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 <front>
  <journal-meta>
   <journal-id journal-id-type="publisher-id">Russian Journal of Information Technology in Sports</journal-id>
   <journal-title-group>
    <journal-title xml:lang="en">Russian Journal of Information Technology in Sports</journal-title>
    <trans-title-group xml:lang="ru">
     <trans-title>Российский журнал информационных технологий в спорте</trans-title>
    </trans-title-group>
   </journal-title-group>
   <issn publication-format="online">2949-6349</issn>
  </journal-meta>
  <article-meta>
   <article-id pub-id-type="publisher-id">84842</article-id>
   <article-id pub-id-type="doi">10.62105/2949-6349-2024-1-2-13-27</article-id>
   <article-id pub-id-type="edn">yylwsc</article-id>
   <article-categories>
    <subj-group subj-group-type="toc-heading" xml:lang="ru">
     <subject>ЦИФРОВЫЕ ТЕХНОЛОГИИ В ЭКСТРЕМАЛЬНОЙ И СПОРТИВНОЙ ФИЗИОЛОГИИ</subject>
    </subj-group>
    <subj-group subj-group-type="toc-heading" xml:lang="en">
     <subject>DIGITAL TECHNOLOGIES IN EXTREME AND SPORTS PHYSIOLOGY</subject>
    </subj-group>
    <subj-group>
     <subject>ЦИФРОВЫЕ ТЕХНОЛОГИИ В ЭКСТРЕМАЛЬНОЙ И СПОРТИВНОЙ ФИЗИОЛОГИИ</subject>
    </subj-group>
   </article-categories>
   <title-group>
    <article-title xml:lang="en">An algorithm for quantifying cardiorespiratory synchronization to assess the functional state and intersystems interactions in athletes</article-title>
    <trans-title-group xml:lang="ru">
     <trans-title>Алгоритм количественной оценки кардиореспираторной синхронизации для характеристики функционального состояния и межсистемных взаимодействий у спортсменов</trans-title>
    </trans-title-group>
   </title-group>
   <contrib-group content-type="authors">
    <contrib contrib-type="author">
     <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-7377-3408</contrib-id>
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Ковалева</surname>
       <given-names>Анастасия Владимировна</given-names>
      </name>
      <name xml:lang="en">
       <surname>Kovaleva</surname>
       <given-names>Anastasia Vladimirovna</given-names>
      </name>
     </name-alternatives>
     <email>kovaleva_av@academpharm.ru</email>
     <bio xml:lang="ru">
      <p>кандидат биологических наук;</p>
     </bio>
     <bio xml:lang="en">
      <p>candidate of sciences in biology;</p>
     </bio>
     <xref ref-type="aff" rid="aff-1"/>
     <xref ref-type="aff" rid="aff-2"/>
    </contrib>
    <contrib contrib-type="author">
     <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-1111-8576</contrib-id>
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Анисимов</surname>
       <given-names>Виктор Николаевич</given-names>
      </name>
      <name xml:lang="en">
       <surname>Anisimov</surname>
       <given-names>Viktor Nikolaevich</given-names>
      </name>
     </name-alternatives>
     <email>victor_anisimov@neurobiology.ru</email>
     <bio xml:lang="ru">
      <p>кандидат биологических наук;</p>
     </bio>
     <bio xml:lang="en">
      <p>candidate of sciences in biology;</p>
     </bio>
     <xref ref-type="aff" rid="aff-3"/>
    </contrib>
   </contrib-group>
   <aff-alternatives id="aff-1">
    <aff>
     <institution xml:lang="ru">Федеральное государственное бюджетное научное учреждение&quot;Федеральный исследовательский центр оригинальных и перспективных биомедицинских и фармацевтических технологий» (НИИ Нормальной физиологии им. П.К. Анохина)</institution>
     <city>Москва</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Federal Research Center for Innovator and Emerging Biomedical and Pharmaceutical Technologies</institution>
     <city>Moscow</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-2">
    <aff>
     <institution xml:lang="ru">Государственное казенное учреждение &quot;Центр спортивных инновационных технологий и подготовки сборных команд&quot; Москомспорта</institution>
