Fasting ConditionsFASTEXNCT07847658
Effects of the Buchinger Wilhelmi Fasting Program and Exercise on Physical Fitness and Sleep Quality
A study testing Buchinger Wilhelmi prolonged fasting, Online exercise program and Supervised exercise program during prolonged fasting in people with Fasting Conditions and Metabolic Health, run by Universidad de Almeria at 1 site in Spain.
Trial summary
Type of Study: Clinical Trial Goal: The goal of this clinical trial is to investigate whether combining the Buchinger Wilhelmi prolonged fasting program with a structured exercise program can improve physical fitness, body composition, cardiometabolic health, sleep quality, and health-related quality of life. Read more about this study
- Who is it for?
- Ages 18 to 80 yearsHealthy volunteers can take part
- Conditions the study is for
- Fasting Conditions, Metabolic Health
- What is being tested?
- Buchinger Wilhelmi prolonged fasting, Online exercise program and Supervised exercise program during prolonged fasting
- Type of treatment
- Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 100 participants
- Where
- 1 siteSpain
- Study dates
- Jan 2027to Jan 2030
- 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 to 80 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Men and women aged 18-80 years.
- Undergoing the Buchinger Wilhelmi prolonged fasting program at the Buchinger Wilhelmi Clinic in Marbella for at least 4 consecutive days.
- Medically eligible to undergo prolonged fasting and to complete the study assessments.
- For participants choosing an exercise condition, medically eligible to participate in the corresponding exercise program.
- Able to understand the study procedures and provide written informed consent.
Who cannot join
- Any medical condition or functional limitation that significantly restricts mobility or prevents safe completion of the study assessments or, when applicable, the exercise program.
- Pregnancy or breastfeeding.
- Cognitive or communication impairment that prevents adequate understanding of the study procedures or provision of informed consent.
- Concurrent participation in another interventional study that could interfere with the study procedures or outcomes.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
About this study
Official title: Fasting Meets Fitness: Unlocking the Synergy Between BW Protocol, Exercise, and Sleep Quality - A Clinical Study
Type of Study: Clinical Trial
Goal: The goal of this clinical trial is to investigate whether combining the Buchinger Wilhelmi prolonged fasting program with a structured exercise program can improve physical fitness, body composition, cardiometabolic health, sleep quality, and health-related quality of life. The study will also investigate metabolic responses to prolonged fasting and whether these responses are influenced by exercise.
Read more
Participant Population/Health Conditions: The study will involve adults attending the Buchinger Wilhelmi Clinic who undergo the prolonged fasting program and meet the study eligibility criteria.
Main Questions:
- Does structured exercise performed before and/or during prolonged fasting enhance its effects on physical fitness, body composition, and cardiometabolic health?
- Does structured exercise improve sleep quality and health-related quality of life during prolonged fasting?
Participants Will:
- Undergo the Buchinger Wilhelmi prolonged fasting program.
- Choose whether to complete an online exercise program before the clinical stay and/or a supervised exercise program during fasting.
- Undergo physiological, physical fitness, and body composition assessments before and after the intervention.
- Provide blood samples to assess cardiometabolic and metabolic responses.
- Complete assessments of sleep and health-related quality of life.
Comparison Groups: Researchers will compare the four study conditions to determine whether structured exercise performed before and/or during prolonged fasting enhances the physiological, metabolic, and functional effects of the Buchinger Wilhelmi fasting program.
Read the detailed description
Prolonged fasting induces substantial metabolic adaptations, including increased ketone body production and changes in glucose and lipid metabolism, and has been associated with improvements in cardiometabolic health and body composition. However, fasting may also be accompanied by fatigue, sleep disturbances, and changes in well-being that can affect physical function and quality of life during the intervention.
Exercise is a potent non-pharmacological strategy for improving physical fitness, body composition, cardiometabolic health, sleep, and quality of life. Combining exercise with prolonged fasting may provide complementary benefits by enhancing fasting-induced metabolic adaptations while helping to maintain physical function and well-being. The timing of exercise may also be relevant, as exercise performed before the fasting period may influence the physiological response to fasting, while exercise performed during fasting may directly interact with fasting-induced changes in substrate utilization and energy metabolism.
