Post-COVID / Long-COVIDHydroCoVital ANCT07013903
Effects of Hydrotherapy During Post-COVID-19 Rehabilitation
A study testing Standard rehabilitation plus cold water hydrotherapy and Standard rehabilitation only in people with Post-COVID / Long-COVID and POST-Covid 19, run by Schön Klinik Berchtesgadener Land at 1 site in Germany.
Trial summary
This randomized controlled study evaluates the effects of cold water hydrotherapy as an adjunct to standard rehabilitation in patients with Post-COVID Syndrome. The primary aim is to assess changes in quality of life compared to standard rehabilitation alone. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Post-COVID / Long-COVID, POST-Covid 19, Post COVID Syndrome
- What is being tested?
- Standard rehabilitation plus cold water hydrotherapy and Standard rehabilitation only
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 50 participants
- Where
- 1 siteGermany
- Study dates
- 21 Aug 2025to 31 Oct 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Diagnosis of Post-COVID Syndrome (ICD-10 code: U08.9)
- Barthel-Index >80
- Referred to the reference center for Post-COVID rehabilitation
- Owning a smartphone to receive digital questionnaires and to use the measurement app for heart rate variability
- Written informed consent
Who cannot join
- Existing contraindications for Kneipp hydrotherapy like severe cardiovascular diseases (e.g., decompensated heart failure, unstable angina pectoris, acute myocardial infarction), severe venous diseases (e.g., acute deep vein thrombosis of the leg), severe neurological diseases (e.g., uncontrolled epilepsy)
- Prior regular practice of Kneipp applications
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Germany1 site, 1 recruiting
- Recruiting
Schön Klinik Berchtesgadener Land
Schönau am Königssee, Bavaria, 83471
Rainer Gloeckl, PhD, +498652931630, rgloeckl@schoen-klinik.de
About this study
Official title: Effects of Kneipp Hydrotherapy During Inpatient Post-Covid-19 Rehabilitation: A Randomized Controlled Trial
This randomized controlled study evaluates the effects of cold water hydrotherapy as an adjunct to standard rehabilitation in patients with Post-COVID Syndrome. The primary aim is to assess changes in quality of life compared to standard rehabilitation alone.
Read the detailed description
Patients recovering from Post-COVID Syndrome often experience persistent fatigue, autonomic dysregulation, microcirculatory disturbances, and low-grade inflammation, all of which may hinder their return to full function. Kneipp hydrotherapy-using cold water applications-can address these pathophysiological changes through several mechanisms:
Autonomic regulation: Cold stimuli trigger parasympathetic activation and improve sympathovagal balance, helping to stabilize heart rate variability and reduce symptoms of dysautonomia often seen in Post-COVID.
Enhanced microcirculation: Repeated vasoconstriction and reactive vasodilation promote endothelial function and tissue perfusion, which may alleviate muscle aches, dizziness, and fatigue by improving oxygen and nutrient delivery.
Anti-inflammatory effects: Hydrothermal stimuli have been shown to modulate cytokine profiles, increasing anti-inflammatory mediators and potentially dampening the persistent, low-grade inflammation implicated in Post-COVID pathophysiology.
Musculoskeletal recovery: Thermo-mechanical stimulation relaxes tense muscle fibers, reduces pain perception, and supports gradual increases in physical capacity, all of which are important for overcoming Post-COVID deconditioning.
Taken together, these effects suggest that adjunctive cold water hydrotherapy could accelerate functional recovery, reduce symptom burden, and enhance quality of life in Post-COVID rehabilitation.
Baseline Assessments:
At baseline, demographic data including sex, age, height, and weight will be collected. Participants will report their current main Post-COVID symptoms, which will be categorized into symptom clusters: Fatigue (A), Cognitive (B), and Somatic (C). Smoking history will be assessed, including smoking status (current, former, or never), number of cigarettes per day, years of smoking, and pack-years.
The time (in months) since the COVID-19 infection that led to Post-COVID syndrome will be documented, along with the number of COVID-19 vaccinations received at the time of infection. Employment status will be recorded, distinguishing between full-time or part-time employment, COVID-related work disability, retirement, unemployment, or disability pension.
Comorbidities will be documented across the following categories: cardiovascular, pulmonary, cerebrovascular, metabolic, musculoskeletal, psychiatric, and other conditions. The severity of the acute COVID-19 illness will be assessed using the WHO Clinical Progression Scale, including information on any hospital admission and length of stay (in days).
Pulmonary function testing at baseline (V1) will include FEV₁, FVC, FEV₁/FVC ratio, and total lung capacity (TLC), all expressed as percent predicted. Autonomic function will be evaluated using the Schellong test. Vascular status will be assessed by four-limb blood pressure measurement. Additionally, self-reported work ability and the number of Post-COVID-related sick leave days within the past 12 weeks will be recorded.
