Gestational Diabetes Mellitus (GDM)GDM-HIITNCT07566845

Women With Previous GDM and the Effects of HIIT.

A study testing High-intensity interval training in people with Gestational Diabetes Mellitus (GDM) and Type 2 Diabetes (T2DM), run by Odense University Hospital at 1 site in Denmark.

Enrolling by invitation

Enrolling by invitation. The study team selects and invites participants, usually from an existing group of patients.

Sites and contacts

Official record

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Trial summary

The goal of this clinical trial is to investigate if women with previous gestational diabetes (pGDM) are characterized with unique metabolic and molecular alterations compared to women without pGDM. Furthermore if 8 weeks of high-intensity interval training (HIIT) can improve these alterations. Read more about this study

Who is it for?: Ages 25 to 45 years, women onlyHealthy volunteers can take part
Conditions the study is for: Gestational Diabetes Mellitus (GDM), Type 2 Diabetes (T2DM), High-intensity Interval Training
What is being tested?: High-intensity interval training
Could I receive a placebo?: No, everyone receives an active treatment
How many people: 40 participants
Where: 1 siteDenmark
Study dates: 13 Mar 2026to Nov 2028
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 25 to 45 years
Women only
Healthy volunteers accepted
Adult

Who may be able to join

Age 25-45 years
BMI 20-35 kg/m2
2-8 years since the last pregnancy
No known diabetes or PCOS
No previous bariatric surgery
No known disease

Show all 12Show fewer

Be drug-naive
Have a regular menstrual cycle (23-35 days)
Not be pregnant or planning pregnancy during the study period
Low or moderate level of physical activity must be (max 2 hours of moderate exercise weekly).
All participants should be able to provide informed consent
Women without pGDM must not have known hypertension or first-degree relatives with diabetes.

Who cannot join

Abnormal cardiac stethoscopy, ECG or screening blood tests
Positive plasma GAD-65 antibodies
Positive plasma choriogonadotropine
Undiagnosed T2D based on fasting plasma glucose (≥ 7.0 mmol/mol), plasma HbA1c (≥ 48 mmol/mol), or 2-h plasma glucose during an oral glucose tolerance test (OGTT) (≥ 11.1 mmol/mol)
Dyslipidemia (plasma LDL-cholesterol > 5.0 mmol/l)
In women with pGDM: Undiagnosed severe hypertension (blood pressure > 160/100)
In women without pGDM: Undiagnosed hypertension (blood pressure >140/90 mmHg) or impaired glucose tolerance (fasting plasma glucose at 6.16.9 mmol/l, plasma HbA1c at 42-47 mmol/mol, or a 2-h glucose at 7.8-11.0 mmol/l during an OGTT).

Trial locations and contacts

1 site in 1 country. Contact the study team or a site near you to ask about taking part.

Denmark1 site

Steno Diabetes Center Odense, Odense University Hospital
Odense, Region Syddanmark, 5000

Other trials in Denmark

About this study

Official title: Deep Metabolic and Molecular Phenotyping of Women With Previous Gestational Diabetes Mellitus and the Responses to High-intensity Interval Training.

Women with pGDM have metabolic abnormalities compared with women without pGDM, and that these metabolic abnormalities are explained by unique molecular abnormalities in skeletal muscle and adipose tissue.
Eight weeks of HIIT combining rowing and cycling can markedly improve these metabolic abnormalities in women with pGDM and these improvements are explained by beneficial cellular and molecular changes in skeletal muscle and adipose tissue.

Researchers will compare 20 women with pGDM to 20 glucosetolerant without pGDM, who are matched on age, BMI and times since last pregnancy.

