Effects of High-Intensity Interval Exercise versus Moderate Continuous Exercise on Glucose Homeostasis and Hormone Response in Patients with Type 1 Diabetes Mellitus Using Novel Ultra-Long-Acting Insulin

Abstract

Introduction: We investigated blood glucose (BG) and hormone response to aerobic high-intensity interval exercise (HIIE) and moderate continuous exercise (CON) matched for mean load and duration in type 1 diabetes mellitus (T1DM).

Material and methods: Seven trained male subjects with T1DM performed a maximal incremental exercise test and HIIE and CON at 3 different mean intensities below (A) and above (B) the first lactate turn point and below the second lactate turn point (C) on a cycle ergometer. Subjects were adjusted to ultra-long-acting insulin Degludec (Tresiba/ Novo Nordisk, Denmark). Before exercise, standardized meals were administered, and short-acting insulin dose was reduced by 25% (A), 50% (B), and 75% (C) dependent on mean exercise intensity. During exercise, BG, adrenaline, noradrenaline, dopamine, cortisol, glucagon, and insulin-like growth factor-1, blood lactate, heart rate, and gas exchange variables were measured. For 24 h after exercise, interstitial glucose was measured by continuous glucose monitoring system.

Results: BG decrease during HIIE was significantly smaller for B (p = 0.024) and tended to be smaller for A and C compared to CON. No differences were found for post-exercise interstitial glucose, acute hormone response, and carbohydrate utilization between HIIE and CON for A, B, and C. In HIIE, blood lactate for A (p = 0.006) and B (p = 0.004) and respiratory exchange ratio for A (p = 0.003) and B (p = 0.003) were significantly higher compared to CON but not for C.

Conclusion: Hypoglycemia did not occur during or after HIIE and CON when using ultra-long-acting insulin and applying our methodological approach for exercise prescription. HIIE led to a smaller BG decrease compared to CON, although both exercises modes were matched for mean load and duration, even despite markedly higher peak workloads applied in HIIE. Therefore, HIIE and CON could be safely performed in T1DM.

Trial registration: ClinicalTrials.gov NCT02075567 http://www.clinicaltrials.gov/ct2/show/NCT02075567.

Conflict of interest statement

Competing Interests: No conflict of interest: Othmar Moser, Gerhard Tschakert, Alexander Mueller, Werner Groeschl, Barbara Obermayer-Pietsch and Peter Hofmann. Duality of interests: Gerd Koehler has received lecture fees from Novo Nordisk, AstraZeneca, Bristol-Myers Squibb, Roche Diagnostics, Novartis, MSD and Eli Lilly. Thomas R. Pieber has participated in advisory panels and acted as a consultant for Novo Nordisk. This does not alter the authors' adherence to PLOS ONE policies on sharing data and material.

Figures

Fig 1. Consort flow diagram.

CON: moderate continuous exercise, HIIE: short high-intensity interval exercise.

Fig 2. Timeline chart of the study procedure.

CGM: Continuous glucose monitoring system, ICE: Incremental exercise, LTP1: Lactate turn point 1, LTP2: Lactate turn point 2, CON: Moderate continuous exercise, HIIE: short high-intensity interval exercise.

Fig 3. Blood lactate (La) performance curve during the incremental exercise test.

A, B, and C represent the target mean loads for both continuous exercise and high-intensity interval exercise. LTP1: first lactate turn point; LTP2: second lactate turn point; Pmax: maximal power output. Values are given as mean and SD.

Fig 4. Comparison of blood lactate response (La) during high-intensity interval exercise (dotted line) vs. continuous exercise (full line) for mean exercise intensities A, B, and C.

Values are given as mean and SD. “*” represents significance.

Fig 5. Comparison of delta blood glucose (BG) during high-intensity interval exercise vs. continuous exercise for mean exercise intensities A, B, and C.

Values are given as mean and SD. “*” represents significance.

Fig 6. Comparison of blood glucose (BG) decrease during high-intensity interval exercise (dotted line) vs. continuous exercise (full line) for exercise intensities A, B, and C.

Values are given as mean and SD.

Fig 7. Comparison of hormone response during high-intensity interval exercise (dotted line) vs. continuous exercise (full line) for mean exercise intensities A, B, and C.

(A) Catecholamine response. Values are given as mean and SD. (B) Glucagon, cortisol and IGF-1. IGF-1: insulin-like growth factor-1. Values are given as mean and SD.

Fig 8. Comparison of the respiratory exchange ratio (RER) response during high-intensity interval exercise (dotted line) vs. continuous exercise (full line) for mean exercise intensities A, B, and C.

Values are given as mean.

Fig 9. Comparison of heart rate (HR) response during high-intensity interval exercise (dotted line) vs. continuous exercise (full line) for mean exercise intensities A, B, and C.

Values are given as mean.