Effects of Walking and Cycling on Serum Physiological BiomarkersNCT07536659
Evaluation of Serum Autophagic Biomarkers in the Acute Response to Walking and Cycling in Healthy Male Individuals
An observational study of Effects of Walking and Cycling on Serum Physiological Biomarkers, run by Kocaeli University at 2 sites in Turkey (Türkiye).
Trial summary
Physical exercise (walking and cycling) is a potent physiological stimulus that simultaneously alters energy balance, mechanical loading, and metabolic demands in the organism. Autophagy is recognized as a fundamental mechanism in the regulation of acute cellular responses to such stimuli, playing a critical role in… Read more about this study
- Who is it for?
- Ages 18 to 35 years, men onlyHealthy volunteers can take part
- Conditions the study is for
- Effects of Walking and Cycling on Serum Physiological Biomarkers
- What is being tested?
- WALKİNG
- How many people
- 40 participants
- Where
- 2 sitesTurkey (Türkiye)
- Study dates
- 1 Apr 2026to 1 Dec 2026
- Phase
- Observational
- 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 35 years
- Men only
- Healthy volunteers accepted
- Adult
Study population: A total of 20 healthy male volunteers aged between 18 and 35 years, who engage in physical activity at least 2-3 days per week for a minimum of 30 minutes and have no known health problems, will be included in the study. To avoid the effects of previous medical conditions, individuals with acute or chronic injuries in the bilateral/unilateral lower extremities, musculoskeletal disorders, or a history of surgical intervention to the hip and/or knee joints will be excluded from the study. Participants will be instructed to minimize all sports activities 48 hours prior to the assessment days; however, normal daily activities such as walking and stair climbing will be permitted. In addition, participants will be advised to maintain their usual daily routines and to consume the same types of food on the assessment days.
Who may be able to join
- Healthy male volunteers aged 18-35
- Engaging in physical activity at least 2-3 days per week for a minimum of 30 minutes
- Having no known health problems
Who cannot join
- Individuals with acute or chronic injuries in the bilateral/unilateral lower extremities
- Individuals with musculoskeletal disorders in the bilateral/unilateral lower extremities
- Individuals who have undergone surgical intervention to the hip and/or knee joint
- Individuals with cardiopulmonary problems that would prevent them from performing exercise
Trial locations and contacts
2 sites in 1 country. Contact the study team or a site near you to ask about taking part.
Turkey (Türkiye)2 sites
Kocaeli University Faculty of Medicine Hospital
Kocaeli
Sakarya University of Applied Sciences Physiotherapy and Rehabilitation Research Center
Sakarya
About this study
Physical exercise (walking and cycling) is a potent physiological stimulus that simultaneously alters energy balance, mechanical loading, and metabolic demands in the organism. Autophagy is recognized as a fundamental mechanism in the regulation of acute cellular responses to such stimuli, playing a critical role in maintaining cellular homeostasis, removing damaged proteins and organelles, and ensuring metabolic adaptation [1]. Experimental and translational studies have demonstrated that particularly moderate-intensity and controlled mechanical loading can activate autophagic pathways, thereby supporting structural and functional adaptation in muscle, bone, and connective tissues [2-4].
In the current literature, the relationship between autophagy and exercise has largely been evaluated through experimental animal models and a limited number of human studies [5]. Although animal studies have clearly shown that physiological loading such as walking and running increases molecular signals associated with autophagy, the direct assessment of autophagy at the tissue level in humans is limited due to ethical and feasibility concerns, as it requires invasive methods (e.g., muscle biopsy) [3]. Therefore, recent human studies have increasingly focused on indirect evaluation of autophagy through peripheral blood mononuclear cells and circulating biomarkers [6].
Read more
Indeed, recent human studies have reported that proteins associated with autophagy may exhibit changes in peripheral blood cells or circulation in response to acute exercise, and that this response may vary depending on the type, intensity, and mechanical characteristics of the exercise [6]. These findings suggest that autophagy is not merely a tissue-specific process but can also be monitored at the systemic level as part of physiological adaptation [7]. However, there is a limited number of human studies that comparatively investigate the acute effects of different exercise modalities with distinct mechanical loading profiles (such as walking and cycling) on serum biomarkers related to autophagy.
