The purpose of this study is to examine the effects of treadmill training on inflammation in the skeletal muscle and adipose tissue, insulin action in the skeletal muscle, and whole body glucose metabolism in stroke survivors. The fundamental hypothesis of this study is that key inflammatory markers in adipose tissue and skeletal muscle are abnormal, skeletal muscle insulin signaling is impaired, and systemic insulin sensitivity is reduced in hemiparetic stroke patients and that these factors are modifiable and improved by exercise training in stroke patients.
Many stroke survivors are sedentary and are at risk for the development of diabetes. We will study the interactions of adipose tissue and the paretic and non-paretic muscle inflammation, insulin signaling and action in hemiparetic stroke patients and the ability to employ exercise training to reverse these abnormalities in this ethnically diverse population. Participants aged 40-75 years with chronic stroke will be randomized to treadmill training versus stretch control group using a one-two-one blocked randomization on race (black vs. white), sex (male vs. female), and glucose tolerance status (normal vs. impaired and type 2 diabetes).
Stroke occurs in over 780,000 persons each year in the U.S., the vast majority reported in persons older than 55 years of age. Following stroke, patients remain at continued high risk for recurrent stroke. Inflammatory processes lead to cardiovascular events/stroke and contribute to disease risk progression by impacting insulin resistance and the development of type 2 diabetes. Interventions that reduce inflammation and improve insulin sensitivity have important clinical implications, especially in the stroke population.
Task-oriented treadmill training is utilized to improve cardiovascular fitness and functional mobility in hemiparetic stroke patients. Additionally, preliminary data indicates that progressive treadmill training in this population improves glucose tolerance.
- Aerobic Exercise Other
Intervention Desc: Treadmill training- begins at 15 minutes total duration at 40-50% maximal heart rate reserve 3 times per week, increasing to 60-70% maximal heart rate reserve for 45-60 minutes for 6 months ARM 1: Kind: Experimental Label: 1 Description: Treadmill ARM 2: Kind: Experimental Label: Aerobic Exercise Description: Treadmill training
- Stretching Behavioral
Intervention Desc: Stretching, balance exercises, and components of conventional physical therapy-- begins at 15 minutes and progresses to 45 minutes for 6 months ARM 1: Kind: Experimental Label: 2 Description: Stretch ARM 2: Kind: Experimental Label: Stretch Control Description: Stretching exercises
- Allocation: Randomized
- Masking: Open Label
- Purpose: Treatment
- Endpoint: Efficacy Study
- Intervention: Parallel Assignment
|Type||Measure||Time Frame||Safety Issue|
|Primary||TNFalpha (tumor necrosis factor alpha), adiponectin in adipose tissue and skeletal muscle||Baseline and 6 months||No|
|Primary||Whole body insulin sensitivity||Baseline and 6 months||No|
|Primary||VO2peak (maximal oxygen consumption)||Baseline and 6 months||No|
|Primary||Muscle insulin signaling proteins||Baseline and 6 months||No|
|Secondary||Circulating cytokines||Baseline and 6 months||No|
|Secondary||Glucose||Baseline and 6 months||No|
|Secondary||Insulin areas under the curve by Oral Glucose Tolerance Test||Baseline and 6 months||No|
|Secondary||Body composition (total body fat, visceral fat, subcutaneous abdominal fat, mid-thigh low density lean tissue)||Baseline and 6 months||No|
|Secondary||Muscle triglyceride content||Baseline and 6 months||No|
|Secondary||Number of macrophages||Baseline and 6 months||No|
|Primary||VO2peak||Baseline and 6 months|
|Secondary||Cytokines||Baseline and 6 months|
|Secondary||Body fat||Baseline and 6 months|
|Secondary||Muscle mass||Baseline and 6 months|