Blood Glucose Levels of Subelite Athletes During 6 Days of Free Living

Abstract

Background: Continuous glucose monitoring (CGM) devices, with their 1-5 min measurement interval, allow blood glucose (BG) concentration dynamics to be captured more frequently and less invasively than traditional BG measures. One cohort CGM could provide insight is athletes. This study investigates what impact their heightened energy expenditure and dietary intake may have on their ability to achieve optimal BG. Methods:Ten subelite athletes (resting HR<60 bpm, training>6 hrs per week) were recruited. Two Ipro2 CGM devices (Medtronic Minimed, Northridge, CA) were inserted into the abdomen and remained in place for ~6 days. Time in band was calculated as the percentage of CGM BG measurements with in the 4.0-6.0 mmol/L. Fasting glucose was calculated using CGM calibration BG measurements and postprandial glucose response was also calculated using the CGM values.Results: 4/10 athletes studied spent more than 70% of the total monitoring time above 6.0 mmol/L even with the 2-hour period after meals is excluded. Fasting BG was also in the ADA defined prediabetes range for 3/10 athletes. Only 1 participant spent substantial time below 4.0 mmol/L which was largely due to significantly lower energy intake compared to recommendations. Conclusions:Contrary to expectations high BG appears to be more of a concern for athletes then low BG even in those with the highest energy expenditure and consuming below the recommended carbohydrate intake. This study warrants further investigation on the recommended diets and the BG of athletes to better determine the causes and impact of this hyperglycemia on overall athlete health.

Dose–response between frequency of interruption of sedentary time and fasting glucose, the dawn phenomenon and night‐time glucose in Type 2 diabetes

“…Changes in glucose variables were calculated by subtracting glucose values before treatment conditions from glucose values after treatment conditions. The CGM glucose value just before the start of breakfast was defined as fasting glucose (pre‐breakfast glucose) . The dawn phenomenon was calculated by subtracting nocturnal (starting at midnight) nadir glucose from pre‐breakfast glucose .…”

ISPAD Clinical Practice Consensus Guidelines 2018: Exercise in children and adolescents with diabetes

“…This is entirely dependent on blood glucose responses to activity. 61 Ensuring that total energy, carbohydrate, and protein intake meet requirements will contribute to the prevention of hypoglycemia through adequate repletion of glycogen stores 62 taking into account the fact that the amount of insulin can also affect the outcome. Balanced against this is the need to ensure that advice on hypoglycemia prevention does not increase consumption of less healthful foods as a result of being more active.…”

“…If the usual routine is a meal or snack consumed within 1 to 2 hours of completing the exercise, then supplemental nutrition postexercise may not be required. This is entirely dependent on blood glucose responses to activity . Ensuring that total energy, carbohydrate, and protein intake meet requirements will contribute to the prevention of hypoglycemia through adequate repletion of glycogen stores taking into account the fact that the amount of insulin can also affect the outcome.…”

Acute effect of low and moderate glycemic index drinks on plasma glucose level in professional football players during prolonged intermittent exercise

“…It is long known that plasma glucose concentration can increase in response to intermittent sport activity due to an increase in circulating catecholamine (Bangsbo 1994;Jacob et al 2004;Zouhal et al 2008;Thomas at al. 2016) due to stimulation of the sympathetic nervous system.…”