VSTC Lab FAQ

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Where is the GWU Weight Management and Human Performance Laboratory facility located?

GW has two fitness testing facilities: one located in DC near the Foggy Bottom Campus called the Exercise Physiology Lab, and one located on the Virginia Science and Technology Campus (VSTC) called the the GWU Weight Management and Human Performance Lab.  The  GWU Weight Management and Human Performance Lab on the VSTC campus is just off of route 7, near the intersection of RT 7 and Loudoun County Parkway.  The address is:

Enterprise Hall, room B25
44983 Knoll Square

Ashburn, VA 20147

Enter through the rear of the building (the side facing Route 7).  Security will buzz you in, and you’ll need to sign in and present a photo ID.  Proceed straight back toward the large portrait of George Washington; turn right, and the lab is the 2nd door on the left.   Parking is free on the VSTC campus.

What is the difference between all the different types of body composition tests? Which one is best?

All of our body composition assessments are non-invasive and similarly accurate. Historically, hydrostatic (underwater) weighing was considered to be the "gold standard" for body composition.  However, Dual Energy X-ray Absorptiometry (DXA) is now considered to be the most accurate means for assessing body composition.  Major advantages of DXA are that it also measures bone density, and the iDXA used in our lab also can measure the amount of visceral fat surrounding the organs.  We also use the InBody 720 to measure bodyfat.  This device uses multifrequency bioelectrical impedance, and does not rely on empirical prediction equations to determine bodyfat.  As a result, it very accurate; nearly identical to the iDXA.  However, the InBody 720 is not capable of measuring visceral fat. 

Example of an InBody Report

Example of an iDXA Report

What should I wear?

Some assessments have certain clothing restrictions. See below for details. For your convenience we have changing room and lockers.

DXA: This test can be performed fully clothed and with shoes one.  Any normal clothing can be worn, but large metal objects such as buckles should be removed prior to the test. 

Maximal/Submaximal Graded Exercise Test: Please come prepared with appropriate athletic clothing and shoes. We recommend shorts and a T-shirt for maximum comfort while exercising, because you may become warm and cannot remove layers once testing has begun.

BIA:  You will need to be barefoot during this test.  Please wear lightweight clothing to ensure test accuracy.  You will also be asked to remove all jewelry and metal during this test.  People with pacemakers or implanted electrical devices will not be permitted to take this test.

Am I allowed to exercise on the day of, or prior to testing?

In general, we recommend that you abstain from vigorous exercise for 12-24 hours prior to testing. Please be sure to properly hydrate during and after exercise, especially if you are coming in for a Bioelectrical Impedance Analysis.

For any exercise or performance test, aerobic or anaerobic, we also advise that you refrain from strenuous exercise for a few days before your test, just enough to ensure that you are properly rested.

How long must I wait after eating or drinking before testing?

It is not necessary to do an extended fast before any procedures, but please refrain from eating or drinking for at least two hours before coming in (4 hours for an RMR test). Also avoid caffeine on the day of any body composition assessment. For maximal exercise tests, we do not recommend consuming a large meal beforehand, but rather a light, healthy snack (i.e. ~200 calories, with carbohydrates and protein) two hours before exercise.

What is the difference between total fat mass, total fat-free mass, and percent body fat?

Fat mass is the absolute amount of body fat, measured in pounds or kilograms. Fat-free mass or lean mass is any tissue or part of the body that does not contain fat, such as skeletal muscle, bones, and water. Body fat percentage ratio of total weight of fat to the total weight of the body.

Do you offer any packages or discounts for multiple assessments?

Yes, we offer several packages to meet your needs. We also offer a "track your progress" plan, which gives users a 20% discount for every test purchased after the first. You must pay up front for all assessments and you will receive a voucher for any test you wish to do at a later date, valid for one year. This option is great if you are beginning a diet or fitness routine and would like to compare "before" and "after" information. 

What forms of payment do you accept?

We accept cash and checks made payable to The George Washington University, as well as Visa, MasterCard, and Discover. We do not accept insurance, but you may contact your provider directly to ask if they may reimburse you for some services.

Is there parking available?

Free parking is available on the VSTC campus.