- Being tested
- Standard rehabilitation plus cold water hydrotherapy, Standard rehabilitation only
- Keywords
- rehabilitation, therapy, Post-COVID, Long COVID, intervention, hydrotherapy, Kneipp, balneotherapy, Post-COVID condition, quality of life
- Medical subject headings
- Post-Acute COVID-19 Syndrome
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Standard rehabilitation plus cold water hydrotherapyOther
Cold water hydrotherapy (5-10 minutes each), twice daily during the 3-week multimodal inpatient rehabilitation program and once daily during the 6-month follow-up period
Standard rehabilitation onlyOther
same rehabilitation program than the experimental group but without hydrotherapy
| Study group | Role | What they receive |
|---|---|---|
| Post-COVID Rehabilitation with hydrotherapy | Experimental | Cold water hydrotherapy (5-10 minutes each), twice daily during the 3-week multimodal inpatient rehabilitation program and once daily during the 6-month follow-up period Receives: Other: Standard rehabilitation plus cold water hydrotherapy |
| Post-COVID Rehabilitation without hydrotherapy | Active comparator | 3-week inpatient multimodal inpatient rehabilitation program without hydrotherapy Receives: Other: Standard rehabilitation only |
What is being measured
The primary outcome is the main question the study is designed to answer.
Health-related quality of life by Short Form-12 Health Survey (SF-12)
Change in the Short Form-12 physical and mental component summary scores
Measured: From baseline (Visit 1) to end of inpatient rehabilitation (3 weeks, Visit 2)
Secondary outcomes (13)
Fatigue severity by Fatigue Severity Scale
Change in Fatigue Severity Scale score
Measured: From baseline (Visit 1) to end of inpatient rehabilitation (3 weeks, Visit 2)
Sleep quality by Pittsburgh Sleep Quality Index
Change in Pittsburgh Sleep Quality Index score
Measured: From baseline (Visit 1) to end of inpatient rehabilitation (3 weeks, Visit 2)
Health status by EuroQol-5 Dimensions-5 Levels
Change in EuroQol-5 Dimensions-5 Levels questionnaire score
Measured: From baseline (Visit 1) to end of inpatient rehabilitation (3 weeks, Visit 2)
Autonomic function (heart rate variability by photoplethysmography)
Change in heart rate variability (root mean square of successive differences) measured by Kyto 2935 via photoplethysmography
Measured: Daily during first 3 weeks of rehabilitation (Visit 1 to Visit 2)
Resting blood pressure (systolic and diastolic)
Change in morning resting systolic and diastolic blood pressure
Measured: Daily during first 3 weeks of rehabilitation (Visit 1 to Visit 2)
Post-COVID work-absence days
Number of days of work absence due to Post-COVID-19 symptoms during the past 12-weeks
Measured: From baseline (Visit 1) to 3 months (Visit 3) and to 6 months (Visit 4)
Long-term quality of life by Short Form-12
Change in Short Form-12 scores at follow-up
Measured: From baseline (Visit 1) to 3 months (Visit 3) and to 6 months (Visit 4)
Long-term fatigue by Fatigue Severity Scale
Change in Fatigue Severity Scale score at follow-up
Measured: From baseline (Visit 1) to 3 months (Visit 3) and to 6 months (Visit 4)
Adherence to hydrotherapy
Proportion of prescribed hydrotherapy applications in the intervention group performed, as recorded in diary or app.
Short-term Adherence: During the 3-week intervention phase, patients are considered "adherent" if they perform at least one hydrotherapy session per day on at least 75% of study days. We will compare health improvements between high-adherence and low-adherence participants.
Long-term Adherence and Effects: Over the 3- and 6-month follow-up, "adherent" patients are those who continue self-administered hydrotherapy at least four times per week on at least 75% of follow-up weeks. We will assess whether these patients sustain greater gains in quality of life.
