Barriers to Physical Activity in People With Type 2 Diabetes (Rxercise)

This study is currently recruiting participants.
Verified October 2012 by University of Colorado, Denver
Sponsor:
Collaborator:
Colorado Clinical & Translational Sciences Institute
Information provided by (Responsible Party):
University of Colorado, Denver
ClinicalTrials.gov Identifier:
NCT01701570
First received: June 13, 2012
Last updated: January 8, 2013
Last verified: October 2012
  Purpose

The investigators plan to learn more about how different levels of exercise feel to people with Type 2 Diabetes and how it feels to people without Type 2 Diabetes. This study team will also look at what causes exercise to feel harder or easier to people with and without Type 2 Diabetes. The investigators will also compare the potential benefits of supervised exercise training to that of diabetes education/blood sugar monitoring.


Condition Intervention
Type 2 Diabetes
Behavioral: Placebo Attention Control
Other: Supervised Exercise Training

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Mediators of Perceived Exercise Effort in Type 2 Diabetes - Barriers to Physical Activity

Resource links provided by NLM:


Further study details as provided by University of Colorado, Denver:

Primary Outcome Measures:
  • Rating of perceived exercise effort (RPE) during exercise (Borg RPE scale) [ Time Frame: Baseline, week 20 ] [ Designated as safety issue: No ]
    RPE was developed by Dr. Gunnar Borg and is a validated, self-reported measure of perceived effort during exercise. Possible scores range from 6 (no effort, resting) to 20 (maximal effort). Change = RPE post-intervention (week 20) - RPE baseline.


Secondary Outcome Measures:
  • Serum lactate during exercise [ Time Frame: Baseline, week 20 ] [ Designated as safety issue: No ]
    Serum lactate is measured by the University of Colorado clinical laboratory (Units = mg/dl).


Estimated Enrollment: 150
Study Start Date: April 2012
Estimated Study Completion Date: September 2014
Estimated Primary Completion Date: September 2014 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: 25 Participants with Type 2 Diabetes Other: Supervised Exercise Training
The 20-week aerobic exercise training intervention provides supervised exercise training sessions 3 times weekly following the HERITAGE study training model that was feasible in prior studies with older, sedentary overweight adults (55%maximal oxygen uptake (VO2max) for 30 minutes per session at study entry with progressive titration to 70-80% VO2max for 50 minutes).
Placebo Comparator: 25 Participant with Type 2 Diabetes Behavioral: Placebo Attention Control
The placebo attention control group will receive weekly phone calls to monitor their blood glucose levels.

Detailed Description:

Exercise is a potent therapy to reduce cardiovascular mortality in Type 2 Diabetes (T2D). Although exercise is a cornerstone of treatment for T2D, people with T2D are more sedentary than similarly obese people without diabetes, for reasons that are unclear. Interventions which combined behavioral support and physical activity prescriptions successfully increased physical activity levels for people with T2D and at-risk for T2D. However, the program components which mediated increased physical activity were combined and thus the individual benefits of each component remain unknown. Given the success of these combined programs, it appears behavioral support and other psychological factors may play an important role. The study investigators are interested in the predictors of physical activity adherence in T2D as key targets for future interventions.

One likely factor which may influence physical activity adherence is perceived exercise effort. The study investigators reported, based on a small study, that perceived exercise effort is worse in people with T2D than in healthy obese controls, as measured by the Borg Rating of Perceived Exertion (RPE), even during low intensity exercise. Thus, one strategy to increase physical activity in T2D is to first identify the mediators of RPE in the proposed study and then to address them in future studies. The preliminary data suggest that likely mediators of RPE are both objective and subjective in nature. A key objective mediator of RPE is serum lactate level during exercise, which is a physiological marker of effort, and is disproportionately elevated in people with T2D vs. healthy controls. A key subjective mediator of RPE is self-efficacy, which influences the perception of exercise effort, and is disproportionately worse in people with T2D vs. healthy controls. To develop optimal physical activity interventions for people with T2D, the study investigators must understand whether RPE differences vary across the spectrum of exercise intensities (Aim 1), and the investigators must also determine the mediators of RPE across exercise intensities (Aim 2). Mediators of RPE in low-to-moderate intensity exercise are particularly important, because walking is a preferred physical activity for people with T2D.