Based on this rationale, the main hypothesis is that structured exercise performed before and/or during prolonged fasting enhances the physiological and metabolic effects of fasting while improving physical fitness, sleep, and quality of life. The main objective is to determine the independent and combined effects of exercise performed before and during the Buchinger Wilhelmi prolonged fasting program on physical fitness, body composition, cardiometabolic health, sleep, and health-related quality of life.
The study will involve adults undergoing the Buchinger Wilhelmi prolonged fasting program as part of their clinical stay. Participants will choose whether to complete an online exercise program before attending the clinic and whether to participate in a supervised exercise program specifically designed for the fasting period during their clinical stay. These choices will result in four study conditions: (1) online exercise followed by prolonged fasting alone; (2) online exercise followed by prolonged fasting combined with supervised exercise; (3) prolonged fasting alone; and (4) prolonged fasting combined with supervised exercise. Allocation to these conditions will not be randomized. During fasting, participants will receive approximately 200-250 kcal/day and may participate in the activities routinely available at the clinic.
Before and after the intervention, participants will undergo physiological and physical fitness assessments. Blood samples will be collected to assess cardiometabolic and metabolic responses, including glucose and lipid metabolism and ketone production. Body composition will be assessed using bioelectrical impedance analysis, and physical fitness will include handgrip and lower-limb strength assessments. Sleep will be evaluated objectively using accelerometry and subjectively using the Pittsburgh Sleep Quality Index, while health-related quality of life will be assessed using the SF-36 questionnaire. These assessments are consistent with those specified in the study protocol.
By comparing the four study conditions, the study aims to determine whether structured exercise performed before and/or during prolonged fasting enhances fasting-induced metabolic adaptations and improves physical fitness, body composition, sleep, and health-related quality of life.
- Conditions
- Fasting Conditions, Metabolic Health
- Being tested
- Buchinger Wilhelmi prolonged fasting, Online exercise program, Supervised exercise program during prolonged fasting
- Keywords
- Prolonged fasting, Buchinger Wilhelmi fasting, Physical exercise, Cardiometabolic health, Physical fitness
- Medical subject headings
- Motor Activity
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Buchinger Wilhelmi prolonged fastingBehavioural
Participants will undergo the medically supervised Buchinger Wilhelmi prolonged fasting program for at least 4 consecutive days. During fasting, participants will receive approximately 200-250 kcal/day, primarily from vegetable juices and vegetable broth, together with non-caloric fluids.
Online exercise programBehavioural
Participants will complete a 21-day study-specific remotely delivered exercise program before admission to the Buchinger Wilhelmi Clinic. The program provides structured exercise training before the prolonged fasting period.
Supervised exercise program during prolonged fastingBehavioural
Participants will complete a study-specific supervised exercise program during the prolonged fasting period at the Buchinger Wilhelmi Clinic. Exercise sessions will be conducted under professional supervision and adapted to participants' individual physical capacity.
| Study group | Role | What they receive |
|---|---|---|
| Prolonged fasting | Experimental | Participants will undergo the Buchinger Wilhelmi prolonged fasting program for at least 4 consecutive days without completing the study-specific online exercise program before the clinical stay or the supervised exercise program during fasting. Receives: Behavioral: Buchinger Wilhelmi prolonged fasting |
| Prolonged fasting + supervised exercise | Experimental | Participants will undergo the Buchinger Wilhelmi prolonged fasting program for at least 4 consecutive days and participate in the study-specific supervised exercise program during the fasting period. Participants will not complete the online exercise program before the clinical stay. Receives: Behavioral: Buchinger Wilhelmi prolonged fasting; Behavioral: Supervised exercise program during prolonged fasting |
| Online exercise + prolonged fasting | Experimental | Participants will complete a 21-day study-specific online exercise program before the clinical stay and subsequently undergo the Buchinger Wilhelmi prolonged fasting program for at least 4 consecutive days without participating in the supervised exercise program during fasting. Receives: Behavioral: Buchinger Wilhelmi prolonged fasting; Behavioral: Online exercise program |
| Online exercise + prolonged fasting + supervised exercise | Experimental | Participants will complete a 21-day study-specific online exercise program before the clinical stay and subsequently undergo the Buchinger Wilhelmi prolonged fasting program for at least 4 consecutive days combined with the study-specific supervised exercise program during fasting. Receives: Behavioral: Buchinger Wilhelmi prolonged fasting; Behavioral: Online exercise program; Behavioral: Supervised exercise program during prolonged fasting |
What is being measured
The primary outcome is the main question the study is designed to answer.
