Sports Tourism, Sports Physiology and Medicine

During the last two decadesnumerous research teams demonstratedthat skeletalmuscles
function as an exercise-dependent endocrine organ secreting dozens of myokines. Variety of
physiological and pathophysiological implications of skeletalmusclemyokines secretion has been
described; however, upstream signals and sensing mechanisms underlying this phenomenon
remain poorly understood. It is well documented that in skeletal muscles intensive exercise triggers
dissipation of transmembrane gradient of monovalent cations caused by permanent activation
of voltage-gated Naþ and Kþ channels. Recently, we demonstrated that sustained elevation
of the [Naþ]i/[Kþ]i ratio triggers expression of dozens ubiquitous genes including several canonical
myokines, such as interleukin-6 and cyclooxygenase 2, in the presence of intra- and extracellular
Ca2þ chelators. These data allowed us to suggest a novel [Naþ]i/[Kþ]i-sensitive, Ca2þ
i -independent
mechanism of excitation-transcription coupling which triggers myokine production. This pathway
exists in parallel with canonical signaling mediated by Ca2þ
i , AMP-activated protein kinase and
hypoxia-inducible factor 1a (HIF-1a). In ourmini-reviewwe briefly summarize data supporting this
hypothesis as well as unresolved issues aiming to forthcoming studies.

Recently we found that cytoplasm of permeabilized mammalian cells behaves as a hydrogel displaying intrinsic
osmosensitivity. This study examined the role of microfilaments and microtubules in the regulation of hydrogel
osmosensitivity, volume-sensitive ion transporters, and their contribution to volume modulation of intact cells.
We found that intact and digitonin-permeabilized A549 cells displayed similar rate of shrinkage triggered by
hyperosmotic medium. It was significantly slowed-down in both cell preparations after disruption of actin
microfilaments by cytochalasin B, suggesting that rapid water release by intact cytoplasmic hydrogel contributes
to hyperosmotic shrinkage. In hyposmotic swelling experiments, disruption of microtubules by vinblastine attenuated
the maximal amplitude of swelling in intact cells and completely abolished it in permeabilized cells. The
swelling of intact cells also triggered ~10-fold elevation of furosemide-resistant 86Rb+ (K+) permeability and
the regulatory volume decrease (RVD), both ofwhich were abolished by Ba2+. Interestingly, RVD and K+ permeability
remained unaffected in cytocholasin/vinblastine treated cells demonstrating that cytoskeleton disruption
has no direct impact on Ba2+-sensitive K+-channels involved in RVD. Our results show, for the first time, that the
cytoskeleton network contributes directly to passive cell volume adjustments in anisosmotic media via the
modulation of the water retained by the cytoplasmic hydrogel.

Physiological and biomechanical characteristics of the kick and goal technique in football were studied in athletes of different qualification. The formation of technological skills of football players kicking the ball from the standard position requires coordinated movements and high differentiation of muscular activity.

This review summarizes the data on the functioning of carriers providing electroneutral symport of sodium,
potassium, and chloride (Na+,K+,2Cl– cotransport), potassium and chloride (K+,Cl– cotransport), and sodium and chloride
(K+,Cl– cotransport) as well as molecular mechanisms of the regulation of these carriers and their physiological significance.
We emphasized the involvement of chloridecoupled carriers in the regulation of cell volume and intracellular chloride concentration and novel data on the role of ubiquitous isoform of Na+,K+,2Cl– cotransporter NKCC1 in regulation of vascular
smooth muscle contraction and activity of GABAA receptors. Finally, we analyzed the data on activation of NKCC1 in
patients with essential hypertension and its role in the longterm maintenance of elevated systemic blood pressure and myogenic response in microcirculatory beds.

A drop in oxygen partial pressure results in elevation of blood vessel diameter. It has been demon
strated that isolated vessels exhibit this unique feature only when they are perfused in the presence of eryth
rocytes. More recently, it was shown that haemoglobin plays a key role in oxygen sensing. Its deoxygenated
form interacts with band 3 protein, triggering the cascade of nonidentified intracellular signals involved in
nitric oxide production and release of ATP interacting with P2Y purinergic receptors in endothelial cells. In
this review, we summarize the data on mechanisms of ATP release from erythrocytes, as well as on its phys
iological and pathophysiological implications.

This study examines the relative impact of canonical hypoxia-inducible factor-1alpha- (HIF-1a and Na+
i/K+
i-mediated
signaling on transcriptomic changes evoked by hypoxia and glucose deprivation. Incubation of RASMC in ischemic
conditions resulted in ,3-fold elevation of [Na+]i and 2-fold reduction of [K+]i. Using global gene expression profiling we
found that Na+,K+-ATPase inhibition by ouabain or K+-free medium in rat aortic vascular smooth muscle cells (RASMC) led to
the differential expression of dozens of genes whose altered expression was previously detected in cells subjected to
hypoxia and ischemia/reperfusion. For further investigations, we selected Cyp1a1, Fos, Atf3, Klf10, Ptgs2, Nr4a1, Per2 and
Hes1, i.e. genes possessing the highest increments of expression under sustained Na+,K+-ATPase inhibition and whose
implication in the pathogenesis of hypoxia was proved in previous studies. In ouabain-treated RASMC, low-Na+, high-K+
medium abolished amplification of the [Na+]i/[K+]i ratio as well as the increased expression of all tested genes. In cells
subjected to hypoxia and glucose deprivation, dissipation of the transmembrane gradient of Na+ and K+ completely
eliminated increment of Fos, Atf3, Ptgs2 and Per2 mRNAs and sharply diminished augmentation expression of Klf10, Edn1,
Nr4a1 and Hes1. In contrast to low-Na+, high-K+ medium, RASMC transfection with Hif-1a siRNA attenuated increments of
Vegfa, Edn1, Klf10 and Nr4a1 mRNAs triggered by hypoxia but did not impact Fos, Atf3, Ptgs2 and Per2 expression. Thus, our
investigation demonstrates, for the first time, that Na+
i/K+
i-mediated, Hif-1a- -independent excitation-transcription coupling
contributes to transcriptomic changes evoked in RASMC by hypoxia and glucose deprivation.