Participants will undergo a screening visit and examinations on two separate days before (day 1 and day 2) and two separate days after (day 3 and day 4) 8-weeks of HIIT, in all cases after an overnight fast (≥ 12 h). Day 1 and day 3 will include assessment of body composition and VO2max. On day 2 and day 4, the insulin sensitivity, substrate metabolism, and β-cell function of the participants will be examined by a Botnia-clamp combined by indirect calorimetry. Skeletal muscle biopsies from m. vastus lateralis and subcutaneous abdominal adipose tissue biopsies are taken in the basal and insulin-stimulated states of each clamp.

Conditions: Gestational Diabetes Mellitus (GDM), Type 2 Diabetes (T2DM), High-intensity Interval Training
Being tested: High-intensity interval training
Keywords: GDM, HIIT, T2DM
Medical subject headings: Diabetes, Gestational, Diabetes Mellitus, Type 2

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

High-intensity interval trainingOther
The training intervention consists of 8-weeks of HIIT combining rowing and cycling on ergometers with two supervised sessions weekly in small groups of up to 10 participants. All HIIT sessions will start with a 10-min warm-up period followed by training blocks of 5 x 1 min high-intensity intervals (100-110% of Wattmax corresponding to ≥ 85% of maximum heart rate (HRmax)) each interspersed by 1 min active or resting recovery. Between the training blocks, the participants will have a 4-min break in which they shift from cycling to rowing or vice versa. The number of training blocks will gradually increase from two to five blocks during the 8-week intervention period with one block being added every second week. Halfway through the HIIT-protocol the workload will be adjusted according to a midway VO2max test. Participants will wear a heart monitor during training sessions.

Study groups in NCT07566845
Study group	Role	What they receive
Women with previous gestational diabetes mellitus	Experimental	Women with previous gestational diabetes mellitus, aged 25-45, who gave birth 2-8 years ago. Receives: Other: High-intensity interval training
Women without previous gestational diabetes	Active comparator	Women without previous gestational diabetes mellitus, aged 25-45, who gave birth 2-8 years ago. Receives: Other: High-intensity interval training

What is being measured

The primary outcome is the main question the study is designed to answer.

β-cell function by OGTT
Will be estimated as the disposition index (DI) by oral glucose tolerance test (OGTT) derived indices of insulin sensitivity and insulin secretion, after a 2-hour OGTT (75g) with measurement of plasma glucose, serum insulin and serum C-peptide at 0, 30 and 120 min.
Measured: At screening visit.
β-cell function by Botnia-clamp
β-cell function adjusted for insulin sensitivity will be determined by calculating the DI as a product of the acute insulin response to glucose (AIRg) and insulin-stimulated glucose infusion rate (GIR).
Measured: At examination day 2 and 4.
Whole body composition (lean body mass and fat mass)
Will be obtained by a dual-energy X-ray absorptiometry (DXA) scanning (Prodigy Advance, GE Healthcare, CHI, US)
Measured: At examination day 1 and 3.
Lean body mass
Will be obtained by a dual-energy X-ray absorptiometry (DXA) scanning (Prodigy Advance, GE Healthcare, CHI, US)
Measured: At examination day 1 and 3.
Fat mass
Will be obtained by a dual-energy X-ray absorptiometry (DXA) scanning (Prodigy Advance, GE Healthcare, CHI, US)
Measured: At examination day 1 and 3.
Cardiorespiratory fitness (maximal oxygen consumptions (VO2-max))
Will be determined by an incremental exercise test on a cycle ergometer (SRM Ergometer System, Jülich, DE) combined with mixed chamber cardiopulmonary exercise analyzer (Oxigraf, Model O2CPX, California, US)
Measured: At examination day 1 and 3.
Insulin sensitivity by Botnia-clamp
Consisting of a hyperinsulinemic-euglycemic clamp (insulin 40mU/min/m2 for 3 h) combined with a 60 min intravenous glucose tolerance test (IVGGT) using a glucose bolus (0.3 kg per kg body weight with a maximum of 25 g glucose).
Measured: At examination day 2 and 4.