Handgrip Strength
Change from baseline in mean bilateral handgrip strength (kg) to the end of the fasting period, assessed using a handgrip dynamometer. For each hand, three trials will be performed and averaged. The mean values obtained for the right and left hands will then be averaged to obtain one bilateral handgrip strength value per participant.
Measured: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Secondary outcomes (17)
Fasting Blood Glucose
Change in fasting blood glucose concentration (mg/dL) from baseline to the end of the fasting period.
Measured: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Fasting Insulin
Change in fasting insulin concentration (µIU/mL) from baseline to the end of the fasting period.
Measured: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
LDL Cholesterol
Change in low-density lipoprotein cholesterol concentration (mg/dL) from baseline to the end of the fasting period.
Measured: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
HDL Cholesterol
Change in high-density lipoprotein cholesterol concentration (mg/dL) from baseline to the end of the fasting period.
Measured: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Triglycerides
Change in triglyceride concentration (mg/dL) from baseline to the end of the fasting period.
Measured: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
C-Reactive Protein
Change in C-reactive protein concentration (mg/L) from baseline to the end of the fasting period.
Measured: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Five-Times Sit-to-Stand Test
Change in the time required to complete five consecutive sit-to-stand repetitions (seconds) from baseline to the end of the fasting period.
Measured: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
30-Second Sit-to-Stand Test
Change in the number of complete sit-to-stand repetitions performed within 30 seconds (repetitions) from baseline to the end of the fasting period.
Measured: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Blood Lactate Response to the 30-Second Sit-to-Stand Test
Change from baseline to the end of the fasting period in the blood lactate response to the 30-second sit-to-stand test, calculated as post-exercise blood lactate minus pre-exercise blood lactate (Δ lactate; mmol/L) at each assessment.
Measured: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Total Body Fat Mass
Change in total body fat mass (kg) from baseline to the end of the fasting period, assessed by dual-energy X-ray absorptiometry (DXA).
Measured: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Body Fat Percentage
Change in total body fat percentage (%) from baseline to the end of the fasting period, assessed by DXA.
Measured: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Total Lean Mass
Change in total lean mass (kg) from baseline to the end of the fasting period, assessed by DXA.
Measured: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Visceral Adipose Tissue Fat Mass
Change in visceral adipose tissue (VAT) fat mass (g) from baseline to the end of the fasting period, assessed by dual-energy X-ray absorptiometry (DXA).
Measured: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Subcutaneous Adipose Tissue Fat Mass
Change in subcutaneous adipose tissue (SAT) fat mass (g) from baseline to the end of the fasting period, assessed by dual-energy X-ray absorptiometry (DXA).
Measured: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Physical Activity - International Physical Activity Questionnaire (IPAQ)
Change in self-reported physical activity (MET-min/week) from baseline to the end of the fasting period, assessed using the International Physical Activity Questionnaire (IPAQ). Higher MET-min/week values indicate greater physical activity.
Measured: Baseline; Day 4 to Day 28 (final fasting day, depending on participant); and 30 days after the final fasting day
Pittsburgh Sleep Quality Index (PSQI)
Change from baseline in subjective sleep quality assessed using the Pittsburgh Sleep Quality Index (PSQI) global score (0-21 points). Higher scores indicate poorer subjective sleep quality.
Measured: Baseline; Day 4 to Day 28 (final fasting day, depending on participant); and 30 days after the final fasting day
Health-Related Quality of Life - SF-36
Change in health-related quality of life assessed using the 36-Item Short Form Health Survey (SF-36). The eight domains assessed are physical functioning, role limitations due to physical health, bodily pain, general health, vitality, social functioning, role limitations due to emotional problems, and mental health (each scored from 0 to 100 points). Higher scores indicate better health status.
