Type1diabetesNCT05557227
Galactose - the Ideal Carbohydrate Supplement for Exercise in Type 1 Diabetes
A study testing 1-hour cycling in people with Type1diabetes and Hypoglycemia, run by University of Aarhus at 1 site in Denmark.
Trial summary
In this study, 14 subjects with type 1 diabetes are studied in a randomized crossover study in which the subjects cycle at a fixed intensity at 60% of their maximum oxygen capacity (VO2 max) for 1 hour. Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Type1diabetes, Hypoglycemia, Hyperglycemia
- What is being tested?
- 1-hour cycling
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 14 participants
- Where
- 1 siteDenmark
- Study dates
- 15 Dec 2022to 1 Jun 2024
- Phase
- Interventional
- Are there results?
- None posted in the registry
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 65 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- type 1 diabetes for at least 2 years
- age between 18 and 65 years
- HbA1c less than 70 mmol/mol
- Physically active (at least 150 minutes of moderate-to-vigorous intensity activity weekly)
- Insulin pen and pump treatment
- Men and women are eligible, but women will have to perform study days in the mid-cycle phase of the menstrual cycle.
Who cannot join
- - Diabetic nephropathy, neuropathy, and proliferative retinopathy
- Hypoglycemia unawareness
- Lactose intolerance
- Heart disease and other conditions which may be negatively affected by the VO2 max test and 1-hour cycling on study days
Trial locations and contacts
1 site in 1 country.
About this study
In this study, 14 subjects with type 1 diabetes are studied in a randomized crossover study in which the subjects cycle at a fixed intensity at 60% of their maximum oxygen capacity (VO2 max) for 1 hour. Thirty minutes before each cycling test, participants consume a 200 ml beverage, consisting of either: 1) dextrose (20 g), 2) galactose (20 g), 3) lactose (20 g) or 4) water (sweetened). If blood sugar drops below 3.9 mmol/l, glucose infusion is given and blood sugar is kept just above 5 mmol/L.
The trial days take place at least 4 days apart.
Read the detailed description
On study days, a catheter is placed in two antecubital veins for regular blood sampling and for glucose infusion (if needed). The participant will rest in a bed, when not performing the 1-hour bicycle ergometer test.
Thirty minutes before the leg-cycle ergometer test, the participants consume a 300 ml beverage containing either: 1) dextrose (20 g), 2) galactose (20 g) 3) lactose (20 g) or 4) water (sweetened). At t=0, the ergometer test is started and continued for 1 hour (fixed intensity cycling at 60% of VO2-max). If blood glucose drops below 3.9 mmol/l, glucose infusion (5 % glucose) will be administered, and blood glucose is kept just above 5 mmol/l and infused volume is registered.
Blood samples are collected at t= -40, 0, 30, 60, 90, 120 for measurement of plasma lactate, non-esterified fatty acids (NEFA), plasma triglyceride and hormonal concentrations (epinephrine, norepinephrine, cortisol, and glucagon). Plasma blood glucose measurements are performed at t = -40 and every 10-15 minutes until the end of the study day.
Respiratory exchange ratio is measured by indirect calorimetry (collection of respiratory gasses VO2 and VCO2) pre-exercise, at the end of the exercise bout, and 30 minutes post-exercise. Protein oxidation rate is estimated from urinary urea excretion, and net lipid and glucose oxidation rates are calculated from indirect calorimetry measurements with correction for protein oxidation. Therefor a urine sample will also be collected at the end of the study day.
The bicycle ergometer test is discontinued after 1 hour of bicycling and the participant is observed until 2 hour post exercise where the study day is ended.
- Conditions
- Type1diabetes, Hypoglycemia, Hyperglycemia
- Being tested
- 1-hour cycling
- Medical subject headings
- Hypoglycemia, Hyperglycemia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
1-hour cyclingOther
60 % VO2 max
| Study group | Role | What they receive |
|---|---|---|
| Galactose | Experimental | 30 g in 200 ml liquid Receives: Other: 1-hour cycling |
| Lactose | Experimental | 30 g in 200 ml liquid Receives: Other: 1-hour cycling |
| Dextrose | Experimental | 30 g in 200 ml liquid Receives: Other: 1-hour cycling |
| Water | Experimental | 200 ml liquid sweetened Receives: Other: 1-hour cycling |
What is being measured
The primary outcome is the main question the study is designed to answer.
