Effects of Frequency and Duration of Exercise in People With Type 1 Diabetes A Randomized Crossover Study

Effects of Frequency and Duration of Exercise in People With Type 1 Diabetes A Randomized Crossover Study

Effects of Frequency and Duration of Exercise in People With Type 1 Diabetes - A Randomized Crossover Study

According to the Standards of Medical Care in Diabetes by the American Diabetes Association, people with diabetes should aim for 30 minutes of moderate-to-vigorous intensity aerobic exercise at least 5 days a week or a total of 150 minutes per week and doing some type of strength training at least 2 times per week in addition to aerobic activity. However, the effects of different forms and intervals of exercise on glycemic control are not well established. Exercise increases the risk of hypoglycemia both during and several hours after exercise. There are several strategies to avoid hypoglycemia during exercise. The most common strategy is to reduce insulin and to take carbohydrates before the exercise starts. Short-acting insulin analogs have a duration of approximately four hours, thus reductions need to be planned and done well in advance before the exercise starts. Since different types of exercise (aerobic, strength training or high intensity training) affect blood glucose in different ways and most exercise sessions include a combination of the types, these strategies are often associated with difficulties in obtaining stable blood glucose. The American Diabetes Association guidelines do not explicitly recommend a daily workout routine but outline recommendations for weekly amounts of exercise as there is currently insufficient evidence on the ideal timing, frequency and duration of exercise for preventing hypoglycemia. Hypothesis: in people with type 1 diabetes, time in hypoglycemia can be reduced if exercise is performed daily over five consecutive days compared to the same total amount of exercise performed at 2 days with at least 2 days interval. Aim: to evaluate the impact of the same total amount of exercise split into either five consecutive sessions or two sessions with at least 2 days in between on percentage of time spent in hypoglycemia and other glycemic parameters in people with type 1 diabetes.

The participants will go through two interventions: Exercise one session per day for five consecutive days and Exercise one session per day for two days within five days. The exercise session will start with anaerobic (push-ups, back-curls, sit-ups, triceps-dips and jumps) exercise followed by aerobic exercise (moderate intensity of running, walking or cycling). Between the two intervention periods, there will be a wash-out period. Intervention: 'Exercise one session per day for five consecutive days'. Duration per session: Anaerobic: 4 min, Aerobic: 30 min. Sessions per intervention period: Five. Total duration per intervention period: Anaerobic: 20 min. Aerobic: 150 min. Total: 170 min Intervention:Exercise one session per day for two days within five days. Duration per session: Anaerobe: 10 min, Aerobe: 75 min. Sessions per intervention period: 2. Total duration per intervention period: Anaerob: 20 min Aerobe: 150 min Total: 170 min

An open-labelled randomized controlled crossover study will be performed. The participants will go through the following elements: Screening day Run-in period Intervention period Wash-out period Intervention period

Period 1: 5 exercise sessions on 5 consecutive days (4 min anaerobic exercise and 30 min aerobic exercise per session) Period 2: 2 exercise sessions within a 5-day period (10 min anaerobic exercise and 75 min aerobic exercise per session)

Period 1: 2 exercise sessions within a 5-day period (10 min anaerobic exercise and 75 min aerobic exercise per session) Period 2: 5 exercise sessions on 5 consecutive days (4 min anaerobic exercise and 30 min aerobic exercise per session)

Level 1 (alert): CGM or SMBG value of 3.0-3.9 mmol/l with or without symptoms. Level 2 (clinical): CGM or SMBG value of < 3.0 mmol/l with or without symptoms. Outcome is compared between the two intervention periods in a per protocol analysis (PP) and intention-to-treat analysis (ITT)

Level 1 (alert): CGM or SMBG value of 3.0-3.9 mmol/l with or without symptoms. Level 2 (clinical): CGM or SMBG value of < 3.0 mmol/l with or without symptoms. Outcome is also compared between the two intervention periods in a per protocol analysis (PP) and intention-to-treat analysis (ITT)

Level 1 (alert): CGM or SMBG value of 3.0-3.9 mmol/l with or without symptoms. Level 2 (clinical): CGM or SMBG value of < 3.0 mmol/l with or without symptoms. Outcome is also compared between the two intervention periods in a per protocol analysis (PP) and intention-to-treat analysis (ITT)

Level 1 (alert): CGM or SMBG value of 3.0-3.9 mmol/l with or without symptoms. Level 2 (clinical): CGM or SMBG value of < 3.0 mmol/l with or without symptoms. Outcome is also compared between the two intervention periods in a per protocol analysis (PP) and intention-to-treat analysis (ITT)

Level 1 (alert): CGM or SMBG value of 3.0-3.9 mmol/l with or without symptoms. Level 2 (clinical): CGM or SMBG value of < 3.0 mmol/l with or without symptoms. Outcome is compared between the two intervention periods in a per protocol analysis (PP) and intention-to-treat analysis (ITT)

Level 1 (alert): CGM or SMBG value of 3.0-3.9 mmol/l with or without symptoms. Level 2 (clinical): CGM or SMBG value of < 3.0 mmol/l with or without symptoms. Outcome is compared between the two intervention periods in a per protocol analysis (PP) and intention-to-treat analysis (ITT)

The time the participant has recorded start and end of exercise session during study day 1 to study day 6

Exercise time: The time the participant has recorded start and end of exercise session during study day 1 study day 6

Exercise time: The time the participant has recorded start and end of exercise session during study day 1 - study day 6

Exercise time: The time the participant has recorded start and end of exercise session during study day 1 -study day 6

