Mechanisms of Fatigability and the Protective Effects of Exercise in People With Diabetes
University of Michigan
Summary
Pre-diabetes (Pre-D) is a precursor to type 2 diabetes (T2D) and characterized by increased exercise fatigability of lower limb muscles, that can impede exercise performance. The cause for the increased fatigability in people with Pre-D is not known. Given the profound vascular disease present in people who have had uncontrolled diabetes for several years, we will determine whether dynamic, fatiguing contractions of the lower limb muscles in people with Pre-D are limited by vascular dysfunction at multiple levels along the vascular tree including the artery, arteriole, and/or capillary. This clinical trial involves a novel exercise training regime involving blood flow restriction to the exercising limb will be used as a probe to further understand the vascular mechanisms for increased fatigability in people with Pre-D and T2D. The long-term goal is to better understand what limits exercise and functional performance in people with diabetes to help develop targeted, more effective exercise programs.
Description
The aim of the clinical trial is to determine the effectiveness of dynamic resistance exercise training coupled with blood flow restriction to improve fatigability and vascular function in people with Pre-D and T2D. People with Pre-D and T2D from Aim 1 will perform 8 weeks of dynamic unilateral resistance exercise training in which one leg is exercised with freely perfused conditions and the other leg with blood flow restriction. We will assess fatigability, skeletal muscle metabolism, capillary density, and vascular function in people with Pre-D and T2D before and after a novel training inte…
Eligibility
- Age range
- 30–85 years
- Sex
- All
- Healthy volunteers
- No
Inclusion Criteria: * Men and women adults 30 years to 85 years or less * Pre-diabetes \[glycosylated hemoglobin (HbA1c) of 5.7-6.4% and fasting plasma glucose 100-125 mg/dL at the time of initial screening\] * Controls \[normoglycemic with a HbA1c level ≤5.6% and fasting blood glucose ≤ 99 mg/dL (5.5 mmol/L)\] * Type 2 Diabetes Mellitus \[elevated glycosylated hemoglobin (HbA1c) \>6.5% and \<10%\] Exclusion Criteria: * Signs or symptoms of neuropathy * Medications associated with advanced stages of T2D including insulin * Poor glycemic control (HbA1c\>10%) * Peripheral edema * Severe obesi…
Interventions
- OtherControl Exercise
Each participant will attend 3 sessions per week for 8 weeks. Participants will perform low-load knee extension resistance training (20% of 1-RM) without blood flow restriction on the designated leg for 4 sets of contractions with 15 contractions per set of contractions with a 30 second rest between each set of contractions.
- OtherBlood Flow Restriction Exercise
Each participant will attend 3 sessions per week for 8 weeks. Participants will perform low-load knee extension resistance training (20% of 1-RM) with blood flow restriction on the designated leg for 4 sets of contractions with 15 contractions per set of contractions with a 30 second rest between each set of contractions.
Location
- University of MichiganAnn Arbor, Michigan