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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">mes</journal-id><journal-title-group><journal-title xml:lang="ru">Экстремальная биомедицина</journal-title><trans-title-group xml:lang="en"><trans-title>Extreme Medicine</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">3033-8964</issn><issn pub-type="epub">3033-8972</issn><publisher><publisher-name>Centre for Strategic Planning of the Federal Medical and Biological Agency</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.47183/mes.2026-526</article-id><article-id custom-type="elpub" pub-id-type="custom">mes-526</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>АВИАКОСМИЧЕСКАЯ И МОРСКАЯ МЕДИЦИНА</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>AEROSPACE &amp; MARITIME MEDICINE</subject></subj-group></article-categories><title-group><article-title>Вегетативная регуляция сердечно-сосудистой системы после пробуждения и двигательная активность во время ночного сна в условиях длительной изоляции: описательное исследование</article-title><trans-title-group xml:lang="en"><trans-title>Autonomic regulation of the cardiovascular system after awakening and motor activity during night sleep under conditions of prolonged isolation: A descriptive study</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0009-5891-3500</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Стулова</surname><given-names>Л. С.</given-names></name><name name-style="western" xml:lang="en"><surname>Stulova</surname><given-names>L. S.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Стулова Лидия Сергеевна</p><p>Москва</p></bio><bio xml:lang="en"><p>Moscow</p></bio><email xlink:type="simple">lidastulova@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-3564-6798</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Ковров</surname><given-names>Г. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Kovrov</surname><given-names>G. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Ковров Геннадий Васильевич, д-р биол. наук, профессор</p><p>Москва</p></bio><bio xml:lang="en"><p>Moscow</p></bio><email xlink:type="simple">kgv2006@yandex.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-2596-8929</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Черникова</surname><given-names>А. Г.</given-names></name><name name-style="western" xml:lang="en"><surname>Chernikova</surname><given-names>A. G.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Черникова Анна Григорьевна, канд. биол. наук</p><p>Москва</p></bio><bio xml:lang="en"><p>Moscow</p></bio><email xlink:type="simple">anna.imbp@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Институт медико-биологических проблем Российской академии наук</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Institute of Biomedical Problems of the Russian Academy of Sciences</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2026</year></pub-date><pub-date pub-type="epub"><day>05</day><month>10</month><year>2026</year></pub-date><volume>0</volume><issue>0</issue><issue-title>Online First</issue-title><elocation-id>526</elocation-id><permissions><copyright-statement>Copyright &amp;#x00A9; Стулова Л.С., Ковров Г.В., Черникова А.Г., 2026</copyright-statement><copyright-year>2026</copyright-year><copyright-holder xml:lang="ru">Стулова Л.С., Ковров Г.В., Черникова А.Г.</copyright-holder><copyright-holder xml:lang="en">Stulova L.S., Kovrov G.V., Chernikova A.G.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.extrememedicine.ru/jour/article/view/526">https://www.extrememedicine.ru/jour/article/view/526</self-uri><abstract><sec><title>Введение</title><p>Введение. Ночной сон — важный фактор сохранения здоровья и высокой работоспособности. В условиях стресса, например при длительной изоляции, его качество и длительность приобретают особое значение: проблемы со сном способны усиливать стрессовое состояние и ухудшать когнитивные способности. В таких условиях продолжительность сна становится решающим фактором, влияющим на самочувствие и продуктивность человека-оператора в последующий день. Однако ее роль в формировании процессов утренней активации изучена недостаточно.</p></sec><sec><title>Цель</title><p>Цель. Выявление особенностей двигательной активности во время ночного сна и вегетативной регуляции после утреннего пробуждения у лиц с различной продолжительностью сна в условиях длительного изоляционного эксперимента.</p></sec><sec><title>Материалы и методы</title><p>Материалы и методы. Исследование проводилось в рамках международного изоляционного эксперимента «SIRIUS-23/24» с участием 6 здоровых добровольцев (2 мужчин, 4 женщины, возраст 25–37 лет). По продолжительности сна участники были разделены на две группы: с коротким (&lt; 7 ч; n = 4, 2 мужчин, 2 женщины, возраст 27–37 лет) и более длительным сном (&gt; 7 ч; n = 2, 2 женщины, возраст 25 и 34 года). Ежемесячно осуществляли мониторинг двигательной активности во время сна методом актиграфии, регистрацию ЭКГ и анкетирование о характеристиках сна сразу после пробуждения. Анализировали показатели вариабельности сердечного ритма (SDNN, TP, VLF, SI, LF/HF), вегетативный индекс Кердо, а также продолжительность, эффективность сна и двигательную активность во время сна. Для оценки достоверности различий выделенных групп применялся непараметрический критерий Манна — Уитни.