In this context, the present project aims to evaluate the acute effects of two common aerobic exercise modalities with different mechanical loading characteristics-walking and cycling-on serum biomarkers associated with autophagy in healthy male individuals. In this study, Beclin-1, LC3, and ATG3 levels will be considered not as direct indicators of autophagic flux in tissues, but as circulating biomarkers associated with the initiation and maintenance of autophagy. By examining changes in the serum levels of these proteins following acute exercise, it is aimed to obtain indirect yet biologically meaningful data regarding exercise-induced cellular adaptation mechanisms without the need for invasive procedures.
In conclusion, this study aims to contribute to an important gap in the current literature by safely and ethically demonstrating the acute physiological responses related to autophagy in humans across exercise modalities with different mechanical characteristics, thereby enhancing our understanding of the exercise-autophagy relationship.
Read the detailed description
Aim of the Study The aim of this study is to evaluate the acute effects of walking and cycling on serum physiological biomarkers associated with autophagy (Beclin-1, LC3, and ATG3).
Previous studies have mostly investigated changes in biomarker levels following a single type of exercise. Therefore, the effects of exercise regimens with different mechanical loading characteristics on circulating autophagy-related biomarkers are not sufficiently understood.
This study aims to comparatively examine the acute effects of two different exercise regimens-walking and cycling-on serum biomarkers associated with autophagy.
Hypotheses H0: There is no change in serum Beclin-1, LC3, and ATG3 levels following walking and cycling.
H1: There is a change in serum Beclin-1, LC3, and ATG3 levels following walking and cycling.
Inclusion Criteria Healthy male volunteers aged 18-35 years Individuals who engage in physical activity at least 30 minutes per day, 2-3 days per week Individuals without any known health problems
Exclusion Criteria Individuals with acute or chronic injuries in the unilateral/bilateral lower extremities Individuals with musculoskeletal disorders in the unilateral/bilateral lower extremities Individuals who have undergone surgical intervention involving the hip and/or knee joints Individuals with cardiopulmonary conditions that would prevent them from performing exercise
Research Method The study will commence after obtaining ethical approval. A total of 20 healthy male volunteers aged between 18-35 years, who are physically active (at least 30 minutes, 2-3 times per week) and have no known health problems, will be included.
To avoid the effects of prior medical conditions, individuals with acute or chronic lower extremity injuries, musculoskeletal disorders, or a history of hip and/or knee surgery will be excluded.
Participants will be instructed to minimize all sports activities 48 hours prior to the assessment sessions; however, normal daily activities such as walking and stair climbing will be permitted. They will also be advised to maintain their usual daily routines and consume the same types of food on evaluation days.
Body weight, body mass index (BMI), age, and heart rate will be recorded before and after the exercise sessions. Exercise intensity will be determined based on heart rate (HR), calculated as:
Lower limit: HR = (220 - age) × 50% Upper limit: HR = (220 - age) × 85% [8]
Heart rate will be measured by placing the index and middle fingers on the carotid artery for 15 seconds, and the value will be multiplied by four. The 30-minute exercise protocol will consist of:
First 5 minutes: lower HR limit Next 20 minutes: upper HR limit Final 5 minutes: lower HR limit Anthropometric Measurements Body weight will be measured using a digital scale with 0.1 kg sensitivity, and height will be measured using a digital stadiometer. Participants will be barefoot, wearing only shorts, with knees fully extended, heels together, and standing upright.
Exercise Protocol
Data collection will be conducted in two separate 30-minute exercise sessions, spaced one week apart:
Session 1: Participants will walk on a treadmill at the target heart rate for 30 minutes.
Session 2: One week later, participants will perform 30 minutes of cycling on a bicycle ergometer at a similar heart rate.
All procedures, except for the type of exercise, will be identical between sessions. Participants will attend the laboratory at the same time of day to avoid diurnal variations. A minimum one-week rest period will be provided between sessions to minimize carryover effects.
Blood Sampling Procedure A permanent venous catheter will be inserted into the cubital fossa of either arm. To minimize the effects of prior physical activity, participants will rest in a supine position for 30 minutes upon arrival.
Blood samples will be collected at the following time points:
After the 30-minute rest period (baseline) Immediately after the 30-minute exercise session 30 minutes post-exercise 60 minutes post-exercise The same procedure will be repeated in the second session (cycling). Collection and Analysis of Blood Samples Peripheral blood samples will be collected into gel-containing biochemistry tubes. Approximately 2-2.5 mL of blood (about half a standard tube) will be collected each time.