Measured: Baseline; Day 4 to Day 28 (final fasting day, depending on participant); and 30 days after the final fasting day
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted29 Sep 2026
- Study startJan 2027 (estimated)
- Primary completionJan 2030 (estimated)
- Study completionJan 2030 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Fasting ConditionsStudies 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
- Other
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Model description
- This study will consist of a non-randomized clinical trial including adults undergoing the Buchinger Wilhelmi prolonged fasting program. Participants will self-select whether to complete an online exercise program before the clinical stay and whether to participate in a supervised exercise program specifically designed for the fasting period. This will result in four parallel groups: prolonged fasting alone; prolonged fasting plus supervised exercise; online exercise followed by prolonged fasting alone; or online exercise followed by prolonged fasting plus supervised exercise. During prolonged fasting, participants will receive approximately 200-250 kcal/day. Participants will be enrolled prospectively and continuously as they attend the clinic.
- Masking
- None (open label)
- Enrolment
- 100 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Universidad de Almeria
- Sponsor type
- University, hospital or other
- Collaborators
- Buchinger Wilhelmi Development & Holding GmbH
- Responsible party
- Principal investigator, Borja Martínez Tellez, Universidad de Almeria
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07847658
- Sponsor's protocol ID
- UALBIO2025/030
- Acronym
- FASTEX
- Status last verified
- Sep 2026
- First submitted
- 17 Sep 2026
- Last updated
- 29 Sep 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes
Study at a glance
From the registry record, last updated by the sponsor on 29 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Fasting Meets Fitness: Unlocking the Synergy Between BW Protocol, Exercise, and Sleep Quality - A Clinical Study
- ClinicalTrials.gov ID
- NCT07847658
- Acronym / sponsor ID
- FASTEX / UALBIO2025/030
- Conditions
- Fasting Conditions, Metabolic Health
- Keywords
- Prolonged fasting, Buchinger Wilhelmi fasting, Physical exercise, Cardiometabolic health, Physical fitness
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 100 participants (estimated)
- Lead sponsor
- Universidad de AlmeriaUniversity, hospital or other
- Collaborators
- Buchinger Wilhelmi Development & Holding GmbH
- Study start
- Jan 2027 (estimated)
- Primary completion
- Jan 2030 (estimated)
- Study completion
- Jan 2030 (estimated)
- First posted
- 29 Sep 2026 (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.
Type of Study: Clinical Trial
Goal: The goal of this clinical trial is to investigate whether combining the Buchinger Wilhelmi prolonged fasting program with a structured exercise program can improve physical fitness, body composition, cardiometabolic health, sleep quality, and health-related quality of life. The study will also investigate metabolic responses to prolonged fasting and whether these responses are influenced by exercise.
Participant Population/Health Conditions: The study will involve adults attending the Buchinger Wilhelmi Clinic who undergo the prolonged fasting program and meet the study eligibility criteria.
Main Questions:
- Does structured exercise performed before and/or during prolonged fasting enhance its effects on physical fitness, body composition, and cardiometabolic health?
- Does structured exercise improve sleep quality and health-related quality of life during prolonged fasting?
Participants Will:
- Undergo the Buchinger Wilhelmi prolonged fasting program.
- Choose whether to complete an online exercise program before the clinical stay and/or a supervised exercise program during fasting.
- Undergo physiological, physical fitness, and body composition assessments before and after the intervention.
- Provide blood samples to assess cardiometabolic and metabolic responses.
- Complete assessments of sleep and health-related quality of life.
Comparison Groups: Researchers will compare the four study conditions to determine whether structured exercise performed before and/or during prolonged fasting enhances the physiological, metabolic, and functional effects of the Buchinger Wilhelmi fasting program.
Detailed description
Prolonged fasting induces substantial metabolic adaptations, including increased ketone body production and changes in glucose and lipid metabolism, and has been associated with improvements in cardiometabolic health and body composition. However, fasting may also be accompanied by fatigue, sleep disturbances, and changes in well-being that can affect physical function and quality of life during the intervention.
Exercise is a potent non-pharmacological strategy for improving physical fitness, body composition, cardiometabolic health, sleep, and quality of life. Combining exercise with prolonged fasting may provide complementary benefits by enhancing fasting-induced metabolic adaptations while helping to maintain physical function and well-being. The timing of exercise may also be relevant, as exercise performed before the fasting period may influence the physiological response to fasting, while exercise performed during fasting may directly interact with fasting-induced changes in substrate utilization and energy metabolism.
