Improved Metabolic Flexibility Postbreakfast after Exercise Intervention in People with T2DM

Exercise provides many metabolic benefits for people with type 2 diabetes; nevertheless, the ability to switch substrate oxidation from fat to carbohydrate and back, known as metabolic flexibility (MetFlex), in response to prolonged exercise training has not been thoroughly explored. Purpose: The goal of this analyses was to investigate changes in MetFlex after an exercise intervention. We enrolled healthy sedentary participants with obesity (HSO) and participants with type 2 diabetes (T2DM) in a 10-week aerobic exercise intervention. Methods: Seventeen participants with T2DM (8 females; 52.9 years; BMI= 36.9 kg/m 2 and 9 males; 48.8 years; BMI= 33.3 kg/m 2 ) and seven HSO (5 females; 44.8 years, BMI= 37.6 kg/m 2 and 2 males; 46.5 years, BMI= 36.2 kg/m 2 ) completed the intervention. MetFlex was assessed as the respiratory quotient (RQ) kinetic response after ingesting a standard high CHO breakfast during a 24-h energy expenditure measurement in a whole-room respiratory chamber. Briefly, the kinetics between the lowest RQ and highest RQ points were analyzed by a simple linear regression between time (1-minute resolution) and RQ units (RQ Units ). Individual data were time-aligned and averaged for each group and moments (PRE and POST intervention), then slopes and intercepts for T2DM vs. HSO groups and PRE vs. POST were compared using a multiple regression model. Results: At PRE-intervention, HSO group had a significantly lower intercept than T2DM (HSO=0.737 vs. T2DM=0.705; P ) and slower RQ kinetics as demonstrated by a greater slope (HSO=0.00448 RQ Units /min vs. T2DM=0.00332 RQ Units /min; F=18.1, P=0.001 ). After the exercise intervention only T2DM significantly increased their slope (POST= 0.003944 RQ Units /min; F=6.47, P=0.013 ). Conclusions: Our results indicate that participants with diabetes significantly improve MetFlex following a prolonged aerobic exercise intervention. Disclosure E.A. Carnero: None. C.P. Bock: None. N. Stephens: None. R.E. Pratley: Other Relationship; Self; AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc., Eisai Inc., GlaxoSmithKline plc., Janssen Pharmaceuticals, Inc., Lexicon Pharmaceuticals, Inc., Ligand Pharmaceuticals, Inc., Eli Lilly and Company, Merck u0026 Co., Inc., Novo Nordisk Inc., Pfizer Inc., Sanofi-Aventis, Takeda Development Center Americas, Inc.. S.R. Smith: None. L.M. Sparks: None.