Effect of High-Intensity Interval Training on Glycemic Control in Adults With Type 1 Diabetes and Overweight or Obesity: A Randomized Controlled Trial With Partial Crossover

Abstract

To study the effect of 12 weeks of high-intensity interval training (HIIT) on glycemic control in adults with type 1 diabetes and overweight or obesity. RESEARCH DESIGN AND METHODS Thirty inactive adults with type 1 diabetes who had BMI ‡25 kg/m 2 and HbA 1c ‡7.5% were randomized to 12 weeks of either HIIT exercise intervention consisting of 4 3 4-min HIIT (85-95% peak heart rate) performed thrice weekly or usual care control. In a partial crossover design, the control group subsequently performed the 12-week HIIT intervention. The primary end point was the change in HbA 1c from baseline to 12 weeks. Glycemic and cardiometabolic outcomes were measured at 0, 12, and 24 weeks. RESULTS Participants were aged 44 6 10 years with diabetes duration 19 6 11 years and BMI 30.1 6 3.1 kg/m 2. HbA 1c decreased from 8.63 6 0.66% at baseline to 8.10 6 1.04% at 12 weeks in the HIIT intervention group (P 5 0.01); however, this change was not significantly different from the control group (HIIT 20.53 6 0.61%, control 20.14 6 0.48%, P 5 0.08). In participants who undertook at least 50% of the prescribed HIIT intervention, the HbA 1c reduction was significantly greater than control (HIIT 20.64 6 0.64% [n 5 9], control 20.14 6 0.48% [n 5 15], P 5 0.04). There were no differences in insulin dose, hypoglycemia on continuous glucose monitoring, blood pressure, blood lipids, body weight, or body composition between groups. CONCLUSIONS Overall, there was no significant reduction in HbA 1c with a 12-week HIIT intervention in adults with type 1 diabetes. However, glycemic control may improve for people who undertake HIIT with greater adherence. Regular exercise is recommended for people with type 1 diabetes (1,2) and can provide multiple health benefits, including improvements in body weight, cardiorespiratory fitness, and lipid profile (3). Physical activity is associated with better glycemic control in cross-sectional studies of people with type 1 diabetes (2,4).

Effects of a HIIT Protocol on Cardiovascular Risk Factors in a Type 1 Diabetes Mellitus Population

“…Our results revealed that fasting glucose was reduced by 7.8% in line with previous research with similar characteristics that reported a 7.5% reduction [31]. In the same way, a 11.2% mean glucose reduction was reported by Lee and coworkers, using continuous glucose monitoring during 14 days in overweight and obese volunteers [28]. Investigations that examined glucose behavior after a period of HIIT training, but in Type 2 Diabetes people and subjects with metabolic syndrome, also showed a median reduction in fasting glucose of 16 mg/dL (similar to 11mg/dL reported in the present study) [51].…”

“…This training method consisted of 20 min at 50% HR peak in weeks 1-2, four 1-min intervals at 80% HRmax interspersed with 5-min active recovery at 50% HR peak in weeks 3-4, and six 1-min intervals at 85% HR peak with the same rest intervals in the last four weeks. In contrast, Lee and her research group showed no improvements in VO 2max after a 12-week HIIT protocol, which consisted of 4 bouts of 4 min at 85-95% HR peak interspersed with 3-min recovery intervals at 50-70% HR peak applied in T1DM and overweight people [28], but caution is needed with those results since authors reported inaccuracies that affected to the methodological quality associated with the gas analyzer reliability.…”

“…Living with obesity or overweight has been widely linked to an enhanced risk of a cardiovascular accident [26], so preventing this situation is a key point in T1DM patients' healthcare. HIIT has shown interesting effects on body composition in healthy individuals [27] and disappointing results in obese and overweight people with T1DM [28,29], so it is important to expand the analysis of this topic.…”

Effect of High-Intensity Interval Training on Quality of Life, Sleep Quality, Exercise Motivation and Enjoyment in Sedentary People with Type 1 Diabetes Mellitus

“…To the best of our knowledge, there is only one previous publication that analyses HRQoL in T1DM after a HIIT protocol [ 47 ]. However, the aforementioned study used obese or overweight participants and the training consisted of 4 bouts of 4 min at 85–95% HR peak interspersed with 3-min recovery intervals at 50–70% HR peak for 12 weeks.…”

Managing arterial health in adults with metabolic diseases: Is high-intensity interval exercise the answer? Response to the commentary by Lopes et al.

“… 11 Yet another study conducted by our group found no reduction in PWV following 12 weeks of HIIE in adults with type 1 diabetes (4 × 4 min at 85%–95% peak heart rate (HR peak ) interspersed with 3 min of active recovery at 50%–70%HR peak , 3 times per week). 14 This result was surprising, given that we did not find a significant difference in transient responses between adults with type 1 or type 2 diabetes in central arterial stiffness, wave reflections, or hemodynamics following a bout of HIIE. 2 Similarly, Holloway et al 15 found that 6 weeks of HIIE in young, healthy adults resulted in no change in PWV.…”