PEAK 404 EXERCISE PHYSIOLOGY LAB 5

Fitness Measures 1. Static Strength

Introduction Static strength refers to the ability of a muscle to generate maximal tension for a brief period of time under conditions of an isometric action (tension without a corresponding change in muscle length). The purpose of this lab is to indirectly predict overall muscular strength based on the handgrip strength. There are several specific physiological and anatomical rational, but, in general, the concept is that if a person can lift a heavy object, they must be also able to hold on to it in order to lift it. Handgrip strength is generally accepted as a good indicator of overall upper-body strength.

Lab Activity 1A. The device is a hand dynamometer (force measurer). The following are guidelines for performing this assessment correctly:

 Adjust the dynamometer so that the 2nd phalanx (middle bone of the finger) is bent approximately 90 degrees from the 1st phalanx (finger bone connected to the palm of the hand).  Stand with head facing forward and the forearm should be at an angle between 90 and 180 degrees to the upper arm, which is vertical (parallel to the side of the body).  Squeeze the dynamometer as hard as possible. Maximal force should be exerted as quickly as possible (apply force quickly; do not gradually build up force - your results will be lower). Record the reading from the dynamometer on the data form then reset it back to zero.  Repeat these steps for the opposite hand. Perform two to three trials, alternating hands. This is to allow for recovery of muscles for the next trial (recovery should be complete within 30 to 60 s).

2. Static Flexibility

Introduction Flexibility can be simply defined as range of motion about a joint. Flexibility can be classified in two ways: static flexibility and dynamic flexibility. Static flexibility is range of motion in a non-moving condition. Dynamic flexibility is range of motion while moving at various velocities, including high, sport-specific velocities. Many factors contribute to overall flexibility, including muscle extensibility, tendon and ligament stiffness, and joint anatomy. Also, flexibility is specific to the joint(s) at which it is measured. The sit-and reach-test and the modified sit-and-reach tests are general tests of static flexibility in the hamstring/low back area. Poor flexibility in this area is often associated with chronic low back pain, which can often be alleviated simply by improving flexibility. NOTE: sometimes low back pain is related to other causative factors such as poor abdominal/low back muscular strength and improper body mechanics while stationary and/or moving.

The modified sit-and-reach test is considered by many to be a better test of static flexibility in the hamstring/low back area. This test takes into account the initial reach measurement on the box with the legs straight and back flat against the wall. Flexibility measures are then taken with this initial reach point taken into consideration. Thus, this test takes into account varying limb length (i.e., long arms, short legs, etc.) that can affect the overall results of the test.

Lab Activity 2A. The following are guidelines for performing the modified sit-and-reach test correctly:

 Warming up prior to performing this assessment is recommended (walking/jogging in place, etc.) Place the feet (NO SHOES) against the sit-and-reach box, about shoulder width apart, with the scale facing up and toward the subject. The box should be supported from the rear to prevent it from sliding.  With the legs straight and the subject’s back and head against the wall, the subject reaches forward as far as possible with hands, one placed over the other with palms down and fingertips aligned at the ends (no reaching with one hand further than the other). NOTE: shoulder blades can be abducted as far as possible to extend the reach. The test administrator moves the reach indicator with the “L-shaped” moving indicator at the very end of the reach indicator. This identifies the initial reach point.  Now the subject is allowed to move the back and head off the wall, reaching forward as far as possible with both hands properly aligned, pushing the “L-shaped” indicator forward. Hold the distance reached for two seconds (NO BOUNCING). Repeat two times and record the greatest distance reached on the data sheet (usually the third trial). Use Scale B for measurements (this scale is in inches). Record your results on the data form. Using the percentile tables for static strength, find your percentile rank and include this information on the data form. Determine your flexibility classification based on the percentile rank tables. Record this information on the data form.

3. Estimation of VO2 max Introduction  Direct measurement of maximal oxygen consumption (VO 2max) is often impractical and  very challenging for the subject. Therefore, field tests have been designed to predict VO

2max. One chosen for this lab is the Forestry Step Test.

Lab Activity 3A. The Forestry Step Test requires the subject to step at 90 steps per minute for 5 minutes. At the end of 5 minutes a 15 second HR is measured and recorded. The pulse count is   compared to a table for estimation of VO 2max. The VO 2max max value is compared to a norm table to determine fitness level. Record this information on the data form.