Time to hypoglycemia Secondary endpoints: Blood glucose variability, volume of intravenous glucose needed to maintain glucose above 5 mmol/l, respiratory exchange ratio.
time to blood glucose < 3.9 mmol/l
Measured: during and 2 hours after the bicycle test
Secondary outcomes (4)
Blood glucose variability
Change in blood glucose (mmol/l) over time
Measured: during and 2 hours after the bicycle test
Glucose infusion
Volume of intravenous glucose needed to maintain glucose above 5 mmol/l
Measured: during and 2 hours after the bicycle test
Respiratory exchange ratio
RER is measured to to assess carbohydrate and lipid metabolism
Measured: prior, during and 2 hours after the bicycle test
Time in Range
Time spend with a blood glucose between 3,9 mmol/l and 10 mmol/l
Measured: prior, during and 2 hours after the bicycle test
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 Sep 2022
- Study start15 Dec 2022
- Primary completion1 Jan 2024
- Study completion1 Jun 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Type1diabetesStudies of the same condition, open and under way.
- More trials run by University of AarhusThe 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
- Randomised
- Intervention model
- Crossover
- Model description
- The study is a single-blinded, randomized crossover study, consisting of 4 study days of 1-hour fixed intensity cycling, after consumption of either galactose, lactose, glucose or water.
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 14 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Aarhus
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Rakel Johansen, University of Aarhus
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05557227
- Sponsor's protocol ID
- 93696
- Status last verified
- Dec 2022
- First submitted
- 15 Aug 2022
- Last updated
- 29 Jun 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Schmidt KR, Johansen RF, Riis SB, Larsen MS, Stovring H, Wallis GA, Rowlands D, Gormsen LC, Sondergaard E. Pre-Exercise Galactose or Lactose Reduces Glycaemic Excursions During Exercise in Adults With Type 1 Diabetes: A Randomised, Double-Blind, Crossover Trial. Diabetes Obes Metab. 2026 Sep;28(9):7825-7833. doi: 10.1111/dom.70958. Epub 2026 Jun 9.
PubMed 42264961
Study at a glance
From the registry record, last updated by the sponsor on 29 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Galactose - the Ideal Carbohydrate Supplement for Exercise in Type 1 Diabetes
- ClinicalTrials.gov ID
- NCT05557227
- Acronym / sponsor ID
- 93696
- Conditions
- Type1diabetes, Hypoglycemia, Hyperglycemia
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 14 participants (actual)
- Lead sponsor
- University of AarhusUniversity, hospital or other
- Study start
- 15 Dec 2022 (actual)
- Primary completion
- 1 Jan 2024 (actual)
- Study completion
- 1 Jun 2024 (actual)
- First posted
- 27 Sep 2022 (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.
In this study, 14 subjects with type 1 diabetes are studied in a randomized crossover study in which the subjects cycle at a fixed intensity at 60% of their maximum oxygen capacity (VO2 max) for 1 hour. Thirty minutes before each cycling test, participants consume a 200 ml beverage, consisting of either: 1) dextrose (20 g), 2) galactose (20 g), 3) lactose (20 g) or 4) water (sweetened). If blood sugar drops below 3.9 mmol/l, glucose infusion is given and blood sugar is kept just above 5 mmol/L.
The trial days take place at least 4 days apart.
Detailed description
On study days, a catheter is placed in two antecubital veins for regular blood sampling and for glucose infusion (if needed). The participant will rest in a bed, when not performing the 1-hour bicycle ergometer test.
Thirty minutes before the leg-cycle ergometer test, the participants consume a 300 ml beverage containing either: 1) dextrose (20 g), 2) galactose (20 g) 3) lactose (20 g) or 4) water (sweetened). At t=0, the ergometer test is started and continued for 1 hour (fixed intensity cycling at 60% of VO2-max). If blood glucose drops below 3.9 mmol/l, glucose infusion (5 % glucose) will be administered, and blood glucose is kept just above 5 mmol/l and infused volume is registered.
