Optimal Insulin Correction Factor in Post–High-Intensity Exercise Hyperglycemia in Adults With Type 1 Diabetes: The FIT Study

Abstract

Postexercise hyperglycemia, following high-intensity interval training (HIIT) in patients with type 1 diabetes (T1D), is largely underrecognized by the clinical community and generally undertreated. The aim of this study was to compare four multipliers of an individual's insulin correction factor (ICF) to treat post-HIIT hyperglycemia. RESEARCH DESIGN AND METHODS The FIT study had a randomized, crossover design in physically active subjects with T1D (mean 6 SD age 34.9 6 10.1 years, BMI 25.5 6 2.5 kg/m 2 , and HbA 1c 7.2 6 0.9%) using multiple daily injections. Following an 8-week optimization period, with 300 units/mL insulin glargine used as the basal insulin, subjects performed four weekly sessions of 25 min of HIIT. If hyperglycemia (>8.0 mmol/L) resulted, subjects received a bolus insulin correction 15 min post-HIIT, based on their own ICF, adjusted by one of four multipliers: 0, 50, 100, or 150%. RESULTS Seventeen subjects completed 71 exercise trials, of which 64 (90%) resulted in hyperglycemia. At 40 min postexercise, plasma glucose (PG)

Glucose management for exercise using continuous glucose monitoring (CGM) and intermittently scanned CGM (isCGM) systems in type 1 diabetes: position statement of the European Association for the Study of Diabetes (EASD) and of the International Society for Pediatric and Adolescent Diabetes (ISPAD) endorsed by JDRF and supported by the American Diabetes Association (ADA)

“…Thirty to 60 min prior to the start of prolonged aerobic exercise (>30 min), to reduce hypoglycaemia risk, low glycaemic index carbohydrates can be consumed in those who do not reduce During exercise Independent of the type of exercise, the target sensor glucose ranges should be between 5.0 mmol/l and 10.0 mmol/l (90 mg/dl and180 mg/dl) and, ideally, between 7.0 mmol/l and 10.0 mmol/l (126 mg/dl and 180 mg/dl) for prolonged aerobic exercise for the majority of adults with type 1 diabetes, and slightly higher for those with an increased risk of hypoglycaemia (Table 2) [38] (D), [39] (D). If sensor glucose is expected to increase, as often seen in people performing fasted high-intensity interval training [55,56], resistance training [49,65,66] and, also, in training above the anaerobic threshold [67], then an insulin correction can be administered at the onset of, as well as during exercise (50% of typical correction factor) [68]…”

“…Sensor glucose may be monitored regularly via CGM, or every 15-30 min in the case of isCGM, during the 90 min post-exercise period, and the hypoglycaemia alert can be set at 4.4 mmol/l (80 mg/dl), 5.0 mmol/l (90 mg/dl) or 5.6 mmol/l (100 mg/dl) based on the risk of hypoglycaemia. If sensor glucose is rapidly increasing in the post-exercise phase (detected by CGM when using the rate-of-change alert), then an insulin correction can be considered (50% of typical correction dose) [68] (D), [69] (D). If exercise was performed at a moderate-to-high intensity and/or for a long duration, then glucose may decrease during the acute post-exercise period, as seen in experimental studies [74,77].…”

Glucose management for exercise using continuous glucose monitoring ( CGM ) and intermittently scanned CGM ( isCGM ) systems in type 1 diabetes: position statement of the European Association for the Study of Diabetes ( EASD ) and of the International Society for Pediatric and Adolescent Diabetes ( ISPAD ) endorsed by Moser1, Riddell2, Eckstein3 et al. 2020Pediatric DiabetesSelf Cite501440View full textAdd to dashboardCite

“…increased risk of hypoglycaemia (Table 2) [38](D), [39](D). If sensor glucose is expected to increase, as often seen in people performing fasted high-intensity interval training [55,56], resistance training [49,65,66] and, also, in training above the anaerobic threshold [67], then an insulin correction can be administered at the onset of, as well as during exercise (50% of typical correction factor) [68](D), [69](D).…”

Paradoxical Rise in Hypoglycemia Symptoms With Development of Hyperglycemia During High-Intensity Interval Training in Type 1 Diabetes

“…This study was part of a larger clinical trial evaluating optimal insulin correction for hyperglycemia after HIIT (6). Seventeen fit adults with T1D completed four identical, supervised weekly fasted HIIT sessions comprising three 5-min bouts.…”