</p></sec><sec><title>Результаты</title><p>Результаты. У участников группы с непродолжительным сном эффективность сна была ниже, а двигательная активность в ночные часы — выше. У участников этой же группы после пробуждения выявлено относительное снижение симпатических влияний: более низкие значения частоты сердечных сокращений (61,5 уд/мин, p = 0,049), индекса Кердо (-9,4 усл. ед., p = 0,015) и SI (48 усл. ед., p = 0,04); и усиление парасимпатической активности: более высокие значения SDNN (59,3 мс, p = 0,005) и TP (1994 мс2, p = 0,006), что свидетельствует о нарушении утренней активации. В группе с более длительным сном, несмотря на лучшие показатели сна, зафиксированы более низкие значения мощности VLF после пробуждения по сравнению с группой с коротким сном (p ≤ 0,05).</p></sec><sec><title>Выводы</title><p>Выводы. В условиях длительной изоляции у некоторых членов экипажа отмечался короткий сон (&lt; 7 ч), связанный с повышенной двигательной активностью во время ночного сна, снижением эффективности сна и ослаблением симпатической регуляции сердечного ритма после пробуждения. Полученные данные подчеркивают необходимость индивидуального подхода к оптимизации режима сна для поддержания работоспособности и здоровья в экстремальных условиях.</p></sec></abstract><trans-abstract xml:lang="en"><sec><title>Introduction</title><p>Introduction. Adequate night sleep is crucial for maintaining health and optimal performance. Under chronic stressors, such as prolonged isolation, sleep quality and duration become critical determinants of resilience: sleep disturbances can exacerbate psychological distress and impair cognitive functioning. In such conditions, sleep duration becomes a crucial factor affecting the well-being and productivity of a human operator on the following day. However, its role in shaping the processes of morning activation has been insufficiently studied.</p></sec><sec><title>Objective</title><p>Objective. To identify the characteristics of motor activity during night sleep and autonomic regulation after morning awakening in individuals with different sleep durations under conditions of a prolonged isolation experiment.</p></sec><sec><title>Materials and methods</title><p>Materials and methods. The study was conducted within the framework of the international isolation experiment “SIRIUS-23/24” and involved six healthy volunteers (two men, four women; age range: 25–37 years). Based on sleep duration, participants were divided into two groups: a short-sleep group (&lt; 7 h; n = 4; two men, two women; aged 27–37) and a longer-sleep group (&gt; 7 h; n = 2; both women; aged 25 and 34). Monthly monitoring of motor activity during sleep was carried out using actigraphy, along with ECG recording and sleep characteristics questionnaires completed immediately after awakening. The following parameters were analyzed: heart rate variability indicators (SDNN, TP, VLF, SI, LF/HF), the Kerdo vegetative index, as well as sleep duration, sleep efficiency, and motor activity during sleep. To assess the significance of differences between the identified groups, the non-parametric Mann–Whitney U test was applied.</p></sec><sec><title>Results</title><p>Results. Participants in the short-sleep group demonstrated lower sleep efficiency and higher motor activity during nighttime hours. In the same group, a relative reduction in sympathetic influences was observed after awakening, evidenced by lower heart rate values (61.5 bpm, p = 0.049), Kerdo vegetative index (–9.4 arbitrary units, p = 0.015), and SI (48 arbitrary units, p = 0.04). At the same time, parasympathetic activity was enhanced, as shown by higher SDNN (59.3 ms, p = 0.005) and TP (1994 ms2, p = 0.006), indicating impaired morning activation. In the long-sleep group, despite better sleep parameters, lower VLF power values were recorded after awakening compared to the short-sleep group (p ≤ 0.05).</p></sec><sec><title>Conclusions</title><p>Conclusions. Under prolonged isolation conditions, some crew members exhibited short sleep duration (&lt; 7 h), which was associated with increased motor activity during nighttime sleep, reduced sleep efficiency, and attenuated sympathetic regulation of heart rate after awakening. These findings highlight the need for an individualized approach to sleep schedule optimization to maintain performance and health in extreme environments.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>изоляция</kwd><kwd>сон</kwd><kwd>качество сна</kwd><kwd>продолжительность сна</kwd><kwd>вариабельность сердечного ритма</kwd><kwd>двигательная активность</kwd><kwd>изоляционный эксперимент SIRIUS-23/24</kwd><kwd>циркадианный ритм</kwd></kwd-group><kwd-group xml:lang="en"><kwd>isolation</kwd><kwd>sleep</kwd><kwd>sleep quality</kwd><kwd>sleep duration</kwd><kwd>heart rate variability</kwd><kwd>motor activity</kwd><kwd>SIRIUS-23/24 isolation experiment</kwd><kwd>circadian rhythm</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Исследование выполнено в рамках темы РАН FMFR-2024–0042.</funding-statement><funding-statement xml:lang="en">The study was carried out within the framework of the RAS project FMFR-2024–0042.</funding-statement></funding-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Hyndych A, El-Abassi R, Mader ECJ. 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