Increased insulin-stimulated glucose uptake in both leg and arm muscles after sprint interval and moderate-intensity training in subjects with type 2 diabetes or prediabetes

We investigated the effects of sprint interval training (SIT) and moderate-intensity continuous training (MICT) on glucose uptake (GU) during hyperinsulinemic euglycemic clamp and fatty acid uptake (FAU) at fasting state in thigh and arm muscles in subjects with type 2 diabetes (T2D) or prediabetes. Twenty-six patients (age 49, SD 4; 10 women) were randomly assigned into two groups: SIT (n=13) and MICT (n=13). The exercise in the SIT group consisted of 4-6x30 s of all-out cycling with 4-minute recovery and in the MICT group 40- to 60-minute cycling at 60% of VO2peak. Both groups completed six training sessions within two weeks. GU and FAU were measured before and after the intervention with positron emission tomography in thigh (quadriceps femoris, QF; and hamstrings) and upper arm (biceps and triceps brachii) muscles. Whole-body insulin-stimulated GU increased significantly by 25% in both groups, and this was accompanied with significantly increased insulin-stimulated GU in all thigh and upper arm muscles and significantly increased FAU in QF. Within QF, insulin-stimulated GU improved more by SIT than MICT in rectus femoris (P=.01), but not differently between the training modes in the other QF muscles. In individuals with T2D or prediabetes, both SIT and MICT rapidly improve insulin-stimulated GU in whole body and in the thigh and arm muscles as well as FAU in the main working muscle QF. These findings highlight the underused potential of exercise in rapidly restoring the impaired skeletal muscle metabolism in subjects with impaired glucose metabolism.