AimsTo assess the determinants of exercise training-induced improvements in glucose control (HbA1C) including changes in serum total adiponectin and FFA concentrations, and skeletal muscle peroxisome proliferator-activated receptor-? coactivator-1? (PGC-1?) protein content.
MethodsA sub-cohort (n?=?35; 48% men; 74% Caucasian) from the HART-D study undertaking muscle biopsies before and after 9 months of aerobic (AT), resistance (RT), or combination training (ATRT).
ResultsChanges in HbA1C were associated with changes in adiponectin (r?=?-0.45, P?=?0.007). Participants diagnosed with type 2 diabetes for a longer duration had the largest increase in PGC-1? (r?=?0.44, P?=?0.008). Statistical modeling examining changes in HbA1C suggested that male sex (P?=?0.05), non-Caucasian ethnicity (P?=?0.02), duration of type 2 diabetes (r?=?0.40; P<0.002) and changes in FFA (r?=?0.36; P<0.004), adiponectin (r?=?-0.26; P<0.03), and PGC-1? (r?=?-0.28; P?=?0.02) explain ?65% of the variability in the changes in HbA1C.
ConclusionsDecreases in HbA1C after 9 months of exercise were associated with shorter duration of diabetes, lowering of serum FFA concentrations, increasing serum adiponectin concentrations and increasing skeletal muscle PGC-1? protein expression.
Trial registrationClinicalTrials.gov NCT00458133.