Continuous glucose monitoring to measure metabolic impact and recovery in sub-elite endurance athletes

Background and motivation: Athletes experience substantial physiological impacts after exhaustive events, including post-exercise hyperglycemia. Objective measurement of athlete recovery is a major goal in sports training to optimize performance. Continuous glucose monitors (CGMs) provide frequent, minimally invasive blood glucose measurements to potentially observe the metabolic impact of a major endurance exercise event and subsequent recovery. Methods: Ten sub-elite athletes were fitted with CGMs. Blood glucose levels (BGLs), exercise, and nutrition were monitored for 4-6 days. Athletes performed an endurance exercise test to exhaustion after 1-2 days of monitoring. Validated State and Substate pattern analyses quantified glycemic level and variability before and after the exercise test, including basal glucose levels and glycemic responses to carbohydrate intake. Results: Glycemic variability and glycemic response to carbohydrate intake increased on the day of the test and returned to normal the next day. Overnight glucose levels remained elevated up to 3-4 days post-test. These results capture the metabolic impact of the test and subsequent recovery. Conclusions and significance: The initial hyperglycemic period and lasting metabolic effects of an endurance test to exhaustion are quantifiable in commercially available CGM devices. The results encourage further investigation into using CGMs to monitor athletic recovery after intense exercise events.

Automated summary

The study reveals that glycemic variability and glycemic response to carbohydrate intake of athletes increase after endurance exercise, while overnight glucose levels remain elevated. These metabolic effects can be quantified using commercially available CGM devices, encouraging further research on monitoring athletic recovery after intense exercise events.