HIT on Hypoglycemic Risk in Type 1 Diabetes (T1D)

Study Overview
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Brief Summary
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There is clear evidence that regular exercise improves wellbeing and reduces the risk of diabetes related complications in people with type 1 diabetes. However, many people with type 1 diabetes do not exercise regularly. The primary reason for this is fear of hypoglycaemia and loss of glycaemic control associated with exercise. This loss of glycaemic control is associated with traditional moderate intensity continous aerobic exercise advocated in the guidelines for exercise in people with type 1 diabetes. Recent work (unpublished) from our lab suggests high intensity interval training (HIT) may reduce the risk of hypoglycaemia in people with type 1 diabetes, however stronger evidence is needed before firm conclusions can be drawn. Therefore, the aim of this study is to determine the effects of HIT on glycaemic control in people with type 1 diabetes compared to no exercise and traditional moderate intensity continous exercise. 24 people with type 1 diabetes will be recruited to complete a randomised counterbalanced cross over study comparing 3x 2-week interventions periods. During these intervention periods participant will maintain their habitual lifestyle but complete either no exercise (control), traditional moderate intensity continous exercise or high intensity interval training. Throughout the intervention periods participants glycaemic control will be monitored using a flash glucose monitor.

Official Title
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Can High Intensity Interval Training Reduce Fear of Hypoglycaemia and Improve Glycaemic Control in People With Type 1 Diabetes?

Conditions
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Type1diabetes

Intervention / Treatment
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* Behavioral: high intensity interval training
* Behavioral: moderate intensity continous training


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: T1D diagnosis more than 6 months ago (to ensure participants are out of the honeymoon period), Using a basal bolus insulin regime or insulin pump therapy BMI ≤ 32 kg.m-2 Exclusion Criteria: Pregnancy (or planning pregnancy) Disability preventing participation in an exercise regime Angina Autonomic neuropathy Medication that affects heart rate (this will affect estimation of fitness) Major surgery planned within 6 weeks of study Uncontrolled blood pressure Significant history of hyperglycaemia History of severe hypoglycaemia requiring third party assistance within the last 3 months Severe non-proliferative and unstable proliferative retinopathy

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 55 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control<br>Participants will continue with their habitual lifestyle but perform no exercise for 2 weeks | |
| Active Comparator: Moderate intensity continous training<br>Participants will complete moderate intensity continous training during a 2 week intervention period | Behavioral: moderate intensity continous training<br>* Participants will complete 6 sessions of moderate intensity continous training during a 2 week intervention period. Participants will be asked to complete 30 minutes of continuous exercise.<br>|
| Experimental: high intensity interval training<br>Participants will complete high intensity interval training during a 2 week intervention period | Behavioral: high intensity interval training<br>* Participants will complete 6 sessions of high intensity interval training during a 2 week intervention period. The programme involves repeated 1 minute bouts of simple on the spot movements interspersed with 1 minute of rest.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Severe hypoglycaemia | Number of severe hypoglycaemic events (<3mmol/l) during the 2 week intervention period | 2 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean glucose | mean glucose level over 2 week recording period | 2 weeks | 
| % of time in level 2 hypoglycaemia (<3.0mmol/L) | % of time in level 2 hypoglycaemia (<3.0mmol/L) over 2 week recording period | 2 weeks | 
| % of time in level 1 hypoglycaemia (3.0-3.9mmol/L) | % of time in level 1 hypoglycaemia (3.0-3.9mmol/L) over 2 week recording period | 2 weeks | 
| % of time in target range (3.9-10.0mmol/L) | % of time in target range (3.9-10.0mmol/L) over 2 week recording period | 2 weeks | 
| % of time in level 1 hyperglycaemia (10.0-13.9mmol/L) | % of time in level 1 hyperglycaemia (10.0-13.9mmol/L) over 2 week recording period | 2 weeks | 
| % of time in level 2 hyperglycaemia (>13.9mmol/L) | % of time in level 2 hyperglycaemia (>13.9mmol/L) over 2 week recording period | 2 weeks | 
| glycaemic variability (coefficient of variation and Standard Deviation) | glycaemic variability over 2 week recording period | 2 weeks | 
| area under the curve of episodes of hypoglycaemia and hyperglycaemia | area under the curve of episodes of hypoglycaemia and hyperglycaemia 2 week recording period | 2 weeks |