Blood samples are collected at t= -40, 0, 30, 60, 90, 120 for measurement of plasma lactate, non-esterified fatty acids (NEFA), plasma triglyceride and hormonal concentrations (epinephrine, norepinephrine, cortisol, and glucagon). Plasma blood glucose measurements are performed at t = -40 and every 10-15 minutes until the end of the study day.
Respiratory exchange ratio is measured by indirect calorimetry (collection of respiratory gasses VO2 and VCO2) pre-exercise, at the end of the exercise bout, and 30 minutes post-exercise. Protein oxidation rate is estimated from urinary urea excretion, and net lipid and glucose oxidation rates are calculated from indirect calorimetry measurements with correction for protein oxidation. Therefor a urine sample will also be collected at the end of the study day.
The bicycle ergometer test is discontinued after 1 hour of bicycling and the participant is observed until 2 hour post exercise where the study day is ended.
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Single blind (participant)
- Number of arms
- 4
- Model description
- The study is a single-blinded, randomized crossover study, consisting of 4 study days of 1-hour fixed intensity cycling, after consumption of either galactose, lactose, glucose or water.
| Arm | Type | Receives |
|---|---|---|
| Galactose | Experimental | Other: 1-hour cycling30 g in 200 ml liquid |
| Lactose | Experimental | Other: 1-hour cycling30 g in 200 ml liquid |
| Dextrose | Experimental | Other: 1-hour cycling30 g in 200 ml liquid |
| Water | Experimental | Other: 1-hour cycling200 ml liquid sweetened |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- type 1 diabetes for at least 2 years
- age between 18 and 65 years
- HbA1c less than 70 mmol/mol
- Physically active (at least 150 minutes of moderate-to-vigorous intensity activity weekly)
- Insulin pen and pump treatment
Key exclusion criteria (4 listed)
- - Diabetic nephropathy, neuropathy, and proliferative retinopathy
- Hypoglycemia unawareness
- Lactose intolerance
- Heart disease and other conditions which may be negatively affected by the VO2 max test and 1-hour cycling on study days
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 |
|---|---|---|
| 1-hour cycling60 % VO2 max | Other | Dextrose, Galactose, Lactose, Water |
Primary outcome
Time to hypoglycemia Secondary endpoints: Blood glucose variability, volume of intravenous glucose needed to maintain glucose above 5 mmol/l, respiratory exchange ratio.
Time frame: during and 2 hours after the bicycle test
time to blood glucose < 3.9 mmol/l
4 secondary outcomes
Blood glucose variability
Time frame: during and 2 hours after the bicycle test
Glucose infusion
Time frame: during and 2 hours after the bicycle test
Respiratory exchange ratio
Time frame: prior, during and 2 hours after the bicycle test
Time in Range
Time frame: prior, during and 2 hours after the bicycle test
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 Jun 2026.
- Derived from this study: PubMed 42264961Schmidt KR, Johansen RF, Riis SB, Larsen MS, Stovring H, Wallis GA, Rowlands D, Gormsen LC, Sondergaard E. Pre-Exercise Galactose or Lactose Reduces Glycaemic Excursions During Exercise in Adults With Type 1 Diabetes: A Randomised, Double-Blind, Crossover Trial. Diabetes Obes Metab. 2026 Sep;28(9):7825-7833. doi: 10.1111/dom.70958. Epub 2026 Jun 9.
- 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. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing 1-hour cycling in people with Type1diabetes and Hypoglycemia, run by University of Aarhus 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 6 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: finished, as of the sponsor's last update on 29 Jun 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?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
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?
Time to hypoglycemia Secondary endpoints: Blood glucose variability, volume of intravenous glucose needed to maintain glucose above 5 mmol/l, respiratory exchange ratio. (time frame: during and 2 hours after the bicycle test). 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 NCT05557227, which also lists 1 linked publication.
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 Jun 2026.