     <city>Москва</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Moscow Center of Advanced Sports Technologies</institution>
     <city>Moscow</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-3">
    <aff>
     <institution xml:lang="ru">МГУ им. М.В. Ломоносова</institution>
     <city>Москва</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Lomonosov Moscow State University</institution>
     <city>Moscow</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <pub-date publication-format="print" date-type="pub" iso-8601-date="2024-10-11T00:00:00+03:00">
    <day>11</day>
    <month>10</month>
    <year>2024</year>
   </pub-date>
   <pub-date publication-format="electronic" date-type="pub" iso-8601-date="2024-10-11T00:00:00+03:00">
    <day>11</day>
    <month>10</month>
    <year>2024</year>
   </pub-date>
   <volume>1</volume>
   <issue>2</issue>
   <fpage>13</fpage>
   <lpage>27</lpage>
   <history>
    <date date-type="received" iso-8601-date="2024-07-01T00:00:00+03:00">
     <day>01</day>
     <month>07</month>
     <year>2024</year>
    </date>
    <date date-type="accepted" iso-8601-date="2024-07-25T00:00:00+03:00">
     <day>25</day>
     <month>07</month>
     <year>2024</year>
    </date>
   </history>
   <self-uri xlink:href="https://rjits.ru/en/nauka/article/84842/view">https://rjits.ru/en/nauka/article/84842/view</self-uri>
   <abstract xml:lang="ru">
    <p>Введение. Ритм сердца тесно связан с ритмом дыхания. Хорошо известно явление дыхательной синусовой аритмии: увеличение частоты сердечных сокращений при вдохе и уменьшение при выдохе. Кардиореспираторные взаимодействия и синхронизация этих двух сигналов оценивается в литературе по-разному. Целью данной работы было предложить и апробировать подход к оценке кардиореспираторной синхронизации, который позволяет более объективно охарактеризовать это состояние, – расчет коэффициента кросс-корреляции между частотой сердечных сокращений и кривыми дыхания. &#13;
Методы. У 45 здоровых спортсменов (18-25 лет) регистрировали фотоплетизмограмму и дыхание в трех ситуациях: функциональный покой, ритмизированное дыхание на частоте 6 раз в минуту (резонансная частота) и выполнение сенсомоторного задания (теппинг ладонью под ритмически звуки метронома и затем воспроизведение заданного ритма по памяти). В отношении кривых изменения ЧСС и дыхания применяли последовательно алгоритмы фильтрации и сглаживания по методу Савицкого-Голея, а затем вычисление коэффициента кросс-корреляции между двумя кривыми. Также были получены классические показатели спектрального анализа вариабельности ритма сердца (LF и HF), так как при спонтанном дыхании его вклад в ритм сердца отражается в волнах HF, а при дыхании на резонансной частоте возникает пик на частоте 0.1 Гц в LF диапазоне.&#13;
Результаты. Коэффициент кросс-корреляции, как и мощность пика на частоте 0.1 Гц в спектре ритма сердца, значительно растут при дыхании на резонансной частоте. При этом наиболее точно взаимосвязь между этими показателями описывается не линейной, а логарифмической зависимостью. При выполнении сенсомоторного задания так-называемые дыхательные волны в спектре ритма сердца (HF) не меняются от состояния покоя к теппингу по метроном и затем к удержанию ритма по памяти. При этом коэффициент кросс-корреляции демонстрирует значимые изменения методу этими ситуациями. Кроме того, была выявлена корреляционная связь между изменением коэффициента кросс-корреляции и устойчивостью удержания ритма по памяти: усиление кардиореспираторной синхронизации приводит к снижению устойчивости.&#13;
Заключение. Оценка кардиореспираторной синхронизации в связи с особенностями обоих сигналов (изменения ЧСС и фаз дыхания) требует предварительной подготовки массивов данных: фильтрации и сглаживания ступенчатой кривой изменения ЧСС. Вычисление коэффициента кросс-корреляции может быть использовано для оценки кардиореспираторной синхронизации в режиме реального времени и, вероятно, будет применимо коротких временных фрагментах для оценки эмоциональных реакций и при других быстрых колебаниях психофизиологических состояний, где классические метод анализа изменения ритма сердца (спектральный, временно́й) применять не всегда корректно.</p>