Age and genderrelated and individual characteristics of hypoxic resistance in healthy subjects
with different temperaments (choleric and sanguine persons) were studied, and different responses to acute
normobaric hypoxia (inhalation of air with 10% O2) were found. The agerelated changes in the dynamics of
blood oxygen saturation after the acute hypoxia were manifested at the level of certain sections on the SpO2
curve (phases of delay, decline, and rise). It is established that, in children, the sensitivity to acute hypoxia was
higher than in teenagers and that in teenagers is was higher than in adults. A higher lability of mental pro
cesses, the predominance of sympathetic activity in the autonomic regulation, and a greater personal anxiety
are associated with the choleric temperament. The choleric persons are characterized by a slower restoration
of blood oxygen saturation to the initial level after acute hypoxia than the sanguine persons, which is regarded
as a lower hypoxic resistance of the former. We have developed a complex algorithm describing the depen
dence of the oxygen saturation dynamics in different phases of the hypoxic test, which can be used as a uni
versal method of the estimation of hypoxic resistance in different groups of the population.

Physiological parameters of hitting the ball in the unsupported position and prospects for improv
ing spikes through training with a biological feedback were studied in volleyball players. The physiological and
biomechanical parameters characterizing a direct attacking shot in a supported position correlate with the
biomechanical specificities characterizing the performance of this short in a jump. At the same time, the
physiological ability to provide the accuracy of hitting actions is associated, first, with improving the coordi
nation of trunk and arm movements in the flight phase, second, with the factors of intramuscular and inter
muscular coordination of the striking arm, and, third, with a change in the pattern of motions of an athlete’s
center of pressure. The use of a computerbased stabilographic method of training with a biofeedback con
tributes to the optimization of physiological and biomechanical parameters of motor actions in the unsup
ported position, which results in an increased accuracy of hitting the ball in a jump. The obtained results open
prospects for applying the method of computerbased stabilography for improving the performance skill of
accuracy and targetoriented actions in unsupported positions in various kinds of sports.

Herewereviewavailabledataonnitricoxide(NO)-mediatedsignalinginskeletalmuscleduringphysicalexercise.Nitricoxidemodulatesskeletalmyocytefunction,hormoneregulation,andlocalmicrocirculation.NitricoxideunderliesthetherapeuticeffectsofphysicalactivitywhereasthepharmacologicalmodulatorsofNO-mediatedsignalingarethepromisingtherapeuticagentsindifferentdiseases.Nitricoxideproductionincreasesinskeletalmuscleinresponsetophysicalactivity.Thismoleculecanalterenergysupplyinskeletalmusclethroughhormonalmodulation.Mitochondriainskeletalmuscletissuearehighlyabundantandplayapivotalroleinmetabolism.ConsideringNOaplausibleregulatorofmitochondrialbiogenesisthatdirectlyaffectscellularrespiration,wediscussthemechanismsofNO-inducedmitochondrialbiogenesisintheskeletalmusclecells.Wealsoreviewavailabledataonmyokines,themoleculesthatareexpressedandreleasedbythemusclefibersandexertautocrine,paracrineand/orendocrineeffects.ThearticlesuggeststhepresenceofputativeinterplaybetweenNO-mediatedsignalingandmyokinesinskeletalmuscle.DatademonstrateanimportantroleofNOinvariousdiseasesandsuggestthatphysicaltrainingmayimprovehealthofpatientswithdiabetes,chronicheartfailure,andevendegenerativemusclediseases.WeconcludethatNO-associatedsignalingrepresentsapromisingtargetforthetreatmentofvariousdiseasesandfortheachievementofbetterathleticperformance.

According to the findings, the common feature of all the examined systems of
motor skill formation is that they solve the problem of creating a specialized environment, which includes
objects of interaction with a person or equivalent models. These actions are designed to construct a safeto-
use environment controlled well by technical means. The educational effect of this technologically rich
environment is provided by the organization of feedback needed to perform the sensory correction of
athlete’s movements. The possibility of control depends on the ability of a trainer to set an algorithm of
actions for an athlete and monitor the characteristics of his motor activity. The technical effect in this case
is represented by changes in the environment and is estimated by the typical change in the indicators of
motion sensors, fixed on the working objects or parts of the human body. Mechanical devices, optical
tracking systems, electromagnetic tracking systems and inertial systems are used as motion detectors.
One of the main conditions for creating a workspace is ensuring autonomic control, intended not
only for decreasing the degree of involvement in training of qualified personnel, but also for reducing the
response time of the elements of the training environment to athlete’s actions, which is crucial in the case
of motor skills.
It is also possible to use new techniques to arrange the developing environment and implement
feedback. First of all it refers to the organization of team work and methodical support, based on the use
of the results of psychological, psycho-physiological and pedagogical research in the field of formation of
motor skills. Here the main drawback of the earlier systems should be eliminated, which is in the fact that
for assessment and self-assessment of athlete’s motor activity the authors almost invariably use the
obvious, but theoretically wrong approach, based on the work with the visualization of the path of
movement, which the student should mechanically reproduce, striving for the standard set by a more
skilled athlete.

The obtained results reveal a number of essential physiological laws that underlie adaptation
of the vegetative-vascular system of the body of women to the conditions of pregnancy and the impact of
physical activity and breathing exercises on this process.