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Influence of Hypoxic, Normobaric and Hypobaric Training on the Immunometabolism of Post-covid-19 Athletes

Not Applicable
Recruiting
Conditions
Normobaric Hypoxia
Hypoventilation
Normoxia
Interventions
Other: Repeated sprint
Registration Number
NCT06128941
Lead Sponsor
Faculdade de Motricidade Humana
Brief Summary

COVID-19 has significantly impacted sports globally, with event postponements, training disruptions, and wide-ranging concerns. SARS-CoV-2 infection can result in hyperinflammation and cardiopulmonary changes, with hypoxia as an aggravating sign. Hypoxia triggers complex immunometabolic mechanisms, including activation of HIF-1α and induction of HLA-G expression. Hypoxia training protocols benefit aerobic capacity and sports performance, with potential immunological impact. Studying immunometabolic markers in this context can improve athletic preparation and athletes' general health.

Detailed Description

Covid-19, caused by SARS-CoV-2, can progress to pulmonary hyperinflammation and cardiopulmonary changes, with hypoxia being one of the main signs of worsening. In hypoxia, there is activation of HIF-1 that induces the expression of HLA-G, an immuno-tolerogenic molecule that inhibits the hyperinflammatory response. Hypoxia training protocols can promote cardiopulmonary benefits and increase the expression of anti-inflammatory cytokines, HIF-1 and HLA-G. Immunometabolic markers have the potential to be used in the prevention, diagnosis, and treatment of diseases with inflammatory mechanisms. The objective of this study is to evaluate the influence of physical training protocols in hypoxic, normobaric, and hypobaric environments, on the immune, and metabolic response and cardiopulmonary behavior in athletes post covid-19, to identify potential biomarkers and better clarify the impact of exercise on immunometabolism post-covid-19. The study will consist of a randomized and controlled intervention, with training using different normobaric hypoxic methods; and an observational study at natural altitude (hypobaric hypoxia). In the normobaric hypoxia trial, participants will be divided into a control group that will carry out a training plan of repeated sprints in normoxia; and two other groups that will perform the same training sessions in normobaric hypoxia and with low lung volume voluntary hypoventilation. In the observational study with hypobaric hypoxia, high-performance resistance athletes will be recruited, who will comply with the training plan proposed by the team's coach at altitude. Cardiorespiratory, immunometabolic, neuromuscular, and autonomic fatigue, hematological indicators, plasma levels of lipid mediators, sHLA-G and cytokines, and the expression of HIF-1α in leukocyte cells will be evaluated. The analysis of the effect of the training methods will be carried out by ANOVA for repeated measures (parametric or non-parametric), or means comparison tests for paired samples (t or Wilcoxon) after evaluating the assumptions and the identification of associations between variables will be carried out by Binomial Logistic Regression Analysis.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
60
Inclusion Criteria
  • more than 5 years of training experience in an resistance modality;
  • participates in national or international championships regularly;
  • athletes convalescing from covid-19, at least 30 days after diagnosis and/or hospital discharge;
  • manifested mild to severe symptoms;
  • vaccinated or not against SARS-CoV-2;
  • antigen self-test for SARS-CoV-2 negative.
Exclusion Criteria
  • athletes who have had an acclimatization experience or exposure to altitude lasting more than 10 days in the last 6 months;
  • contain signs or symptoms of acute covid-19;
  • present a positive SARS-CoV-2 antigen self-test;
  • pregnant or postpartum women;
  • use anti-inflammatory or immunosuppressive medications.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Normobaric hypoxia (SRH)Repeated sprintParticipants will carry out training sessions in a normobaric hypoxia chamber at a simulated altitude of 3000 meters (FiO2 14.5%)
Normoxia (SRN)Repeated sprintParticipants will carry out training sessions in normoxia (FiO2 20.9%)
Hypoventilation (SRH-VLH)Repeated sprintParticipants will be asked to exhale to residual functional capacity, immediately before starting each sprint, and to hold their breath until the end of the sprint
Primary Outcome Measures
NameTimeMethod
Cytokines (TNF-α, IL-1β, IL-6, IL-10, IL-8 and IFN-γ)Before, just after and 4 weeks after the training program

ELISA

Hypoxia Inducible Factor 1 alpha (HIF-1a)Before, just after and 4 weeks after the training program

Flow cytometry for PBMCs

Human Leukocyte Antigen-G (HLA-G)Before, just after and 4 weeks after the training program

ELISA

Plasma levels of eicosanoids, endocannabinoids, steroid hormones, sphingolipids, ceramides and other glycerophospholipidsBefore, just after and 4 weeks after the training program

Mass Spectrometry (LC-MS/MS)

Hematological indicators (hematocrit, hemoglobin and cell count)Before, just after and 4 weeks after the training program

Blood count

Peak forceBefore, just after and 4 weeks after the training program

Isometric mid thigh pull

Ventilatory thresholds and maximum oxygen consumptionBefore, just after and 4 weeks after the training program

mL/kg·min

Blood lactate concentrationsBefore, just after and 4 weeks after the training program

mmol.L-1

Muscle oximetryBefore, just after and 4 weeks after the training program

Near-infrared spectroscopy (NIRS)

Secondary Outcome Measures
NameTimeMethod
Heart rateThroughout the training program, 4 weeks

maximum values during the training sessions (bpm)

Arterial oxygen saturationThroughout the training program, 4 weeks

oxymetry (%)

Subjective perception of effortThroughout the training program, 4 weeks

Adapted Borg scale

Blood pressure, heart rate and temperatureBefore, just after and 4 weeks after the training program

Values at rest mmHg, bpm and ºC

Anthropometric assessments and body compositionBefore, just after and 4 weeks after the training program

height (m), body mass (kg), fat free mass (kg), fat mass (kg)

Trial Locations

Locations (1)

Faculty of Human Kinetics

🇵🇹

Lisbon, Portugal

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