Based on this rationale, the main hypothesis is that structured exercise performed before and/or during prolonged fasting enhances the physiological and metabolic effects of fasting while improving physical fitness, sleep, and quality of life. The main objective is to determine the independent and combined effects of exercise performed before and during the Buchinger Wilhelmi prolonged fasting program on physical fitness, body composition, cardiometabolic health, sleep, and health-related quality of life.
The study will involve adults undergoing the Buchinger Wilhelmi prolonged fasting program as part of their clinical stay. Participants will choose whether to complete an online exercise program before attending the clinic and whether to participate in a supervised exercise program specifically designed for the fasting period during their clinical stay. These choices will result in four study conditions: (1) online exercise followed by prolonged fasting alone; (2) online exercise followed by prolonged fasting combined with supervised exercise; (3) prolonged fasting alone; and (4) prolonged fasting combined with supervised exercise. Allocation to these conditions will not be randomized. During fasting, participants will receive approximately 200-250 kcal/day and may participate in the activities routinely available at the clinic.
Before and after the intervention, participants will undergo physiological and physical fitness assessments. Blood samples will be collected to assess cardiometabolic and metabolic responses, including glucose and lipid metabolism and ketone production. Body composition will be assessed using bioelectrical impedance analysis, and physical fitness will include handgrip and lower-limb strength assessments. Sleep will be evaluated objectively using accelerometry and subjectively using the Pittsburgh Sleep Quality Index, while health-related quality of life will be assessed using the SF-36 questionnaire. These assessments are consistent with those specified in the study protocol.
By comparing the four study conditions, the study aims to determine whether structured exercise performed before and/or during prolonged fasting enhances fasting-induced metabolic adaptations and improves physical fitness, body composition, sleep, and health-related quality of life.
Study design
- Primary purpose
- Other
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 4
- Model description
- This study will consist of a non-randomized clinical trial including adults undergoing the Buchinger Wilhelmi prolonged fasting program. Participants will self-select whether to complete an online exercise program before the clinical stay and whether to participate in a supervised exercise program specifically designed for the fasting period. This will result in four parallel groups: prolonged fasting alone; prolonged fasting plus supervised exercise; online exercise followed by prolonged fasting alone; or online exercise followed by prolonged fasting plus supervised exercise. During prolonged fasting, participants will receive approximately 200-250 kcal/day. Participants will be enrolled prospectively and continuously as they attend the clinic.
| Arm | Type | Receives |
|---|---|---|
| Prolonged fasting | Experimental | Behavioral: Buchinger Wilhelmi prolonged fastingParticipants will undergo the Buchinger Wilhelmi prolonged fasting program for at least 4 consecutive days without completing the study-specific online exercise program before the clinical stay or the supervised exercise program during fasting. |
| Prolonged fasting + supervised exercise | Experimental | Behavioral: Buchinger Wilhelmi prolonged fasting, Behavioral: Supervised exercise program during prolonged fastingParticipants will undergo the Buchinger Wilhelmi prolonged fasting program for at least 4 consecutive days and participate in the study-specific supervised exercise program during the fasting period. Participants will not complete the online exercise program before the clinical stay. |
| Online exercise + prolonged fasting | Experimental | Behavioral: Buchinger Wilhelmi prolonged fasting, Behavioral: Online exercise programParticipants will complete a 21-day study-specific online exercise program before the clinical stay and subsequently undergo the Buchinger Wilhelmi prolonged fasting program for at least 4 consecutive days without participating in the supervised exercise program during fasting. |
| Online exercise + prolonged fasting + supervised exercise | Experimental | Behavioral: Buchinger Wilhelmi prolonged fasting, Behavioral: Online exercise program, Behavioral: Supervised exercise program during prolonged fastingParticipants will complete a 21-day study-specific online exercise program before the clinical stay and subsequently undergo the Buchinger Wilhelmi prolonged fasting program for at least 4 consecutive days combined with the study-specific supervised exercise program during fasting. |
Who may qualify
- Ages
- 18 to 80 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- Men and women aged 18-80 years.