Measured: During the 3-week intervention phase (up to Visit 2) and over the 6-month follow-up period (to Visit 4)
Adverse events recording
Number and severity of adverse events related to Kneipp hydrotherapy
Measured: From start of intervention (Visit 1) through end of study (Visit 4, 6-month follow-up)
Long-term heart rate variability changes (HRV)
Change in heart rate variability parameters (root mean square of successive differences) measured by photoplethysmography. At follow-up visits patients will measure HRV for 7 consecutive days
Measured: From baseline (Visit 1) to 3 months (Visit 3) and to 6 months (Visit 4)
Post-exertional malaise severity
Change in Post-Exertional Malaise score measured by the DePaul Symptom Questionnaire-Post-Exertional Malaise
Measured: From baseline (Visit 1) to 6-month (Visit 4) follow-up
Daily well-being documentation
Self-reported daily well-being recorded via digital diary on a scale from 0 to 100
Measured: Daily throughout the intervention and 6 months follow-up phase (Visit 1 to Visit 4)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted10 Jun 2025
- Study start21 Aug 2025
- Primary completion31 Jan 2027 (estimated)
- Study completion31 Oct 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Post-COVID / Long-COVIDStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 50 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Schön Klinik Berchtesgadener Land
- Sponsor type
- University, hospital or other
- Collaborators
- Bavarian Health and Food Safety Authority (LGL)
- Responsible party
- Principal investigator, Prof. Dr. Andreas Rembert Koczulla, Schön Klinik Berchtesgadener Land
- Investigators
- Rembert Koczulla, MD, Principal investigator, Schön Klinik Berchtesgadener Land
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07013903
- Sponsor's protocol ID
- HydroCoVital A
- Acronym
- HydroCoVital A
- Status last verified
- Aug 2025
- First submitted
- 5 Jun 2025
- Last updated
- 28 Aug 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 28 Aug 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Effects of Kneipp Hydrotherapy During Inpatient Post-Covid-19 Rehabilitation: A Randomized Controlled Trial
- ClinicalTrials.gov ID
- NCT07013903
- Acronym / sponsor ID
- HydroCoVital A / HydroCoVital A
- Keywords
- rehabilitation, therapy, Post-COVID, Long COVID, intervention, hydrotherapy, Kneipp, balneotherapy
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 50 participants (estimated)
- Lead sponsor
- Schön Klinik Berchtesgadener LandUniversity, hospital or other
- Collaborators
- Bavarian Health and Food Safety Authority (LGL)
- Study start
- 21 Aug 2025 (actual)
- Primary completion
- 31 Jan 2027 (estimated)
- Study completion
- 31 Oct 2027 (estimated)
- First posted
- 10 Jun 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This randomized controlled study evaluates the effects of cold water hydrotherapy as an adjunct to standard rehabilitation in patients with Post-COVID Syndrome. The primary aim is to assess changes in quality of life compared to standard rehabilitation alone.
Detailed description
Patients recovering from Post-COVID Syndrome often experience persistent fatigue, autonomic dysregulation, microcirculatory disturbances, and low-grade inflammation, all of which may hinder their return to full function. Kneipp hydrotherapy-using cold water applications-can address these pathophysiological changes through several mechanisms:
Autonomic regulation: Cold stimuli trigger parasympathetic activation and improve sympathovagal balance, helping to stabilize heart rate variability and reduce symptoms of dysautonomia often seen in Post-COVID.
Enhanced microcirculation: Repeated vasoconstriction and reactive vasodilation promote endothelial function and tissue perfusion, which may alleviate muscle aches, dizziness, and fatigue by improving oxygen and nutrient delivery.
Anti-inflammatory effects: Hydrothermal stimuli have been shown to modulate cytokine profiles, increasing anti-inflammatory mediators and potentially dampening the persistent, low-grade inflammation implicated in Post-COVID pathophysiology.
Musculoskeletal recovery: Thermo-mechanical stimulation relaxes tense muscle fibers, reduces pain perception, and supports gradual increases in physical capacity, all of which are important for overcoming Post-COVID deconditioning.
Taken together, these effects suggest that adjunctive cold water hydrotherapy could accelerate functional recovery, reduce symptom burden, and enhance quality of life in Post-COVID rehabilitation.
Baseline Assessments:
At baseline, demographic data including sex, age, height, and weight will be collected. Participants will report their current main Post-COVID symptoms, which will be categorized into symptom clusters: Fatigue (A), Cognitive (B), and Somatic (C). Smoking history will be assessed, including smoking status (current, former, or never), number of cigarettes per day, years of smoking, and pack-years.
The time (in months) since the COVID-19 infection that led to Post-COVID syndrome will be documented, along with the number of COVID-19 vaccinations received at the time of infection. Employment status will be recorded, distinguishing between full-time or part-time employment, COVID-related work disability, retirement, unemployment, or disability pension.
Comorbidities will be documented across the following categories: cardiovascular, pulmonary, cerebrovascular, metabolic, musculoskeletal, psychiatric, and other conditions. The severity of the acute COVID-19 illness will be assessed using the WHO Clinical Progression Scale, including information on any hospital admission and length of stay (in days).
