TY - JOUR
T1 - Pancreatic beta-cell function is a stronger predictor of changes in glycemic control after an aerobic exercise intervention than insulin sensitivity
AU - Solomon, Thomas
AU - Malin, Steven K
AU - Karstoft, Kristian
AU - Kashyap, Sangeeta R
AU - Haus, Jacob M
AU - Kirwan, John P
PY - 2013/10
Y1 - 2013/10
N2 - Context: Understanding intersubject variability in glycemic control following exercise training will help individualize treatment. Objective: Our aim was to determine whether this variability is related to training-induced changes in insulin sensitivity or pancreatic β-cell function. Design, Setting, and Participants: We conducted an observational clinical study of 105 subjects with impaired glucose tolerance or type 2 diabetes. Interventions and Main Outcome Measures: Individual subject changes in fitness (VO 2max), gly-cemia (glycosylated hemoglobin, fasting glucose, oral glucose tolerance test), insulin sensitivity (hyperinsulinemic-euglycemic clamp), oral glucose-stimulated insulin secretion (GSIS), and disposition index (DI) were measured following 12 to 16 weeks of aerobic exercise training. Regression analyses were used to identify relationships between variables. Results: After training, 86% of subjects increased VO2max and lost weight. Glycosylated hemoglobin, fasting glucose, and 2-hour oral glucose tolerance test were reduced in 69%, 62%, and 68% of subjects, respectively, while insulin sensitivity improved in 90% of the participants. Changes in glycemic control were congruent with changes in GSIS such that 66% of subjects had a reduction in first-phase GSIS, and 46% had reduced second-phase GSIS. Training increased first- and second-phase DI in 83% and 74% of subjects. Training-induced changes in glycemic control were related to changes in GSIS (P <.05), but not insulin sensitivity or DI, and training-induced improvements in glycemic control were largest in subjects with greater pretraining GSIS. Conclusions: Intersubject variability in restoring glycemic control following exercise is explained primarily by changes in insulin secretion. Thus, baseline and training-induced changes in β-cell function may be a key determinant of training-induced improvements in glycemic control.
AB - Context: Understanding intersubject variability in glycemic control following exercise training will help individualize treatment. Objective: Our aim was to determine whether this variability is related to training-induced changes in insulin sensitivity or pancreatic β-cell function. Design, Setting, and Participants: We conducted an observational clinical study of 105 subjects with impaired glucose tolerance or type 2 diabetes. Interventions and Main Outcome Measures: Individual subject changes in fitness (VO 2max), gly-cemia (glycosylated hemoglobin, fasting glucose, oral glucose tolerance test), insulin sensitivity (hyperinsulinemic-euglycemic clamp), oral glucose-stimulated insulin secretion (GSIS), and disposition index (DI) were measured following 12 to 16 weeks of aerobic exercise training. Regression analyses were used to identify relationships between variables. Results: After training, 86% of subjects increased VO2max and lost weight. Glycosylated hemoglobin, fasting glucose, and 2-hour oral glucose tolerance test were reduced in 69%, 62%, and 68% of subjects, respectively, while insulin sensitivity improved in 90% of the participants. Changes in glycemic control were congruent with changes in GSIS such that 66% of subjects had a reduction in first-phase GSIS, and 46% had reduced second-phase GSIS. Training increased first- and second-phase DI in 83% and 74% of subjects. Training-induced changes in glycemic control were related to changes in GSIS (P <.05), but not insulin sensitivity or DI, and training-induced improvements in glycemic control were largest in subjects with greater pretraining GSIS. Conclusions: Intersubject variability in restoring glycemic control following exercise is explained primarily by changes in insulin secretion. Thus, baseline and training-induced changes in β-cell function may be a key determinant of training-induced improvements in glycemic control.
U2 - 10.1210/jc.2013-2232
DO - 10.1210/jc.2013-2232
M3 - Journal article
C2 - 23966244
SN - 0021-972X
VL - 98
SP - 4176
EP - 4186
JO - Journal of Clinical Endocrinology and Metabolism
JF - Journal of Clinical Endocrinology and Metabolism
IS - 10
ER -
