LABORATORY EXERCISE 2

RELATIONSHIP OF DYNAMIC STRENGTH TO SELECTED GIRTH MEASURES

Objective

        To determine if the strength of certain muscle groups may be predicted from girth measures.

Equipment

        Gulick tape

        Dumbbell with weights

        Universal or comparable leg press machine

Procedures

        1. The class will divide into groups of four:

             Subject

             Recorder

            Tester (2)

        2. Measure the girth of the biceps by use of the Gulick tape.  The biceps will be measured with the arm hanging at the side of the body.  The measurement will be taken relaxed at the point of greatest circumference between the elbow and the acromion process (Figure 1-2-1).

        The quadriceps circumference will be measured with the subject standing (non-flexed).  This measure will be taken between the knee and acetabulum at the point of greatest circumference (Figure 1-2-2).

Figure 1-2-1

Method of measuring girth of the biceps.

Figure 1-2-2

Method of measuring girth of the quadriceps.

        3. The measurement of dynamic strength will be done as follows:

            a. The biceps strength measurement will be taken using a dumbbell with the weights at 2.5 lb. increments.  The subject should hold the weights in a supinated position and have the elbow resting on the padded board.  Following a warm-up of 5-10 curls at 5.0 lbs., women will begin contractions through a full range of motion until the maximum strength is reached.  This will be accomplished using 1 R for each amount of weight added until the maximum is reached.  After 5-10 contractions at 20-30 lbs. men will do the same until the maximum strength is reached.  At least 1 minute of rest should be allowed between contractions.

            b. Quadriceps strength will be measured using the leg press on the Universal Gym.  Both male and female subjects should warm up before attemting maximum contractions.  Maximum strength measurement will be accomplished by having the subject complete 1 R at increasing weights until the maximum is reached.  At least 1 minute of rest should be allowed between contractions.

Results

1. Calculate the mean strength for men and women for both muscle groups.

2. Using the male data only, correlate the strength for the quadriceps with the quadriceps girth.

Conclusions

1. What is the relationship beteen girth measures and strength for the two muscle groups?  Can you explain this?

2. What are the mean differences between males and females in strength measures?  Is this expected and why?

3. What are the problems associated with using girth measures to predict muscular strength.

Reproduced from:

Vaughn, C., & Johnson, R. (1984). Laboratory experiments in exercise physiology: Measurement / evaluation / application (pp. 14-17). Dubuque, IA: Eddie Bowers Publishing Company. Copyright Ⓒ 1984, by eddie bowers publishing company