertensive mammals due to structural changes of the vascular bed.

[The role of the endothelium in the local vascular reactions of the skeletal muscles]

Chemical de-endothelialization of the m. gastrocnemius' vessels nearly completely blocked the working, reactive and postelongation hyperemia as well as the hyperemia induced with augmentation of the amplitude of intra-vessel pressure pulses. Endothelium seems to take part in the above responses through effects upon the vessels' smooth muscles of a vasodilatory substance released or synthesized by the endothelial cells in the mechanical deformation.

[A comparative evaluation of the hemodynamic parameters and of the vascular adrenergic reactions in the skeletal muscles of normo- and hypertensive rats]

In normotensive and hypertonic rats of the WKY and SHR lines, resp., a significant difference between values of the resistance against blood flow was found: it was 1.34 and 1.5-fold greater in the latters for the regimens of constant perfusion pressure and stabilised blood flow, resp. The capillary hydrostatic pressure and the capillary filtration coefficient did not differ significantly in both groups. The increase of the vascular resistance in skeletal muscles in response to noradrenaline administration was significantly lesser in the hypertensive rats. The data obtained suggest that the extent of distensibility of the vascular bed by the blood pressure can be a determining factor of the adrenergic shift of vascular resistance in both groups of animals.

[The superposition of neural vasoconstrictor and local vasodilator effects on skeletal muscle vessels]

In anesthetised cats' m. gastrocnemius, under conditions of stabilised perfusion pressure, preservation of the sympathetic effect against the background of reactive and working hyperemia was shown in both rhythmic muscle contractions and in single tetani. The reactive hyperemia practically did not develop during sympathetic stimulation whereas the working one turned out to be a short-term one and considerably weakened as compared with the control.

[Role of compression of the vessels of the gastrocnemius muscle in changes in its blood supply during stretching]

In the m. gastrocnemius of anesthetized cats, the pressure of tissue resistance balancing was 5 mm Hg initially and developed a 7-fold increase in longitudinal stretch of the muscle by 10-20% when the total mechanical tension increased 20-fold (from 2400 to 47 662 H/m2) and the blood flow reduced from 5.0 to 3.0 ml . min-1 (100 r)-1. Decrease of the blood flow in stretching and the postelongation hyperemia could not be reproduced in external compression of the muscle equal to the balancing pressure at a given stretching. Only the external pressure 50 and 100 mm Hg decelerated the blood flow and developed a hyperemia even though a lesser one than the postelongation hyperemia. The effect of longitudinal muscle stretch on its vessels is not limited by their compression with the "intramuscular pressure".

[Effect of stretching of the cat gastrocnemius muscle on its tetany, postcontraction hyperemia and energy metabolism indices]

Longitudinal stretch of the muscle in the range E = 0.11-0.17 (111-117% of the initial length) is followed by increase in passive strength and in mechanical displays of the 15-sec isometric Blood flow in the muscle vessels decreases at rest in the longitudinal stretching whereas O2 extraction from the blood increases; O2 consumption and ration of arterio-venous differences in the lactate and pyruvate concentration do not change. Additional posttetanic blood supply in the muscle, posttetanic alteration of the O2 consumption in it and the lactate/pyruvate ratio in longitudinal stretch do not differ from the analogous parameters in the initial--length muscle. The data obtained are in accordance with the metabolic theory of the hyperemia mechanisms but can hardly be explained from the standpoint of the histomechanical theory.

[Changes in blood flow after longitudinal stretching of the cat m. gastrocnemius]

Longitudinal stretch of the cat m. gastrocnemius by 10-30% of initial length increased the passive strength and regularly decreased the blood flow, the latter being dependent not on the degree of deformation but on the value of passive tension. Postelongation hyperemia develops after the stretch. This reaction seems to be similar to hyperemia due to the artery occlusion in the muscle and is considerably weaker than the postcontraction increase in the blood flow. The character of intramuscular mechanical effects on the vessels during both the active contractions and the passive stretch, is discussed.