After clotting at room temperature (20-30 minutes), samples will be centrifuged at 3500 rpm for 10 minutes at +4°C to obtain serum. Serum samples will be stored at -80°C until analysis.
Protein Measurement Serum protein levels will be measured using ELISA kits according to the manufacturer's instructions. A Multiskan Go spectrophotometer (Thermo Fisher Scientific, Finland) will be used. Measurements will be analyzed using Thermo Scientific SkanIt software, and protein concentrations will be determined by comparison with standard curves.
Analyzed Proteins Beclin-1 LC3 ATG3
- Being tested
- WALKİNG
- Keywords
- Biomarkers, walking, cycling
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
WALKİNGOther
Data collection will be carried out in two separate 30-minute exercise sessions, scheduled one week apart. In the first session, participants will perform 30 minutes of walking on a treadmill at a predetermined target heart rate. In the second session, conducted one week later, participants will cycle on a bicycle ergometer for 30 minutes at a similar target heart rate. Apart from the 30-minute exercise modality, all other procedures will be identical in both data collection sessions. To avoid diurnal variations, participants will be asked to attend the laboratory at the same time of day for each session. A minimum one-week rest period will be provided between sessions to minimize potential carryover effects.
Upon arrival at the laboratory, an indwelling venous catheter will be inserted into the cubital fossa of either the right or left arm of the participant. To minimize the potential effects of prior physical activity on biomarker concentrations, participants will rest in a supine po
| Study group | Role | What they receive |
|---|---|---|
| walking | cycling Receives: Other: WALKİNG |
What is being measured
The primary outcome is the main question the study is designed to answer.
Beclin-1
AUTOPHAGY
Measured: 1 WEEK
LC3
AUTOPHAGY-
Measured: 1 WEEK
ATG3
AUTOPHAGY
Measured: 1 WEEK
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted17 Apr 2026
- Study start1 Apr 2026
- Primary completion30 Oct 2026 (estimated)
- Study completion1 Dec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Effects of Walking and Cycling on Serum Physiological BiomarkersStudies 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
- Observational
- Observational model
- Case crossover
- Time perspective
- Cross-sectional
- Enrolment
- 40 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Kocaeli University
- Sponsor type
- University, hospital or other
- Collaborators
- Sakarya Applied Sciences University
- Responsible party
- Principal investigator, Oguzhan Bahadir DEMIR, Kocaeli University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07536659
- Sponsor's protocol ID
- GOKAEK- 2026/192
- Status last verified
- Apr 2026
- First submitted
- 11 Apr 2026
- Last updated
- 21 Apr 2026
- Results posted
- 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 21 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Evaluation of Serum Autophagic Biomarkers in the Acute Response to Walking and Cycling in Healthy Male Individuals
- ClinicalTrials.gov ID
- NCT07536659
- Acronym / sponsor ID
- GOKAEK- 2026/192
- Keywords
- Biomarkers, walking, cycling
- Study type
- Observational
- Recruitment status
- Enrolling by invitation
- Enrolment
- 40 participants (estimated)
- Lead sponsor
- Kocaeli UniversityUniversity, hospital or other
- Collaborators
- Sakarya Applied Sciences University
- Study start
- 1 Apr 2026 (actual)
- Primary completion
- 30 Oct 2026 (estimated)
- Study completion
- 1 Dec 2026 (estimated)
- First posted
- 17 Apr 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.
Physical exercise (walking and cycling) is a potent physiological stimulus that simultaneously alters energy balance, mechanical loading, and metabolic demands in the organism. Autophagy is recognized as a fundamental mechanism in the regulation of acute cellular responses to such stimuli, playing a critical role in maintaining cellular homeostasis, removing damaged proteins and organelles, and ensuring metabolic adaptation [1]. Experimental and translational studies have demonstrated that particularly moderate-intensity and controlled mechanical loading can activate autophagic pathways, thereby supporting structural and functional adaptation in muscle, bone, and connective tissues [2-4].
In the current literature, the relationship between autophagy and exercise has largely been evaluated through experimental animal models and a limited number of human studies [5]. Although animal studies have clearly shown that physiological loading such as walking and running increases molecular signals associated with autophagy, the direct assessment of autophagy at the tissue level in humans is limited due to ethical and feasibility concerns, as it requires invasive methods (e.g., muscle biopsy) [3]. Therefore, recent human studies have increasingly focused on indirect evaluation of autophagy through peripheral blood mononuclear cells and circulating biomarkers [6].
