Effect of Regular Exercise on Vascular Function and Cardiovascular Risk in a Sedentary Work Force

NCT00246883 | Completed Phase 2

• 2 other identifiers: 06001806-H-0018
• Study Type: interventional
• Target: 120
• Locations: 1 country
• Sites: 1

Brief Summary

This study will evaluate the effects of NHLBI's employee exercise program, Keep the Beat, on blood vessel function. Damage to blood vessels can cause narrowing of the vessels, resulting in reduced blood flow to parts of the body such as the heart. Stem cells called endothelial progenitor cells, or EPCs, may be able to heal blood vessel damage. Exercise, such as walking on a treadmill, can help move EPCs from the bone marrow where they originate into the blood stream to help heal the damaged blood vessels. The Keep the Beat program encourages NHLBI employees to exercise 15 minutes during the workday and provides exercise facilities to accomplish this. NHLBI employees who have access to NIH exercise facilities may be eligible for this study. Candidates must have no history of heart disease, must not currently be exercising more than 1.5 hours per week and must not have participated in the Keep the Beat program for 3 months prior to entering the study. They are screened with blood tests and blood pressure measurements. Participants undergo the following tests and procedures before beginning the study and 3 months after participating in Keep the Beat:

• Blood tests to identify EPCs and their function, measure the level of nitric oxide (a gas produced by healthy blood vessels), and measure C-reactive protein (an inflammatory marker that may be a risk factor for cardiovascular disease).
• Brachial artery reactivity study to measure how well the arteries widen. An ultrasound device is placed over the subject's artery just above the elbow. The device measures the size of the artery and the flow of blood through it before and after a pressure cuff is inflated around the forearm.
• Treadmill exercise testing to evaluate physical fitness. Subjects exercise on a treadmill for as long as they can. An exercise specialist is present throughout the test. Heart rhythm and oxygen saturation are monitored continuously and blood pressure is measured every 3 minutes.

Conditions

Vascular Formation

Keywords

Endothelial Progenitor Cells; Nitric Oxide; Brachial Artery Reactivity; Physical Fitness; C-reactive Protein; Exercise; Vascular Function

Outcome Measures

Primary Outcomes (1)

• Improvement in brachial artery dilator responsiveness to shear stress as a bioassay for endothelium-dependent nitric oxide bioavailability following 3 months participation in the Keep the Beat program as compared with baseline measuraements.

Interventions

Exercise PROCEDURE

Eligibility Criteria

• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• Employees of NHLBI who are not currently participating in the Keep the Beat program (this may include employees who have previously registered for Keep the Beat program, but who have not participated in the past 3 months) and NIH employees who can use the excercise rooms in Building 10, Building 31, or Rockledge II.
• No medical condition that might prohibit safe participation in the Keep the Beat program.
• Subject understands protocol and provides written, informed consent in addition to willingness to comply with specified follow-up evaluations.

You may not qualify if:

• Heart disease as indicated by history of myocardial infarction, documented disease on coronary angiography, coronary artery stent placement, congestive heart failure, significant structural heart disease (e.g. hypertrophic or dilated cardiomyopathy, or valvular heart disease), or positive treadmill exercise test at baseline.
• Baseline blood pressure systolic greater than 140 mmHg or diastolic greater than 90 mmHg on 2 measures with or without hypertensive medications. Subjects will be encouraged to seek evaluation by their primary care provider.
• Baseline fasting blood glucose greater than 126 mg/dl, if subject previously undiagnosed as being diabetic. Subjects will be encouraged to seek evaluation by their primary care provider.
• Baseline fasting LDL greater than 190 mg/dl. Subjects will be encouraged to seek evaluation by their primary care provider.
• Physically unable to perform the Keep the Beat program due to neurologic or orthopedic conditions.
• Pregnant women will be excluded due to large hormonal changes in pregnancy that affect study variables and potential pregnancy-related restrictions on exercise.
• Subjects currently exercising more than 1.5 hours per week including brisk walking, sporting activities (such as basketball), and other deliberate exercise.
• Subjects may not be currently participating or participate over the course of the study in another study protocol which includes blood draws or interventions.

Sponsors & Collaborators

• National Heart, Lung, and Blood Institute (NHLBI): lead

Study Sites (1)

National Institutes of Health Clinical Center, 9000 Rockville Pike

Bethesda, Maryland, 20892, United States

Location

Related Publications (3)

• Blair SN, Kohl HW, Gordon NF, Paffenbarger RS Jr. How much physical activity is good for health? Annu Rev Public Health. 1992;13:99-126. doi: 10.1146/annurev.pu.13.050192.000531.

  PMID: 1599603 BACKGROUND

• Hu G, Tuomilehto J, Silventoinen K, Barengo NC, Peltonen M, Jousilahti P. The effects of physical activity and body mass index on cardiovascular, cancer and all-cause mortality among 47 212 middle-aged Finnish men and women. Int J Obes (Lond). 2005 Aug;29(8):894-902. doi: 10.1038/sj.ijo.0802870.

  PMID: 15724141 BACKGROUND

• Brownson RC, Boehmer TK, Luke DA. Declining rates of physical activity in the United States: what are the contributors? Annu Rev Public Health. 2005;26:421-43. doi: 10.1146/annurev.publhealth.26.021304.144437.

  PMID: 15760296 BACKGROUND

MeSH Terms

Conditions

Motor Activity

Interventions

Exercise

Condition Hierarchy (Ancestors)

Behavior

Intervention Hierarchy (Ancestors)

Motor Activity; Movement; Musculoskeletal Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena

Study Design

• Study Type: interventional
• Phase: phase 2
• Purpose: TREATMENT
• Sponsor Type: NIH

Study Record Dates

• First Submitted: October 29, 2005
• First Posted: October 31, 2005
• Study Start: October 26, 2005
• Study Completion: April 15, 2009
• Last Updated: July 2, 2017

Record last verified: 2009-04-15

Locations

US (1)