Chapter 8: Physiological Assessments Flashcards
signs that a client needs to stop assessment (10)
- onset of angina, chest pain, or angina-like symptoms
- significant drop (>10 mmHG) in systolic blood pressure despite an increase in exercise intensity
- excessive rise in blood pressure: SBP reaches >250mmHg or diastolic BP reaches >115mmHg
- excess fatigue, shortness of breath, or wheezing
- signs of poor perfusion: lightheadedness, pallor (pale skin), cyanosis (bluish coloration, especially around the mouth), nausea, or cold and clammy skin
- Increased nervous system symptoms (e.g. ataxia, dizziness, confusion, or syncope)
- Leg cramping or claudication
- subject requests to stop
- physical or verbal manifestations of sever fatigue
- failure of testing equipment
Bioelectrical impedance analysis (BIA)
Method: whole body BIA machines are primarily found in lab settings, less sophisticated ones are in gyms
Description: Measures electrical signals as they pass through fat, lean mass, and water in the body. essentially assesses leanness, but calculations can be made based on this info. The accuracy is based on the sophistication of the machine and the validity of the prediction algorithms. Many fitness centers use it due to the simplicity of use. Optimal hydration in necessary for accurate results
Air displacement plethysmography (ADP)
Method: example (Bod Pod), marketed for the fitness setting, but it’s cost prohibitive for most facilities
Description: The Bod Pod is an egg-shaped chamber that measures the amount of air that is displaced when a person sits in the machine. Two values are needed to determine body fat: air displacement and body weight. ADP is very accurate, but expensive
Dual-energy x-ray absorptiometry (DXA)
Method: typically found in clinical settings, may be found in exercise physiology departments at colleges and universities
Description: It ranks among the most accurate and precise methods. It’s a whole body scanning system that delivers a low dose x-ray that reads bone and soft-tissue mass. It has the ability to identify regional body-fat distribution
Hydrostatic weighing
Method: the gold standard- many methods of body-fat assessment are based on calculations derived from hydrostatic weighing, may be found in exercise physiology departments at colleges and universities
Description: measures the amount of water a person displaces when completely submerged, thereby indirectly measuring body fat via body density. It’s not practical in a fitness setting due to set up and such.
Near-Infrared interactance (NIR)
Method: example- Futrex
Description: Uses a fiber optic probe connected to a digital analyzer that indirectly measures tissue composition (fat and water). Typically, the biceps are the assessment site. Calculations are then plugged into an equation that includes height, weight, frame size, and level of activity. It’s inexpensive and fast, but not as accurate as other techniques.
Total body electrical conductivity (TOBEC)
Method: Found in clinical and research settings
Description: It uses an electromagnetic force field to assess relative body fat. It is impractical and too expensive for fitness settings.
1) Skinfold Assessment
2) Skinfold Assessment Sites
3) Protocol
1) General Info: most practical tool for measuring body composition, very commonly used in fitness settings,
2) Sites: skinfold calipers are used to “pinch” a fold of skin and fat (subcutaneous body fat). Several sites on the body are typically measured. It is reccommended that multiple sites are measured: FOR MEN-1. chest (a diagonal skin fold taken midway between crease of the underarm and the nipple), 2. Thigh (a vertical skin fold taken on the anterior midline of the thigh between the inguinal crease at the hip an the proximal border of the patella-top of knee), 3. abdominal (a vertical skin fold taken 2 cm or approximately 1 inch from the umbilicus-belly button). FOR WOMEN– 1. Tricep (a vertical fold on the posterior midline of the upper arm taken halfway between the shoulder and elbow) 2. Thigh (same as men’s) 3. Suprailium (a diagonal fold following the natural line of the iliac crest taken immediately superior to the crest of the ilium and in line with the anterior axillary line) The measurements are plugged into an equation that calculates body-fat percentage.
3. Protocol: 1. All measurements are taken on the right side of the body white client is standing 2. Sites should be marked with a pencil that can be washed off 3. thumb and index finger of left hand are opened to about 8cm or 3 inches and positioned about 1cm or 1/2 an inch above each site, pinch the site, pull the fat away from the tissue 4. calipers are placed 1 cm below thumb and midway between top and base of fold 5. slowly release caliper trigger, reading the dial to the nearest .5mm approximately 2 or three seconds after the release 6. After that is complete, gently squeeze the trigger to remove caliper before releasing the skin fold pinch (measure each site twice) 7. Record all measurements on a testing form *if measurements are reading a difference greater than 2mm, a third measurement must be taken, wait 20 to 30 seconds between each measurement for skin and fat to redistribute
Body mass index (BMI)
General Info: objective ratio describing the relationship between body weight and height, demonstrate strong correlations to morbidity and mortality, provide only estimations of body composition and fitness level
Protocol: BMI = Weight(kg)/Height^2(m) or Weight(lb)/Height^2(in) x703
*to convert pounds to kilograms, divide lbs by 2.2, to convert inches to cm to meters, multiply inches by 2.54, then divide by 100
Programming Considerations: it is important to explain the risks of being obese or overweight to a client…over 65% of Americans are overweight and 35.7% are obese, a BMI over 25 increases a person’s risk for cardiovascular disease, metabolic syndrome, hypertension, and type 2 diabetes
Girth measurements
General Info: good predictor of health problems (waist circumference as it correlates to heart disease) and it provides motivation as clients see changes in their body dimensions
Protocol: go through all the measurements in one rotation (Abdomen, waist, buttocks/hips, mid thigh, upper thigh, calf, arm, forearm), then do it again, if the difference is over 5mm, then remeasure after waiting 20-30 seconds
Waist-to-hip ratio
General Info: demonstrate strong correlations to morbidity and mortality, provide only estimations of body composition and fitness level, it also helps differentiate android (apple-shaped) individuals-carry more weight in the abdomen area- from gyroid (pear-shaped individuals)-carry more weight in the hips and thighs
Protocol: waist measurement is divided by hip measurement
Programming Considerations:
-Excellent/Good/Average/AtRisk WHR for men: .95
-Excellent/Good/Average/AtRisk WHR for women: .86
Equation for Skinfold Assessment (Body Density)
Calculation of Body Density:
MEN= 1.10938-0.008267 (sum of three skin folds) + 0.0000016 (sum of three skin folds ^2)- 0.0002574 (age)
WOMEN= 1.099421-0.0009929 (sum of three skin folds) + 0.0000023 (sum of three skin folds^2) - 0.0001392 (age)
General Body-Fat Percentage Categories for Women
Essential Fat: 10-13% Athletes: 14-20% Fitness: 21-24% Average: 25-31% Obese: 32% and higher
General Body-Fat Percentage Categories for Men
Essential Fat: 2-5% Athletes: 6-13% Fitness: 14-17% Average: 18-24% Obese: 25% and higher
Body Fat Equation (Part of Skinfold Assessment)
Siri equation (1961):
% Fat =
(495/Body Density)-450
Brozek et al. equation (1963):
% Fat =
(457/Body Density)-414
Programming Considerations: of Skinfold Assessment
Assessment is essential for a PT who is designing a personalized exercise program, especially if the primary goal is weight loss or weight gain. Reducing adipose tissue is also important for anyone trying to decrease the risk of disease or dysfunction. Programs should be partnered with evidence -based dietary recommendations. Note: With any weight loss or gain, there is typically a change in the amount of both lean body mass and fat mass