Pulmonary function testing at baseline (V1) will include FEV₁, FVC, FEV₁/FVC ratio, and total lung capacity (TLC), all expressed as percent predicted. Autonomic function will be evaluated using the Schellong test. Vascular status will be assessed by four-limb blood pressure measurement. Additionally, self-reported work ability and the number of Post-COVID-related sick leave days within the past 12 weeks will be recorded.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Post-COVID Rehabilitation with hydrotherapy | Experimental | Other: Standard rehabilitation plus cold water hydrotherapyCold water hydrotherapy (5-10 minutes each), twice daily during the 3-week multimodal inpatient rehabilitation program and once daily during the 6-month follow-up period |
| Post-COVID Rehabilitation without hydrotherapy | Active comparator | Other: Standard rehabilitation only3-week inpatient multimodal inpatient rehabilitation program without hydrotherapy |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- Diagnosis of Post-COVID Syndrome (ICD-10 code: U08.9)
- Barthel-Index >80
- Referred to the reference center for Post-COVID rehabilitation
- Owning a smartphone to receive digital questionnaires and to use the measurement app for heart rate variability
- Written informed consent
Key exclusion criteria (2 listed)
- Existing contraindications for Kneipp hydrotherapy like severe cardiovascular diseases (e.g., decompensated heart failure, unstable angina pectoris, acute myocardial infarction), severe venous diseases (e.g., acute deep vein thrombosis of the leg), severe neurological diseases (e.g., uncontrolled epilepsy)
- Prior regular practice of Kneipp applications
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Standard rehabilitation plus cold water hydrotherapyCold water hydrotherapy (5-10 minutes each), twice daily during the 3-week multimodal inpatient rehabilitation program and once daily during the 6-month follow-up period | Other | Post-COVID Rehabilitation with hydrotherapy |
| Standard rehabilitation onlysame rehabilitation program than the experimental group but without hydrotherapy | Other | Post-COVID Rehabilitation without hydrotherapy |
Primary outcome
Health-related quality of life by Short Form-12 Health Survey (SF-12)
Time frame: From baseline (Visit 1) to end of inpatient rehabilitation (3 weeks, Visit 2)
Change in the Short Form-12 physical and mental component summary scores
13 secondary outcomes
Fatigue severity by Fatigue Severity Scale
Time frame: From baseline (Visit 1) to end of inpatient rehabilitation (3 weeks, Visit 2)
Sleep quality by Pittsburgh Sleep Quality Index
Time frame: From baseline (Visit 1) to end of inpatient rehabilitation (3 weeks, Visit 2)
Health status by EuroQol-5 Dimensions-5 Levels
Time frame: From baseline (Visit 1) to end of inpatient rehabilitation (3 weeks, Visit 2)
Autonomic function (heart rate variability by photoplethysmography)
Time frame: Daily during first 3 weeks of rehabilitation (Visit 1 to Visit 2)
Resting blood pressure (systolic and diastolic)
Time frame: Daily during first 3 weeks of rehabilitation (Visit 1 to Visit 2)
Post-COVID work-absence days
Time frame: From baseline (Visit 1) to 3 months (Visit 3) and to 6 months (Visit 4)
Long-term quality of life by Short Form-12
Time frame: From baseline (Visit 1) to 3 months (Visit 3) and to 6 months (Visit 4)
Long-term fatigue by Fatigue Severity Scale
Time frame: From baseline (Visit 1) to 3 months (Visit 3) and to 6 months (Visit 4)
Adherence to hydrotherapy
Time frame: During the 3-week intervention phase (up to Visit 2) and over the 6-month follow-up period (to Visit 4)
Adverse events recording
Time frame: From start of intervention (Visit 1) through end of study (Visit 4, 6-month follow-up)
Long-term heart rate variability changes (HRV)
Time frame: From baseline (Visit 1) to 3 months (Visit 3) and to 6 months (Visit 4)
Post-exertional malaise severity
Time frame: From baseline (Visit 1) to 6-month (Visit 4) follow-up
Daily well-being documentation
Time frame: Daily throughout the intervention and 6 months follow-up phase (Visit 1 to Visit 4)
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 28 Aug 2025.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Rembert Koczulla, MD principal investigator
Schön Klinik Berchtesgadener Land
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Standard rehabilitation plus cold water hydrotherapy and Standard rehabilitation only in people with Post-COVID / Long-COVID and POST-Covid 19, run by Schön Klinik Berchtesgadener Land at 1 site in Germany.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 2 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 28 Aug 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Germany. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Rainer Gloeckl, PhD (+498652931630, rgloeckl@schoen-klinik.de), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Health-related quality of life by Short Form-12 Health Survey (SF-12) (time frame: From baseline (Visit 1) to end of inpatient rehabilitation (3 weeks, Visit 2)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 28 Aug 2025.