Trends of glucose, lactate and ketones during anaerobic and aerobic exercise in subjects with type 1 diabetes: The ACTION‐1 study

Abstract

Background Exercise is part of type 1 diabetes (T1D) management due to its cardiovascular and metabolic benefits. However, despite using continuous glucose monitoring, many patients are reluctant to exercise because of fear for hypoglycaemia. Aims We assessed trends in glucose, lactate and ketones during anaerobic and aerobic exercise in people with T1D and compared incremental area under the curve (AUC) between both exercises. Methods Twenty‐one men with T1D (median [IQR]: age 29 years [28–38], body mass index (BMI) 24.4 kg/m2 [22.3–24.9], HbA1c 7.2% [6.7–7.8]), completed a cardiopulmonary exercise test (CPET) and a 60‐min aerobic exercise (AEX) at 60% VO2peak on an ergometer bicycle within a 6‐week period. Subjects consumed a standardised breakfast (6 kcal/kg, 20.2 g CHO/100 ml) before exercise without pre‐meal insulin and basal insulin for pump users. Results During CPET, glucose levels increased, peaking at 331 mg/dl [257–392] 1–3 h after exercise and reaching a nadir 6 h after exercise at 176 mg/dl [118–217]. Lactate levels peaked at 6.0 mmol/L [5.0–6.6] (max 13.5 mmol/L). During AEX, glucose levels also increased, peaking at 305 mg/dl [245–336] 80 min after exercise and reaching a nadir 6 h after exercise at 211 mg/dl [116–222]. Lactate levels rose quickly to a median of 4.3 mmol/L [2.7–6.7] after 10 min. Ketone levels were low during both tests (median ≤ 0.2 mmol/L). Lactate, but not glucose or ketone AUC, was significantly higher in CPET compared to AEX (p = 0.04). Conclusions Omitting pre‐meal insulin and also basal insulin in pump users, did prevent hypoglycaemia but induced hyperglycaemia due to a too high carbohydrate ingestion. No ketosis was recorded during or after the exercises. Clinical Trial Registration: ClinicalTrials.gov: NCT05097339

Early feasibility study with an implantable near-infrared spectroscopy sensor for glucose, ketones, lactate and ethanol

“…Furthermore, high levels of lactate may acutely inhibit the action of insulin on peripheral glucose uptake, an effect similar to that of the counterregulatory hormones [21,22,24]. We and others noticed that the rise in glucose is preceded by a rise in lactate [22,24].). In future automated insulin delivery systems, integration of CLM data might obviate the need of the user to announce exercise (~60 min before).…”

“…In high-intensity exercise, a high lactate level itself can moreover contribute to hyperglycemia because lactate acts as an alternative substrate for glucose and provides gluconeogenic precursors for hepatic glucose production [21]. Furthermore, high levels of lactate may acutely inhibit the action of insulin on peripheral glucose uptake, an effect similar to that of the counterregulatory hormones [21,22,24]. We and others noticed that the rise in glucose is preceded by a rise in lactate [22,24].).…”

“…Physical activity is a cornerstone of a healthy lifestyle but induces rapid fluctuations in glycemia in individuals with T1D due to glucose consumption by active muscles, and changes in counter-regulatory hormone levels. Insufficient information and knowledge to manage exercise-induced changes in glycemic control and fear of hypoglycemia can make individuals with T1D reluctant to or refrain from intense or prolonged physical activity [21][22][23].…”

Assessment of selected muscle and intestinal damage markers after maximum-intensity exercise in men with type 1 diabetes treated with a personal insulin pump

“…Moreover, higher levels of lactate may sharply inhibit the insulin impact on peripheral glucose uptake, which is an action similar to that of counterregulatory hormones [29]. Peri-exercise lactate monitoring in T1D may provide additional information to optimize physical activity [30]. Myoglobin is a protein responsible for the storage of oxygen in striated muscle tissue.…”

“…In patients with T1D, the increase in blood lactate concentrations after physical exercise was shown to be larger in older subjects and did not depend on gender, insulin administration method, or training in a sports club vs. recreational play [63]. Compared with aerobic exercise, a cardiopulmonary exercise test was associated with higher lactate levels in adult men with T1D [30].…”