Indeed, recent human studies have reported that proteins associated with autophagy may exhibit changes in peripheral blood cells or circulation in response to acute exercise, and that this response may vary depending on the type, intensity, and mechanical characteristics of the exercise [6]. These findings suggest that autophagy is not merely a tissue-specific process but can also be monitored at the systemic level as part of physiological adaptation [7]. However, there is a limited number of human studies that comparatively investigate the acute effects of different exercise modalities with distinct mechanical loading profiles (such as walking and cycling) on serum biomarkers related to autophagy.
In this context, the present project aims to evaluate the acute effects of two common aerobic exercise modalities with different mechanical loading characteristics-walking and cycling-on serum biomarkers associated with autophagy in healthy male individuals. In this study, Beclin-1, LC3, and ATG3 levels will be considered not as direct indicators of autophagic flux in tissues, but as circulating biomarkers associated with the initiation and maintenance of autophagy. By examining changes in the serum levels of these proteins following acute exercise, it is aimed to obtain indirect yet biologically meaningful data regarding exercise-induced cellular adaptation mechanisms without the need for invasive procedures.
In conclusion, this study aims to contribute to an important gap in the current literature by safely and ethically demonstrating the acute physiological responses related to autophagy in humans across exercise modalities with different mechanical characteristics, thereby enhancing our understanding of the exercise-autophagy relationship.
Detailed description
Aim of the Study The aim of this study is to evaluate the acute effects of walking and cycling on serum physiological biomarkers associated with autophagy (Beclin-1, LC3, and ATG3).
Previous studies have mostly investigated changes in biomarker levels following a single type of exercise. Therefore, the effects of exercise regimens with different mechanical loading characteristics on circulating autophagy-related biomarkers are not sufficiently understood.
This study aims to comparatively examine the acute effects of two different exercise regimens-walking and cycling-on serum biomarkers associated with autophagy.
Hypotheses H0: There is no change in serum Beclin-1, LC3, and ATG3 levels following walking and cycling.
H1: There is a change in serum Beclin-1, LC3, and ATG3 levels following walking and cycling.
Inclusion Criteria Healthy male volunteers aged 18-35 years Individuals who engage in physical activity at least 30 minutes per day, 2-3 days per week Individuals without any known health problems
Exclusion Criteria Individuals with acute or chronic injuries in the unilateral/bilateral lower extremities Individuals with musculoskeletal disorders in the unilateral/bilateral lower extremities Individuals who have undergone surgical intervention involving the hip and/or knee joints Individuals with cardiopulmonary conditions that would prevent them from performing exercise
Research Method The study will commence after obtaining ethical approval. A total of 20 healthy male volunteers aged between 18-35 years, who are physically active (at least 30 minutes, 2-3 times per week) and have no known health problems, will be included.
To avoid the effects of prior medical conditions, individuals with acute or chronic lower extremity injuries, musculoskeletal disorders, or a history of hip and/or knee surgery will be excluded.
Participants will be instructed to minimize all sports activities 48 hours prior to the assessment sessions; however, normal daily activities such as walking and stair climbing will be permitted. They will also be advised to maintain their usual daily routines and consume the same types of food on evaluation days.
Body weight, body mass index (BMI), age, and heart rate will be recorded before and after the exercise sessions. Exercise intensity will be determined based on heart rate (HR), calculated as:
Lower limit: HR = (220 - age) × 50% Upper limit: HR = (220 - age) × 85% [8]
Heart rate will be measured by placing the index and middle fingers on the carotid artery for 15 seconds, and the value will be multiplied by four. The 30-minute exercise protocol will consist of:
First 5 minutes: lower HR limit Next 20 minutes: upper HR limit Final 5 minutes: lower HR limit Anthropometric Measurements Body weight will be measured using a digital scale with 0.1 kg sensitivity, and height will be measured using a digital stadiometer. Participants will be barefoot, wearing only shorts, with knees fully extended, heels together, and standing upright.
Exercise Protocol
Data collection will be conducted in two separate 30-minute exercise sessions, spaced one week apart:
Session 1: Participants will walk on a treadmill at the target heart rate for 30 minutes.
Session 2: One week later, participants will perform 30 minutes of cycling on a bicycle ergometer at a similar heart rate.