   </abstract>
   <trans-abstract xml:lang="en">
    <p>Introduction. The rhythm of the heart (heart rate, HR) is closely related to the rhythm of breathing. The phenomenon of respiratory sinus arrhythmia (an increase in heart rate during inhalation and a decrease during exhalation) is well known. Cardiorespiratory interactions and synchronization of these two signals are evaluated differently in the literature. The purpose of this work was to propose and test an approach to assess cardiorespiratory synchronization – the calculation of the cross-correlation coefficient between heart rate and respiration curve, for a more objective characterization of an athlete’s bodily states. &#13;
Methods. A photoplethysmogram and respiration were recorded in 45 healthy athletes (18-25 years old) in three situations: rest, paced breathing at 6 times per minute (resonant frequency) and the performance of a sensorimotor task (tapping with the rhythmic metronome sounds and then reproducing a given rhythm from memory). For the HR and respiration curves, filtering and smoothing algorithms using the Savitsky-Goley method were applied sequentially, and then the cross-correlation coefficient between the two curves was calculated. The spectral parameters of heart rate variability (LF and HF) were also obtained, since during spontaneous breathing its contribution to the HR is reflected in HF band, and when breathing at a resonant frequency, a peak occurs at a frequency of 0.1 Hz in the LF band.&#13;
Results. The cross-correlation coefficient, as well as the peak of HR spectral power at 0.1 Hz, increases significantly when breathing at a resonant frequency. The relationship between these indicators is most accurately described not by a linear, but by a logarithmic dependence. When performing a sensorimotor task, the so-called respiratory waves in the heart rhythm spectrum (HF) do not change from rest to tapping by a metronome and then to holding the rhythm by memory. At the same time, the cross-correlation coefficient demonstrates significant changes between these situations. In addition, a significant correlation was found between the change in the cross-correlation coefficient and the stability of rhythm maintenance (from memory): an increase in the cardiorespiratory synchronization leads to a decrease in motor rhythm stability.&#13;
Conclusion. Assessment of cardiorespiratory synchronization due to the peculiarities of both signals (changes in heart rate and respiratory phases) requires preliminary preparation of data arrays: filtering and smoothing the stepped curve of heart rate dynamics. The calculation of the cross-correlation coefficient can be used to assess cardiorespiratory synchronization in real time and is likely to be applicable in short time fragments to assess emotional reactions and other short-term fluctuations in psychophysiological conditions, where the classical method of assessing changes in heart rhythm in the frequency or time domains is not applicable.</p>
   </trans-abstract>
   <kwd-group xml:lang="ru">
    <kwd>кардиореспираторная синхронизация</kwd>
    <kwd>частота сердечных сокращений</kwd>
    <kwd>дыхательная синусовая аритмия</kwd>
    <kwd>вариабельность ритма сердца</kwd>
    <kwd>резонансное дыхание</kwd>
    <kwd>спектральный анализ</kwd>
    <kwd>эмоциональные реакции</kwd>
    <kwd>психофизиологические состояния</kwd>
   </kwd-group>
   <kwd-group xml:lang="en">
    <kwd>cardiorespiratory synchronization</kwd>
    <kwd>heart rate</kwd>
    <kwd>respiratory sinus arrhythmia</kwd>
    <kwd>heart rate variability</kwd>
    <kwd>resonant breathing</kwd>
    <kwd>spectral analysis</kwd>
    <kwd>emotional reactions</kwd>
    <kwd>psychophysiological conditions</kwd>
   </kwd-group>
  </article-meta>
 </front>
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