Objective: To investigate if oral glutamine ameliorates exercise- and post-exercise nighttime hypoglycemia in T1DM.

Research Design & Methods: 10 adolescents (15.2 ± 1.4 yrs (SD)), HbA1C 6.9 ± 0.9%, on insulin pumps were studied. Subjects were randomized to receive a glutamine or placebo drink pre-exercise and bedtime (0.25 g/kg/dose). A 3PM exercise session consisted of 4, 15-min treadmill/5-min rests cycles. Pre-exercise BG was 140-150mg/dl and monitored throughout the night. Studies were randomized crossover over 3 weeks.

Results: BGs dropped comparably (52%) during exercise both days. However, the overnight number of hypoglycemic events was higher on glutamine than placebo (≤70 mg/dl, p=0.03 and ≤60, p=0.05). The cumulative probability of nighttime hypoglycemia was increased on glutamine (80%) vs. placebo days (50%) (p=0.02).

Conclusions: Glutamine increased the cumulative probability of post-exercise overnight hypoglycemia compared to placebo in adolescents with T1DM. Whether glutamine may enhance insulin sensitivity post exercise requires further study in T1DM.