- Undergoing the Buchinger Wilhelmi prolonged fasting program at the Buchinger Wilhelmi Clinic in Marbella for at least 4 consecutive days.
- Medically eligible to undergo prolonged fasting and to complete the study assessments.
- For participants choosing an exercise condition, medically eligible to participate in the corresponding exercise program.
- Able to understand the study procedures and provide written informed consent.
Key exclusion criteria (4 listed)
- Any medical condition or functional limitation that significantly restricts mobility or prevents safe completion of the study assessments or, when applicable, the exercise program.
- Pregnancy or breastfeeding.
- Cognitive or communication impairment that prevents adequate understanding of the study procedures or provision of informed consent.
- Concurrent participation in another interventional study that could interfere with the study procedures or outcomes.
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 |
|---|---|---|
| Buchinger Wilhelmi prolonged fastingParticipants will undergo the medically supervised Buchinger Wilhelmi prolonged fasting program for at least 4 consecutive days. During fasting, participants will receive approximately 200-250 kcal/day, primarily from vegetable juices and vegetable broth, together with non-caloric fluids. | Behavioural | Online exercise + prolonged fasting, Online exercise + prolonged fasting + supervised exercise, Prolonged fasting, Prolonged fasting + supervised exercise |
| Online exercise programParticipants will complete a 21-day study-specific remotely delivered exercise program before admission to the Buchinger Wilhelmi Clinic. The program provides structured exercise training before the prolonged fasting period. | Behavioural | Online exercise + prolonged fasting, Online exercise + prolonged fasting + supervised exercise |
| Supervised exercise program during prolonged fastingParticipants will complete a study-specific supervised exercise program during the prolonged fasting period at the Buchinger Wilhelmi Clinic. Exercise sessions will be conducted under professional supervision and adapted to participants' individual physical capacity. | Behavioural | Online exercise + prolonged fasting + supervised exercise, Prolonged fasting + supervised exercise |
Primary outcome
Handgrip Strength
Time frame: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Change from baseline in mean bilateral handgrip strength (kg) to the end of the fasting period, assessed using a handgrip dynamometer. For each hand, three trials will be performed and averaged. The mean values obtained for the right and left hands will then be averaged to obtain one bilateral handgrip strength value per participant.
17 secondary outcomes
Fasting Blood Glucose
Time frame: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Fasting Insulin
Time frame: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
LDL Cholesterol
Time frame: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
HDL Cholesterol
Time frame: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Triglycerides
Time frame: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
C-Reactive Protein
Time frame: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Five-Times Sit-to-Stand Test
Time frame: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
30-Second Sit-to-Stand Test
Time frame: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Blood Lactate Response to the 30-Second Sit-to-Stand Test
Time frame: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Total Body Fat Mass
Time frame: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Body Fat Percentage
Time frame: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Total Lean Mass
Time frame: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Visceral Adipose Tissue Fat Mass
Time frame: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Subcutaneous Adipose Tissue Fat Mass
Time frame: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)
Physical Activity - International Physical Activity Questionnaire (IPAQ)
Time frame: Baseline; Day 4 to Day 28 (final fasting day, depending on participant); and 30 days after the final fasting day
Pittsburgh Sleep Quality Index (PSQI)
Time frame: Baseline; Day 4 to Day 28 (final fasting day, depending on participant); and 30 days after the final fasting day
Health-Related Quality of Life - SF-36
Time frame: Baseline; Day 4 to Day 28 (final fasting day, depending on participant); and 30 days after the final fasting day
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 29 Sep 2026.
- Individual participant dataSharing planned: Yes
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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.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Buchinger Wilhelmi prolonged fasting, Online exercise program and Supervised exercise program during prolonged fasting in people with Fasting Conditions and Metabolic Health, run by Universidad de Almeria at 1 site in Spain.
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 4 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: opening soon, as of the sponsor's last update on 29 Sep 2026. 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 Spain. 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 Borja Martínez Téllez, PhD (+34 950215334, borjammt@ual.es), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Handgrip Strength (time frame: Baseline and Day 4 to Day 28 (final fasting day, depending on participant)). 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 29 Sep 2026.