4. Body Composition

Introduction The assessment of body composition (% body fat vs. % lean tissue) is a key component of overall fitness assessment related to general health and, in some cases, sport performance. There are a number of techniques for assessing body composition (refer to your textbook, chapter 18, pages 345-347 for a description of these techniques). This laboratory will provide experience with one relatively easy method for determining body composition: skinfold measurement. Skinfold measurement methods correlate well with the “gold standard,” which is currently hydrostatic (underwater) weighing.

Lab Activity 4A. The purpose of this portion of the lab is to estimate body composition using the method of skinfold measurement. Skinfold measures are used to predict body density, which is then used to estimate percent body fat. There are various equations for determining body density, many of which employ different measurement sites (ranging from 2 sites to 7 sites). This lab will utilize the often-used 3-site method for determining body density and subsequently, percent body fat.

The following are procedures for the correct measurement of skinfold thickness at the appropriate sites for the 3-site method:

Note: All measurements should be made on the right side of the body for standardization. Measure the sites for males and females as indicated below:

Skinfold Measurement Sites Men: chest, abdomen, thigh skinfold. Women: triceps, suprailium, thigh skinfold. Chest: a diagonal fold midway between the shoulder crease and the nipple. Abdomen: a vertical fold about one inch to the right of the umbilicus. Triceps: a vertical fold on the posterior upper arm, midway between the shoulder and elbow. Thigh: a vertical fold on the anterior thigh, midway between the knee and the hip. Suprailium: a diagonal fold above the right iliac crest.

1. Measure each site by grasping a skinfold (large as possible) with the thumb and forefinger, pulling the fold slightly away from the muscle tissue. The calipers are placed on the skinfold ½ inch away from the fingers. DO NOT RELEASE THE SKINFOLD WITH THE FINGERS. Allow the calipers to come to rest on the skinfold and the indicator to stop moving. Observe the reading on the caliper indicator. If the caliper indicator does not stop moving after three seconds, use the indicator reading at the three-second mark. 2. Measure each site once, and then repeat each set of measures twice more (do not measure the same site consecutively). 3. Determine the median reading for each site. Sum the three skinfold median measures ( SF). 4. Determine the body density (Db) and % body fat by using the following formulae:

Women: Db = 1.0994921  [0.0009929( SF)] + [0.0000023( SF)2]  [0.0001392(Age)]

Men: Db = 1.1093800 – [0.0008267( SF)] + [0.0000016( SF)2]– [0.0002574(Age)]

Next determine percent body fat (%BF) from the Siri equation:

%BF = ( 495 / Db) – 450

DATA FORM

1A. GRIP STRENGTH: Name Rt. Hand Lt. Hand SUM Percentile Percentile for (kg) (kg) (R + L) for Strength/Weight (kg) Strength (kg/kg))

2A. MODIFIED SIT-AND-REACH: Name Age / M or F Modified Flexibility Sit-&-Reach Category (inches)

 3A. Estimation of VO 2max – Forestry Step Test Name 15 sec HR  Fitness Estimated VO 2 (ml/kg/min) Category

4A. Body Composition Estimate Skinfold Chest or Abdomen Mid Sum % Body Fitness Measures Triceps or Thigh (mm) Fat Category (mm) (mm) Suprailium (mm) (mm) ( SF)

Fitness Category Excellent Good Acceptable Over fat Male 12% 13 – 17% 18 – 25% > 25% Female 16% 17 – 24% 25 – 30% > 30% PEAK 404 - LAB 5: Page 6

It is possible to calculate an estimate of ideal body weight when lean body weight and fat weight are known. The calculation for ideal body weight is, of course, not exact and is based on the difference in weight resulting from the reduction in only fat weight.

Fat Weight (FW) = Total Body Weight (TBW) x %Body Fat (BF)

Lean Body Weight (LBW) = TBW  FW

Ideal Body Weight (IBW) = LBW / (100%  Desired %BF)

TBW = ______

%BF = ______

FW = ______

LBW = ______

Desired %BF = ______

IBW = ______

LAB ASSIGNMENT (1) Generate one “presentation” table that includes all of your results (categories too). Include values generated from ideal body weight calculations. (2) How would you describe your fitness based on these measures? (refer to tables) (3) Do you agree with the results? Explain why or why not. (4) How could you change your current lifestyle to make improvements in each of these fitness categories? (5) What are the reasons you may have for maintaining your current fitness lifestyle? (6) What will be the likely result of you developing a lifestyle that makes these fitness categories worse?