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Updated: Oct 19, 2026

Using a Combination of Indirect Calorimetry, Infrared Thermography, and Blood Glucose Levels to Measure Brown Adipose Tissue Thermogenesis in Humans
Published on: June 2, 2023
Cardiovascular and metabolic responses during 30 minutes of treadmill exercise shortly after consuming a small,
D C Diboll1, W T Boone, L R Lindsey
1School of Human Performance and Recreation, University of Southern Mississippi, USA. ddiboll@csubak.edu
Abstract:
Fourteen male endurance runners (VO2peak = 64.8 +/- 8.7 ml x kg(-1) x min(-1)) participated in this study to determine the cardiovascular and metabolic responses during 30 minutes of treadmill running at a moderate intensity soon after consuming a small, high-carbohydrate meal (CHO-M). In randomized order on separate days, subjects either consumed the CHO-M (2088 kJ; 77% carbohydrate) 15 minutes prior to running or they fasted (FAST). Data were collected for 5 minutes beginning at 5, 15, and 25 minutes of the 30-minute run. Heart rate (HR) was determined, a metabolic measurement cart was used to determine VO2 and respiratory exchange ratio (RER), and the CO2 rebreathing procedure (Collier plateau method) was used to determine cardiac output (Q). Statistical analyses indicated that the CHO-M did not affect HR, stroke volume, Q, VO2, or RER compared to FAST. However, all grouped CHO-M and FAST variables, except VO2, changed significantly across the 30-minute exercise session. These data suggest that a small, high-carbohydrate meal does not alter cardiovascular and metabolic function during moderate-intensity exercise in endurance-trained subjects.
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