During hypoglycemia after high-intensity interval training, brain lactate decreased ~30% below baseline in patients with type 1 diabetes and impaired awareness of hypoglycemia, unlike controls.
Observational (n=18)
Does HIIT-induced hyperlacticacidemia affect brain lactate levels differently during hypoglycemia in patients with type 1 diabetes and IAH compared to those with normal awareness or healthy controls?
Patients with type 1 diabetes and impaired awareness of hypoglycemia show enhanced brain lactate transport and increased lactate oxidation during hypoglycemia following exercise.
Since altered brain lactate handling has been implicated in the development of impaired awareness of hypoglycemia (IAH) in type 1 diabetes, the capacity to transport lactate into the brain during hypoglycemia may be relevant in its pathogenesis. High-intensity interval training (HIIT) increases plasma lactate levels. We compared the effect of HIIT-induced hyperlacticacidemia on brain lactate during hypoglycemia between 1) patients with type 1 diabetes and IAH, 2) patients with type 1 diabetes and normal awareness of hypoglycemia, and 3) healthy participants without diabetes (n = 6 per group). All participants underwent a hypoglycemic (2.8 mmol/L) clamp after performing a bout of HIIT on a cycle ergometer. Before HIIT (baseline) and during hypoglycemia, brain lactate levels were determined continuously with J-difference–editing 1H-MRS, and time curves were analyzed using nonlinear mixed-effects modeling. At the beginning of hypoglycemia (after HIIT), brain lactate levels were elevated in all groups but most pronounced in patients with IAH. During hypoglycemia, brain lactate decreased ∼30% below baseline in patients with IAH but returned to baseline levels and remained there in the other two groups. Our results support the concept of enhanced lactate transport as well as increased lactate oxidation in patients with type 1 diabetes and IAH.
Wiegers et al. (Thu,) conducted a observational in Type 1 diabetes with impaired awareness of hypoglycemia (n=18). Type 1 diabetes with impaired awareness of hypoglycemia vs. Type 1 diabetes with normal awareness of hypoglycemia, and healthy participants without diabetes was evaluated on Brain lactate levels during hypoglycemia. During hypoglycemia after high-intensity interval training, brain lactate decreased ~30% below baseline in patients with type 1 diabetes and impaired awareness of hypoglycemia, unlike controls.