Exercise time: The time the participant has recorded start and end of exercise session during study day 1-study day 6

Exercise time: The time the participant has recorded start and end of exercise session during study day 1-study day 6

Percentage of time in hyperglycemia (>10 mmol/l) during all the predefined time blocks. Per protocol analysis and intention-to-treat analysis

Glycemic variability measured as standard deviation (SD), coefficient of variation (CV) and low and high blood glucose index (LBGI/HBGI) during all the predefined time blocks in the intervention period

Glycemic variability measured as standard deviation (SD), coefficient of variation (CV) and low and high blood glucose index (LBGI/HBGI) during all the predefined time blocks in the intervention period

Glycemic variability measured as standard deviation (SD), coefficient of variation (CV) and low and high blood glucose index (LBGI/HBGI) during all the predefined time blocks in the intervention period

Glycemic variability measured as standard deviation (SD), coefficient of variation (CV) and low and high blood glucose index (LBGI/HBGI) during all the predefined time blocks in the intervention period

Glycemic variability measured as standard deviation (SD), coefficient of variation (CV) and low and high blood glucose index (LBGI/HBGI) during all the predefined time blocks in the intervention period

Exercise time: The time the participant has recorded start and end of exercise session during study day 1 -study day 6

Exercise time: The time the participant has recorded start and end of exercise session during study day 1 -study day 6

Total carbohydrate intake registered from the insulin pumps during all the predefined time blocks in the intervention period

Total carbohydrate intake registered from the insulin pumps during all the predefined time blocks in the intervention period

Total carbohydrate intake registered from the insulin pumps during all the predefined time blocks in the intervention period

Total carbohydrate intake registered from the insulin pumps during all the predefined time blocks in the intervention period

Total carbohydrate intake registered from the insulin pumps during all the predefined time blocks in the intervention period

Total carbohydrate intake registered from the insulin pumps during all the predefined time blocks in the intervention period

Exercise time: The time the participant has recorded start and end of exercise session during study day 1 -study day 6

Carbohydrate interventions for prevention and treatment of hypoglycemia registered by the participants in the booklet for the primary and total intervention period

Per protocol analysis and intention-to-treat analysis c) Secondary intervention period: 08:00h day 1 - 08:00h day 8 (= 7 x 24-hour days).

Carbohydrate interventions for prevention and treatment of hypoglycemia registered by the participants in the booklet for the primary and total intervention period

Per protocol analysis and intention-to-treat analysis c) Secondary intervention period: 08:00h day 1 - 08:00h day 8 (= 7 x 24-hour days).

Change in total daily insulin dose (basal and bolus insulin) of 7 days prior to screening day and during the primary and total intervention period

Change in total daily insulin dose (basal and bolus insulin) of 7 days prior to screening day and during the primary and total intervention period

Exercise time: The time the participant has recorded start and end of exercise session during study day 1 -study day 6

Physical activity energy expenditure (accelerometer and heart rate based) measured as kcal during all predefined time blocks

Physical activity energy expenditure (accelerometer and heart rate based) measured as kcal during all predefined time blocks

Physical activity energy expenditure (accelerometer and heart rate based) measured as kcal during all predefined time blocks

Physical activity energy expenditure (accelerometer and heart rate based) measured as kcal during all predefined time blocks

Physical activity energy expenditure (accelerometer and heart rate based) measured as kcal during all predefined time blocks

Exercise time: The time the participant has recorded start and end of exercise session during study day 1 -study day 6

Exercise time: The time the participant has recorded start and end of exercise session during study day 1 -study day 6

Exercise time: The time the participant has recorded start and end of exercise session during study day 1 -study day 6

Exercise time: The time the participant has recorded start and end of exercise session during study day 1 -study day 6

Exercise time: The time the participant has recorded start and end of exercise session during study day 1 -study day 6

Exercise time: The time the participant has recorded start and end of exercise session during study day 1 -study day 6

Exercise time: The time the participant has recorded start and end of exercise session during study day 1 -study day 6

Exercise time: The time the participant has recorded start and end of exercise session during study day 1 -study day 6

Inclusion Criteria: Type 1 Diabetes ≥ 2 year Insulin pump ≥ 1 year. Use of carbohydrate counting and the insulin pump bolus calculator for all meals Exclusion Criteria: Use of anti-diabetic medicine (other than insulin), per oral or injected corticosteroids or other drugs affecting glucose metabolism during the intervention period or within 30 days prior to study start Known or suspected alcohol or drug abuse Other concomitant medical or psychological condition that according to the investigator's assessment makes the participant unsuitable for study participation Females who are pregnant, breast-feeding or intend to become pregnant or are not using adequate contraceptive methods Inability to understand the participants' information and to give informed consent Chronic use or unable to stop acetaminophen (paracetamol) use Allergy to the patch of CGM Hypoglycemia unawareness, quantified by Pedersen-Bjergaard Severe hypoglycemia within the last year Vigorous-intensity exercise for more than 60 minutes on 3 days or more per week

Data are processed and merged into at least one scientific article published in international peer-reviewed scientific journal. Positive, negative and inconclusive results will be published as soon as scientifically justifiable.

Steineck IIK, Ranjan AG, Schmidt S, Norgaard K. Time spent in hypoglycemia is comparable when the same amount of exercise is performed 5 or 2 days weekly: a randomized crossover study in people with type 1 diabetes. BMJ Open Diabetes Res Care. 2021 Jan;9(1):e001919. doi: 10.1136/bmjdrc-2020-001919.