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Galactose - the Ideal Carbohydrate Supplement for Exercise in Type 1 Diabetes

Not Applicable
Recruiting
Conditions
Hyperglycemia
Type1diabetes
Hypoglycemia
Interventions
Other: 1-hour cycling
Registration Number
NCT05557227
Lead Sponsor
University of Aarhus
Brief 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. 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.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
14
Inclusion Criteria
  • 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.
Exclusion Criteria
    • 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

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
Dextrose1-hour cycling30 g in 200 ml liquid
Water1-hour cycling200 ml liquid sweetened
Galactose1-hour cycling30 g in 200 ml liquid
Lactose1-hour cycling30 g in 200 ml liquid
Primary Outcome Measures
NameTimeMethod
Time to hypoglycemia Secondary endpoints: Blood glucose variability, volume of intravenous glucose needed to maintain glucose above 5 mmol/l, respiratory exchange ratio.during and 2 hours after the bicycle test

time to blood glucose \< 3.9 mmol/l

Secondary Outcome Measures
NameTimeMethod
Glucose infusionduring and 2 hours after the bicycle test

Volume of intravenous glucose needed to maintain glucose above 5 mmol/l

Time in Rangeprior, during and 2 hours after the bicycle test

Time spend with a blood glucose between 3,9 mmol/l and 10 mmol/l

Blood glucose variabilityduring and 2 hours after the bicycle test

Change in blood glucose (mmol/l) over time

Respiratory exchange ratioprior, during and 2 hours after the bicycle test

RER is measured to to assess carbohydrate and lipid metabolism

Trial Locations

Locations (1)

Steno Diabetes Center Aarhus

🇩🇰

Aarhus, Region Midt, Denmark

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