Secondary outcomes (11)

Plasma-specific metabolomics by LC- and GC-MS
Liquid chromatography (LC)- and gas chromatography (GS)-based mass spectrometry (MS) will be used to detection, identification, and quantitation of very large numbers of metabolites in the micro- and nano-molar range in body fluids, such as blood.
Measured: At examination day 2 and 4.
Tissue-specific metabolomics by LC- and GC-MS
Liquid chromatography (LC)- and gas chromatography (GS)-based mass spectrometry (MS) will be used to detection, identification, and quantitation of very large numbers of metabolites in the micro- and nano-molar range in body tissues.
Measured: At examination day 2 and 4.
Proteomics
To identify biological processes and signaling networks altered in women with pGDM and changed in response to HIIT, we will apply unbiased mass-spectrometry based proteome analysis of the skeletal muscle and adipose tissue biopsies.
Measured: At examination day 2 and 4.
Phosphoproteomics
To identify biological processes and signaling networks altered in women with pGDM and changed in response to HIIT, we will apply unbiased mass-spectrometry based phosphoproteome analysis of the skeletal muscle and adipose tissue biopsies.
Measured: At examination day 2 and 4.
Transcriptional profiling and gene expression
High-resolution transcriptional profiling of abdominal adipose tissue and skeletal muscle biopsies will be performed using total RNA sequencing with next generation sequencing (TruSeq® Stranded Total RNA Library Prep Gold; Illumina).
Gene expressions are quantified using Targeted quantitative real-time PCR (qRT-PCR) and Western Blotting.
Measured: At examination day 2 and 4.
Mitochondrial respiration
Will be measured on permeabilized muscle fibers, and analyzed by measuring oxygen consumption when adding substrates, uncouplers, and inhibitors to the chambers of a high-resolution oxygraphy.
Measured: At examination day 2 and 4.
Lipid droplets by TEM
The morphology, volume, and localization of lipid droplets in muscle biopsies from the study cohorts will be determined by Transmission Electron Microscopy (TEM).
Measured: At examination day 2 and 4.
Mitochondria by TEM
The morphology, volume, and localization of mitochondria in muscle biopsies from the study cohorts will be determined by Transmission Electron Microscopy (TEM).
Measured: At examination day 2 and 4.
Lipid droplet interaction with mitochondria by TEM
The the physical interaction between lipid droplets and mitochondria in muscle biopsies from the study cohorts will be determined by Transmission Electron Microscopy (TEM).
Measured: At examination day 2 and 4.
Protein abundance
Protein abundance will be studied in skeletal muscle and adipose tissue biopsies by Western blotting procedures.
Measured: At examination day 2 and 4.
Phosphorylation of enzymes
Phosphorylation of enzymes will be studied in skeletal muscle and adipose tissue biopsies by Western blotting procedures.
Measured: At examination day 2 and 4.

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

13 Mar 2026Nov 2028

First posted5 May 2026
Study start13 Mar 2026
Primary completionJan 2028 (estimated)
Study completionNov 2028 (estimated)

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Other trials for Gestational Diabetes Mellitus (GDM)Studies of the same condition, open and under way.
More trials run by Odense University HospitalThe sponsor's other registered studies.
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: Prevention
Allocation: Non-randomised
Intervention model: Parallel groups
Model description: Both groups will undergo same examinations and training-intervention.
Masking: None (open label)
Enrolment: 40 participants (estimated)

IDs, dates and publications

ClinicalTrials.gov ID: NCT07566845
Sponsor's protocol ID: 25/55674
Acronym: GDM-HIIT
Status last verified: Apr 2026
First submitted: 26 Feb 2026
Last updated: 5 May 2026
Results posted: No
Data monitoring committee: Yes
FDA-regulated drug: No
FDA-regulated device: No
Individual data sharing: Yes

Interested in taking part?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

See sites and contacts

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All Gestational Diabetes Mellitus (GDM) trials