  Eligibility

Ages Eligible for Study:   50 Years to 70 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Sedentary men and women not participating in a regular exercise program (> 60 minutes of exercise per week)
  • If subject has diabetes, must be uncomplicated type 2 diabetes (T2D) and <15 years since T2D diagnosis
  • Ages of 50-70 years
  • BMI between 25 and 35
  • Subjects can only be taking the following oral hypoglycemic drugs: metformin, sulfonylureas or sitagliptin. Use of insulin or other oral hypoglycemic medications is not allowed.
  • Persons with T2D will be accepted for study only if they have total glycosylated hemoglobin levels (HbA1C) <8.0% (adequate control) on therapy.
  • Control subjects must have HbA1C < 5.7% and a fasting blood glucose of <100 mg/dl suggesting no significant insulin resistance.
  • All women must be post-menopausal, documented by menstrual history and follicle stimulating hormone (FSH) level.
  • Current smokers will be excluded since smoking can impair cardiovascular (CV) exercise performance but people who have quit smoking for at least 1 year will be accepted for study.
  • Absence of comorbid conditions that could affect exercise will be confirmed by history, physical examination and laboratory testing.

Exclusion Criteria:

  • Persons with clinically evident distal symmetrical neuropathy, determined by evaluation of symptoms (numbness, paresthesia) and signs (elicited by vibration, pinprick, light touch, ankle jerks), will be excluded from further study as neuropathy may limit exercise performance. Specifically, if monofilament sensation is absent at the level of the ankles, then participants will be excluded from study participation.
  • Persons with autonomic dysfunction (>20 mm fall in upright BP without a change in heart rate) will be excluded as well, due to associated limitations of exercise performance.
  • Persons will be excluded if they have evidence of heart disease by history (Prior heart attack or bypass surgery, heart failure, or significant valvular disease) or abnormal resting electrocardiogram (EKG) consistent with prior infarct or latent ischemia (unless cardiovascular stress imaging or catheterization shows they do not have coronary artery disease). The investigators will also exclude subjects with left or right bundle branch block on resting EKG (precludes recognition of ischemic EKG changes with exercise) or abnormal exercise EKG (> 1 mm ST segment depression 80 msec out in the ST segment for 3 consecutive beats).
  • Persons with angina or any other exercise-limiting cardiovascular, pulmonary or musculoskeletal symptoms will be excluded as well.
  • Presence of systolic blood pressure >145 mm Hg at rest or >250 mm Hg with exercise or diastolic pressure >90 mm Hg at rest or >115 mm Hg with exercise are also grounds for exclusion.
  • Subjects with proteinuria (urine protein >220 mg/dl) or a creatinine > 1.6 mg/dl, suggestive of renal disease will be excluded.
  • Subjects with total cholesterol >220 mg/dl, low density lipoprotein > 130 mg/dl, or triglycerides > 250 mg/dl will be excluded given the potential insulin resistance and endothelial dysfunction associated with these cholesterol parameters.
  • Subjects taking the following medications will be excluded: insulin, oral hypoglycemic agents other than those stated in inclusion criteria.
  • Control subjects who have more than two immediate family members with type 2 diabetes will be excluded.
  • Subjects will be excluded for chronic obstructive pulmonary disease demonstrated by a ratio of Forced Expiratory Volume in 1 second (FEV1)/Forced Vital Capacity (FVC) < 0.70 or FEV1 <70% predicted during spirometry.
  • Persons weighing more than 300 pounds will be excluded as this exceeds the weight capacity of our Dual Energy X-ray Absorptiometry device
  • Participants with moderate cognitive impairment (Folstein Mini-Mental Status Examination (MMSE) score <24).
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT01701570

Contacts
Contact: Leah Herlache, MS 720-848-6688 leah.herlache@ucdenver.edu
Contact: Amy Huebschmann, MD 303-724-2268 amy.huebschmann@ucdenver.edu

Locations
United States, Colorado
University of Colorado, Anschutz Medical Campus Recruiting
Aurora, Colorado, United States, 80045
Principal Investigator: Amy Huebschmann, MD         
Sponsors and Collaborators
University of Colorado, Denver
Colorado Clinical & Translational Sciences Institute
Investigators
Principal Investigator: Amy Huebschmann, MD University of Colorado, Denver
  More Information

No publications provided

Responsible Party: University of Colorado, Denver
ClinicalTrials.gov Identifier: NCT01701570     History of Changes
Other Study ID Numbers: 11-0909, 6147
Study First Received: June 13, 2012
Last Updated: January 8, 2013
Health Authority: United States: Institutional Review Board

Keywords provided by University of Colorado, Denver:
Type 2 Diabetes
Exercise
Rate of Perceived Exertion

Additional relevant MeSH terms:
Diabetes Mellitus
Diabetes Mellitus, Type 2
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases

ClinicalTrials.gov processed this record on April 15, 2014