The Impact of Passive Heat Treatment on Glycaemic Response During an Oral Glucose Tolerance Test in Diabetic Patients

Type 2 diabetes mellitus (T2DM) is a metabolic disease with a rapidly increasing incidence world-wide. The disease is characterizedby a decreased glucose tolerance as a result of insulin resistance, resulting in poor blood glycaemic control. Blood glucose loweringmedications are widely available, but their effect stagnates as T2DM progresses. New treatment regimens are required to combatthe disease. Although therapies such as physical exercise have been shown to induce beneficial effects on glycaemic control inT2DM patients, not all patients are able to perform exercise. Passive heating treatment (PHT) might be an alternative strategy toreduce insulin resistance, as it has been postulated to have comparable effects on the cardiovascular system as exercise. PHT hasbeen linked to numerous health benefits, including improved cardiovascular- and pulmonary function, pain alleviation and metabolichealth. In addition, long term use of PHT shows promising effects on glycaemic control in T2DM patients. However, the acute effectsof PHT on glucoregulation are yet to be determined. Therefore, in this study we will assess the acute impact of passive heat treatment on the post-prandial glycaemic response during an OGTT in T2DM patients

Inclusion Criteria:Aged ≥50 years oldBody mass index 18.5 - 35 kg/m2DM type 2Using oral blood glucose lowering medicationAble to give informed consentExclusion Criteria:Insulin dependenceChanges in diabetes medication in the past 3 monthsAllergy for one of the food items used>5% weight change in the previous 6 monthsParticipating in a structured (progressive) exercise program, or in the past 3 months.Frequent (once per week or more) user of infrared (or traditional) sauna in the past 3 monthsInability to tolerate sauna/high temperaturesSmokingDiagnosed with cardiovascular disease (e.g. unstable angina pectoris or recent myocardial infarction), kidney failure (eGFR < 60 ml/min/1.73m2), rheumatoid arthritisDiagnosed musculoskeletal, GI tract, metabolic (except diabetes) or pulmonary (e.g. COPD) disorders that are expected to influence study outcomesHaving a pacemaker, defibrillator, or any other type of metal implant