Study at a glance

From the registry record, last updated by the sponsor on 5 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: Deep Metabolic and Molecular Phenotyping of Women With Previous Gestational Diabetes Mellitus and the Responses to High-intensity Interval Training.
ClinicalTrials.gov ID: NCT07566845
Acronym / sponsor ID: GDM-HIIT / 25/55674
Conditions: Gestational Diabetes Mellitus (GDM), Type 2 Diabetes (T2DM), High-intensity Interval Training
Keywords: GDM, HIIT, T2DM
Study type: Interventional
Recruitment status: Enrolling by invitation
Enrolment: 40 participants (estimated)
Lead sponsor: Odense University HospitalUniversity, hospital or other
Collaborators: University of Southern Denmark
Study start: 13 Mar 2026 (actual)
Primary completion: Jan 2028 (estimated)
Study completion: Nov 2028 (estimated)
First posted: 5 May 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.

Women with pGDM have metabolic abnormalities compared with women without pGDM, and that these metabolic abnormalities are explained by unique molecular abnormalities in skeletal muscle and adipose tissue.
Eight weeks of HIIT combining rowing and cycling can markedly improve these metabolic abnormalities in women with pGDM and these improvements are explained by beneficial cellular and molecular changes in skeletal muscle and adipose tissue.

Researchers will compare 20 women with pGDM to 20 glucosetolerant without pGDM, who are matched on age, BMI and times since last pregnancy.

Study design

Primary purpose: Prevention
Allocation: Non-randomised
Intervention model: Parallel groups
Masking: None (open label)
Number of arms: 2
Model description: Both groups will undergo same examinations and training-intervention.

Arm	Type	Receives
Women with previous gestational diabetes mellitus	Experimental	Other: High-intensity interval trainingWomen with previous gestational diabetes mellitus, aged 25-45, who gave birth 2-8 years ago.
Women without previous gestational diabetes	Active comparator	Other: High-intensity interval trainingWomen without previous gestational diabetes mellitus, aged 25-45, who gave birth 2-8 years ago.

Who may qualify

Ages: 25 to 45 years
Sex: Female only
Healthy volunteers: Accepted
Age groups: Adult

Key inclusion criteria (12 listed)

Age 25-45 years
BMI 20-35 kg/m2
2-8 years since the last pregnancy
No known diabetes or PCOS
No previous bariatric surgery

Key exclusion criteria (7 listed)

Abnormal cardiac stethoscopy, ECG or screening blood tests
Positive plasma GAD-65 antibodies
Positive plasma choriogonadotropine
Undiagnosed T2D based on fasting plasma glucose (≥ 7.0 mmol/mol), plasma HbA1c (≥ 48 mmol/mol), or 2-h plasma glucose during an oral glucose tolerance test (OGTT) (≥ 11.1 mmol/mol)
Dyslipidemia (plasma LDL-cholesterol > 5.0 mmol/l)

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
High-intensity interval trainingThe training intervention consists of 8-weeks of HIIT combining rowing and cycling on ergometers with two supervised sessions weekly in small groups of up to 10 participants. All HIIT sessions will start with a 10-min warm-up period followed by training blocks of 5 x 1 min high-intensity intervals (100-110% of Wattmax corresponding to ≥ 85% of maximum heart rate (HRmax)) each interspersed by 1 min active or resting recovery. Between the training blocks, the participants will have a 4-min break in which they shift from cycling to rowing or vice versa. The number of training blocks will gradually increase from two to five blocks during the 8-week intervention period with one block being added every second week. Halfway through the HIIT-protocol the workload will be adjusted according to a midway VO2max test. Participants will wear a heart monitor during training sessions.	Other	Women with previous gestational diabetes mellitus, Women without previous gestational diabetes

