Optimal Insulin Correction Factor (ICF) for Post-exercise Hyperglycemia following High-Intensity Training in Adults with Type 1 Diabetes (T1D)—The FIT Study

• Published in: Diabetes (New York, N.Y.) Vol. 67; no. Supplement_1
• Main Authors: ARONSON, RONNIE, BROWN, RUTH E., RIDDELL, MICHAEL
• Format: Journal Article
• Language: English
• Published: 01.07.2018
• ISSN: 0012-1797; 1939-327X
• DOI: 10.2337/db18-732-P

The phenomenon of post-exercise hyperglycemia following high-intensity training (HIT) in T1D patients has led to debate of corrective therapy options but has not been definitively investigated to date. The FIT study was a randomized, cross-over investigation of 4 post-HIT bolus insulin correction strategies in patients with T1D. Patients with T1D (n=18) using multi-daily injections (MDI) were enrolled and underwent an 8-week insulin optimization period using insulin glargine 300 U/mL as their basal insulin. On 4 separate days, each subject performed 25 minutes of HIT. If hyperglycemia (>8.0 mmol/L) resulted, subjects received a bolus insulin correction 15 minutes post-HIT, based on their own ICF, adjusted by one of 4 commonly used multipliers: 0%, 50%, 100%, or 150%. At 180 minutes following bolus correction, change in plasma glucose (PG) was greatest in both the 100% (-4.7 mmol/L) and 150% (-5.3 mmol/L) ICF arms, vs. 50% (-2.3 mmol/L, p<.05) and 0% (+1.0 mmol/L, p<.05) (Figure). Percent time in euglycemia (4.0-8.0 mmol/L) progressively increased with each increasing correction factor. Hypoglycemia was rare and only seen in the 150% arm. In correction of post-exercise hyperglycemia following HIT, correction based on a patient’s usual ICF is safe and effective. Optimal BG reduction, with no hypoglycemia, occurred in the 100% ICF correction arm.