The Human Performance Laboratory at St. Jude Children’s Research Hospital occupies 500 square feet in the Ambulatory Care Unit located next to the After Completion of Therapy Clinic. It is equipped with a Biodex System III Isokinetic Strength Testing System, a Smart Equitest with ten foot dual force plates and surface EMG monitoring capability. It is also equipped with Treadmill and Cycle Ergometers, a MedGraphics V02000 portable metabolic cart and a MedGraphics Cardioperfect ECG System. Hand held dynamometry, myometry, range of motion, flexibility, and sensory testing equipment are also available. The lab is staffed with a physical therapist and two full time exercise physiologists.
Anthropometrics (Body Size and Composition)
Sitting and standing height is measured with the shoes off using an electronic stadiometer Length is measured in children too young to stand, or in individuals who can not stand, while the person is lying on their back.
Weight is measured with an electronic scale.
Circumference measures of any body segment are available. All circumference measures are completed using a cloth tape measure with a built-in tension gauge to standardize compression of skin and underlying tissue. Measures are performed in duplicate to improve accuracy. Waist, hip, and head circumference measures are routine. The waist circumference is measured by taking the narrowest point between the xiphoid process and the umbilicus. The hip circumference is measured at the maximal circumference just below the gluteal fold. The head circumference is measured above the eyebrows and ears and around the back of the head. Waist to hip ratio is found by dividing waist circumference by hip circumference. Waist circumference can be interpreted as a standalone measurement.
Body fat measurements are taken using skin fold calipers.
Arm span is the distance between the tips of the fingers when the arms are stretched all the way out to the sides.
Chest wall excursion evaluates the amount of available movement in the chest wall. Circumferential measurements are taken at the bottom of the chest and under the arms during a maximal inspiration (big breath) and during a maximal expiration (after exhaling the big breath).
Range of Motion
Range of motion is measured using a goniometer, a device that indicates the degrees of movement available in a particular joint. Both active and passive motions are evaluated. Good range of motion is needed for both individual joint and total body movements.
The sit and reach is a test to measure hip, low back and hamstring flexibility. The test is performed while sitting on the floor with shoes removed and feet placed against the sit and reach box. The person being tested reaches forward with both hands as far as possible.
Mobility, Balance, and Motor Performance
The Timed-Up and Go is a measure of mobility. The individual is asked to rise from a seated position, walk ten feet, turn and return to the chair. The time to do this task is recorded and can be compared to published values.
Balance is evaluated in the SMART EquiTest® with Computerized Dynamic Posturography. The ability of the individual to maintain an upright position while responding to a variety of inputs to the eyes, the inner ear and the sensory organs of the legs and feet are tested.
The System utilizes a dynamic 18"x18" dual force plate with rotation and translation capabilities to measure the vertical forces exerted by the patient's feet; and a moveable visual surround.
The physical performance test assesses physical function in tasks that simulate activities of daily living among adults. The test consists of nine subsets: writing, eating, lifting, dressing, bending, turning, walking, and stair climbing.
The Bruininks-Oseretsky Test of Motor Proficiency, Second Edition (BOT-2) is an individually administered test that uses engaging, goal-directed activities to measure a wide array of motor skills in individuals aged 4 through 21. It provides a reliable and efficient measure of fine and gross motor control skills.
The Composite Cerebellar Functional Severity Score (CCFS) assesses cerebellar function. It includes the nine-hole peg and the click tests. For the peg test, the individual is seated holding nine dowels in one hand. The participant places them, one by one, with the opposite hand, in a board with nine holes. The time is recorded. For the click test, the participant is seated in front of 2 mechanical counters on a wooden board 39 cm apart. They use their index finger to press the buttons on the counters alternately 10 times each. The time is recorded.
Peripheral sensation is evaluated with the modified Total Neuropathy Score. This tool was developed to evaluate peripheral neuropathy in individuals following administration of neurotoxic chemotherapy agents. It includes participant reports of sensory and motor symptoms, and testing of pin sensibility, vibration thresholds, strength and deep tendon reflexes.
Muscle strength is measured with the Biodex System 3 Pro, a computer‑controlled dynamometer. This system has the capability to test muscle strength in a variety of modes, while the body part is moving and while it is held in a stationary position. The system tests most of the major joints and movements in the body. Speeds of movement, resistance, or limb positioning are modified depending on the needs of the research protocol.
Muscle strength can also be measured with more portable devices like a hand held dynamometer. In this photo, hand grip strength is measured using a hand-held dynamometer. The person is seated with the shoulder in a resting position and the elbow bent. The individual is asked to grip the device as hard as possible. The device records the force the person exerts while gripping the handle.
Portable myometers can also be used for other muscle groups in the body. Typically, the examiner will place the limb to be tested in a stationary position and have the participant push against the myometer. The tester applies force to the myometer until the participant can no longer resist the force.
Vital Sign Measurement
Heart rate is the number of times the heart beats per minute. It is evaluated by taking a “pulse” at the wrist or in the neck.
Blood pressure is the force applied by blood against the walls of blood vessels as the heart contracts. It is expressed in millimeters of mercury and measured by a sphygmomanometer (blood pressure cuff). The top number is called systolic blood pressure and the bottom number diastolic blood pressure. The top number is the force exerted on the vessels during a heart beat. The bottom number is the force exerted on the vessels between heart beats.
24-hour sampling provides a comprehensive assessment of blood pressure. This assessment is completed utilizing the Oscar 2™ system from Sun Tech Medical.
Respiratory rate is the number of breaths, or how many times the chest rises, in one minute.
Cardio Respiratory Fitness Evaluation
Resting and Stress Testing Protocols
Resting and stress testing protocols are available to evaluate function of the heart and lungs. These tests are done with equipment combinations that evaluate many physiologic variables. Both resting and exercise electrocardiograms are monitored using Medgraphics® Cardioperfect system. Breath-by-breath analysis of metabolic by products is completed using the Medgraphics® V02000 metabolic system and Breeze suite software. Results include metabolic rates and oxygen consumption. Blood pressure is monitored during testing by the Tango automated blood pressure monitoring system.
Stress Testing Protocols
Both sub maximal and maximal exertion test protocols are available depending on the needs of the protocol and on the health/fitness/disease status of the participants. Tests are done on an arm or leg cycle or on a treadmill.
- 12-lead resting ECG
- Resting metabolic rate
The six-minute walk is self-paced and is a measure of functional exercise capacity. This test measures the distance that a patient or participant can quickly walk on a flat, hard surface in a period of 6 minutes.
The electrocardiogram (ECG) evaluates the internal electrical pathway of the heart. ECG monitors heart rate and rhythm. It is done at rest, before, during and after cardiac stress testing. A normal ECG pattern is made up of a P wave, QRS complex, and a T-wave.
Habitual Physical Assessment
Physical activity is measured by having participants complete 2 components of the National Health and Nutrition Examination Survey.
- Physical activity and physical fitness questionnaire: This questionnaire asks questions about usual daily activities, leisure time activities, and sedentary activities at home.
- Physical activity monitor component: The PAM component allows collection of information on intensity and duration of common locomotion activities such as walking and jogging by having participants wear an activity monitor for seven consecutive days. Participants receive the accelerometer with instructions. The device is programmed to detect and record magnitude of acceleration or “intensity” of movement. An elastic belt with an adjustable Velcro closure and/or a belt clip is provided with each monitor. Participants are instructed to wear the monitor at the right hip during waking hours.