All procedures, except for the type of exercise, will be identical between sessions. Participants will attend the laboratory at the same time of day to avoid diurnal variations. A minimum one-week rest period will be provided between sessions to minimize carryover effects.
Blood Sampling Procedure A permanent venous catheter will be inserted into the cubital fossa of either arm. To minimize the effects of prior physical activity, participants will rest in a supine position for 30 minutes upon arrival.
Blood samples will be collected at the following time points:
After the 30-minute rest period (baseline) Immediately after the 30-minute exercise session 30 minutes post-exercise 60 minutes post-exercise The same procedure will be repeated in the second session (cycling). Collection and Analysis of Blood Samples Peripheral blood samples will be collected into gel-containing biochemistry tubes. Approximately 2-2.5 mL of blood (about half a standard tube) will be collected each time.
After clotting at room temperature (20-30 minutes), samples will be centrifuged at 3500 rpm for 10 minutes at +4°C to obtain serum. Serum samples will be stored at -80°C until analysis.
Protein Measurement Serum protein levels will be measured using ELISA kits according to the manufacturer's instructions. A Multiskan Go spectrophotometer (Thermo Fisher Scientific, Finland) will be used. Measurements will be analyzed using Thermo Scientific SkanIt software, and protein concentrations will be determined by comparison with standard curves.
Analyzed Proteins Beclin-1 LC3 ATG3
Study design
- Observational model
- Case crossover
- Time perspective
- Cross-sectional
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| walking | – | Other: WALKİNGcycling |
Who may qualify
- Ages
- 18 to 35 years
- Sex
- Male only
- Healthy volunteers
- Accepted
- Age groups
- Adult
- Study population
- A total of 20 healthy male volunteers aged between 18 and 35 years, who engage in physical activity at least 2-3 days per week for a minimum of 30 minutes and have no known health problems, will be included in the study. To avoid the effects of previous medical conditions, individuals with acute or chronic injuries in the bilateral/unilateral lower extremities, musculoskeletal disorders, or a history of surgical intervention to the hip and/or knee joints will be excluded from the study. Participants will be instructed to minimize all sports activities 48 hours prior to the assessment days; however, normal daily activities such as walking and stair climbing will be permitted. In addition, participants will be advised to maintain their usual daily routines and to consume the same types of food on the assessment days.
Key inclusion criteria (3 listed)
- Healthy male volunteers aged 18-35
- Engaging in physical activity at least 2-3 days per week for a minimum of 30 minutes
- Having no known health problems
Key exclusion criteria (4 listed)
- Individuals with acute or chronic injuries in the bilateral/unilateral lower extremities
- Individuals with musculoskeletal disorders in the bilateral/unilateral lower extremities
- Individuals who have undergone surgical intervention to the hip and/or knee joint
- Individuals with cardiopulmonary problems that would prevent them from performing exercise
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 |
|---|---|---|
| WALKİNGData collection will be carried out in two separate 30-minute exercise sessions, scheduled one week apart. In the first session, participants will perform 30 minutes of walking on a treadmill at a predetermined target heart rate. In the second session, conducted one week later, participants will cycle on a bicycle ergometer for 30 minutes at a similar target heart rate. Apart from the 30-minute exercise modality, all other procedures will be identical in both data collection sessions. To avoid diurnal variations, participants will be asked to attend the laboratory at the same time of day for each session. A minimum one-week rest period will be provided between sessions to minimize potential carryover effects. Upon arrival at the laboratory, an indwelling venous catheter will be inserted into the cubital fossa of either the right or left arm of the participant. To minimize the potential effects of prior physical activity on biomarker concentrations, participants will rest in a supine po | Other | walking |
Primary outcome
Beclin-1
Time frame: 1 WEEK
AUTOPHAGY
LC3
Time frame: 1 WEEK
AUTOPHAGY-
ATG3
Time frame: 1 WEEK
AUTOPHAGY
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 21 Apr 2026.
- Individual participant dataSharing planned: No
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.
The record lists no contact. Use the official record to reach the sponsor.
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Effects of Walking and Cycling on Serum Physiological Biomarkers, run by Kocaeli University at 2 sites in Turkey (Türkiye).
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 3 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: enrolling by invitation, as of the sponsor's last update on 21 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in Turkey (Türkiye). 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?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Beclin-1 (time frame: 1 WEEK). The study lists 3 primary outcomes in all. 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 21 Apr 2026.