Primary outcome

β-cell function by OGTT
Time frame: At screening visit.
Will be estimated as the disposition index (DI) by oral glucose tolerance test (OGTT) derived indices of insulin sensitivity and insulin secretion, after a 2-hour OGTT (75g) with measurement of plasma glucose, serum insulin and serum C-peptide at 0, 30 and 120 min.
β-cell function by Botnia-clamp
Time frame: At examination day 2 and 4.
β-cell function adjusted for insulin sensitivity will be determined by calculating the DI as a product of the acute insulin response to glucose (AIRg) and insulin-stimulated glucose infusion rate (GIR).
Whole body composition (lean body mass and fat mass)
Time frame: At examination day 1 and 3.
Will be obtained by a dual-energy X-ray absorptiometry (DXA) scanning (Prodigy Advance, GE Healthcare, CHI, US)
Lean body mass
Time frame: At examination day 1 and 3.
Will be obtained by a dual-energy X-ray absorptiometry (DXA) scanning (Prodigy Advance, GE Healthcare, CHI, US)
Fat mass
Time frame: At examination day 1 and 3.
Will be obtained by a dual-energy X-ray absorptiometry (DXA) scanning (Prodigy Advance, GE Healthcare, CHI, US)
Cardiorespiratory fitness (maximal oxygen consumptions (VO2-max))
Time frame: At examination day 1 and 3.
Will be determined by an incremental exercise test on a cycle ergometer (SRM Ergometer System, Jülich, DE) combined with mixed chamber cardiopulmonary exercise analyzer (Oxigraf, Model O2CPX, California, US)
Insulin sensitivity by Botnia-clamp
Time frame: At examination day 2 and 4.
Consisting of a hyperinsulinemic-euglycemic clamp (insulin 40mU/min/m2 for 3 h) combined with a 60 min intravenous glucose tolerance test (IVGGT) using a glucose bolus (0.3 kg per kg body weight with a maximum of 25 g glucose).

11 secondary outcomes

Plasma-specific metabolomics by LC- and GC-MS
Time frame: At examination day 2 and 4.
Tissue-specific metabolomics by LC- and GC-MS
Time frame: At examination day 2 and 4.
Proteomics
Time frame: At examination day 2 and 4.
Phosphoproteomics
Time frame: At examination day 2 and 4.
Transcriptional profiling and gene expression
Time frame: At examination day 2 and 4.
Mitochondrial respiration
Time frame: At examination day 2 and 4.
Lipid droplets by TEM
Time frame: At examination day 2 and 4.
Mitochondria by TEM
Time frame: At examination day 2 and 4.
Lipid droplet interaction with mitochondria by TEM
Time frame: At examination day 2 and 4.
Protein abundance
Time frame: At examination day 2 and 4.
Phosphorylation of enzymes
Time frame: At examination day 2 and 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 5 May 2026.
Individual participant dataSharing planned: Yes

Related trials for Gestational Diabetes Mellitus (GDM)

Active, not recruiting
Effect of Probiotics on Insulin Sensitivity in Overweight and Obese Pregnancy
Obesity & Overweight, Gestational Diabetes Mellitus (GDM)
Not yet recruitingObservational study
Ultrasound Assessment Of Gastric Volume In Pregnant Women Undergoing Elective Cesarean Section
Gestational Diabetes Mellitus (GDM), Obstetric Anesthesia
Active, not recruitingPhase 2
Effectiveness Study of a Lifestyle Intervention Versus Metformin in Mothers With Recent Gestational Diabetes
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Not yet recruiting
STRONG: SMART Trial
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Not yet recruiting
A Study to Lower Blood Pressure One Year After Childbirth in Women Who Had Preeclampsia
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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.

Kurt Højlund, Prof. Dr. med. principal investigator

Steno Diabetes Center Odense, Odense University Hospital

1 site in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

A study testing High-intensity interval training in people with Gestational Diabetes Mellitus (GDM) and Type 2 Diabetes (T2DM), run by Odense University Hospital at 1 site in Denmark.

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 12 inclusion and 7 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 5 May 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 Denmark. 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?

β-cell function by OGTT (time frame: At screening visit.). The study lists 7 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT07566845.

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 5 May 2026.