Protein Before Exercise Curbs Hypoglycemia

TOPLINE:

Protein intake within 4 hours before exercise may shorten hypoglycemic episodes during moderate physical activity in teens with type 1 diabetes (T1D).

METHODOLOGY:

• For teenagers with T1D, regular physical activity improves blood sugar, insulin sensitivity, and other health measures, but the risk for hypoglycemia is a major barrier.
• In a secondary analysis of the FLEX study, researchers estimated the association between protein intake within 4 hours before moderate to vigorous physical activity bouts and glycemia during and following physical exercise.
• The final sample size included 447 bouts from 112 adolescents with T1D (median age, 14.5 years; 53.6% female) whose physical activity records and 24-hour dietary recall data were collected at baseline and 6 months.
• Data on continuous glucose monitoring (CGM) was a selection criterium and used to calculate the following measures of glycemia:
  • Percentage of time above range (TAR; > 180 mg/dL)
  • Percentage of time in range (TIR; 70-180 mg/dL)
  • Percentage of time below range (TBR;

TAKEAWAY:

• There was a small reduction in TBR during physical activity in patients who consumed 10-19.9 g (−4.41%; P = .04) and > 20 g (−4.83%; P = .02) of protein before moderate to vigorous exercise compared with those who consumed less than 10 g of protein.
• Similarly, protein intakes of 0.125-0.249 g/kg and ≥ 0.25 g/kg were associated with −5.38% (P = .01) and −4.32% (P = .03) reductions in TBR, respectively, compared with less than 0.125 g/kg of protein intake.
• However, the pre-exercise protein consumption was not associated with TAR or TIR during exercise or with any glycemic measurements (TAR, TIR, and TBR) after exercise.
• The benefits of protein intake on glycemia were observed only during moderate-intensity bouts of physical activity, which may reflect differing glycemic trajectories in more high-intensity activity.

IN PRACTICE:

“Consumption of at least 10 g or 0.125 g/kg bodyweight was associated with reduced TBR during moderate to vigorous physical activity, indicating improved safety for adolescents with T1D,” the authors wrote.

SOURCE:

This study, led by Franklin R. Muntis, PhD, Department of Nutrition, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, North Carolina, was published online on January 15, 2024, in Diabetes, Obesity and Metabolism.

LIMITATIONS:

Self-reported measures of dietary intake were prone to underreporting, while moderate-to-vigorous physical activity was often overreported among adolescents. Approximately, 26% of identified bouts of moderate to vigorous physical activity were missing adequate CGM data, excluding participants from the analysis, which may have caused selection bias. There was no time-stamped insulin dosing data available.

DISCLOSURES:

The FLEX study was funded by the National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health. The authors declared no conflicts of interest.