Chapter 13 Muscular Strength, Endurance, and Power.

Chapter 13

Muscular Strength, Endurance, and Power

Chapter ObjectivesAfter completing this chapter, you should be able to

1. Define muscular strength, dynamic strength, static strength, dynamic and static muscular endurance, and power.

2. State why muscular strength, endurance, and power should be measured.

3. Measure muscular strength, endurance, and power.

4. Describe responsibilities after the measurement of muscular strength, endurance, and power and

prescribe activities to improve muscular strength and endurance.

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Muscular strength is the ability of a muscle or muscle group to exert maximum force.

Dynamic strength is the force exerted by a muscle group as a body part moves (isotonic strength).

Static strength is the force exerted against an immovable object; movement takes not take place (isometric strength).

Both types of strengths are best measured by tests that require one maximum effort.

Muscular Strength, Dynamic Strength, and Static Strength

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Dynamic muscular endurance is the ability of a muscle or muscle group to resist fatigue and to make repeated contractions against a defined submaximal resistance

Static muscular endurance is the ability to maintain a certain degree of force over time.

High-resistance, low-repetition program or low-resistance, high-repetition program?

Must have some strength to develop endurance.

Dynamic and Static Muscular Endurance

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Muscular power is the ability to generate maximum force in the fastest possible time; ability to release maximum muscular force in an explosive manner.

Power equal to the product of force times velocity.

Force generated by muscular strength; velocity is the speed the force is used.

Power usually measured by some type of jump, throw, or charge (vertical jump, shop put, or a charge at a blocking sled).

Muscular Power

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Why Measure Muscular Strength, Endurance, and Power?

Muscular Strength1. Strong muscles help protect the joints; less

susceptible to sprains, strains, and other injuries.

2. Necessary for good posture (abdominal muscles, round shoulders, and low back pain).

3. Perform routine tasks more efficiently.

4. Increase changes for success in sports.

5.Decline in muscle strength can affect functions such as agility, balance, and coordination

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Why Measure Muscular Strength, Endurance, and Power?

Muscular Endurance1. Perform daily tasks better; prevent end-of-day fatigue.

2. Maintain good posture; decrease likelihood of back problems and muscular injury while performing routine tasks.

Muscular PowerOften a characteristic of a good athlete, but is rarely necessary for performing daily tasks.

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Responsibilities after Measurement

• Should seek to help individuals who need to improve

• Perform exercises on regular basis• Children usually do not need highly

organized program; use activities that require them to move and lift body

• Weight-training programs should be performed minimum of two days/week

• Exercises and guidelines are provided at conclusion of chapter

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Tests of Muscular Strength and Endurance

In laboratory and rehabilitation setting, dynamometers, cable tensiometers, and electromechanical instruments may be used to measure muscular strength and endurance.

Tests with Weight-Training EquipmentHandgrip, knee flexion, foot placement, and all other considerations that may influence test performance must be standardized.

Test must also be standardized for motivationalconsiderations.

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Conduct warm-up, avoid overworking, and observe safety precautions.

American College of Sports Medicine states:1.Participants should be familiarized with

equipment and test procedures.

2. All equipment should be tested for safety.

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ACSM (continued)3. Participants should be advised to exhale

during concentric contraction and inhale during eccentric contraction.

4. Adequate rest should be provided between tests.

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Dynamic strength measured with one repetition maximum(1-RM).

Relationship exists between body weight and weight lifted; maximum weight that can be lifted should be interpreted in relation to individual’s weight.

Major muscle groups may be tested with the bench press, standing press, arm curls, and leg press.

Table 13.1 reports optimal strength values for these lifts.


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Relative muscular endurance test - performer works with weight that is proportionate to the maximum strength of a particular muscle group or to body weight

Absolute muscular endurance test - all performers work with the same amount of weight (the weight has no relationship to maximum strength or body weight of the test performer)


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Tests of Muscular Strength and EnduranceIn a test for muscular endurance, weight should be lifted and returned without jerky movements.

A 3-second cadence may be used to encourage continuous, smooth movement.

A fixed percentage of 70% of the maximum strength may be used to test muscle endurance.

Health fitness – should be able to perform 12 to 15 repetitions of each of the lifts tested

Competitive athlete – should be able to perform 20 to 25 repetitions

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1-Repetition Maximum (RM) Bench Press Test

Test objective. Measure strength of arm extension muscles.

Age level. Twenty through sixty-plus.

Validity. Research shows 1-RM bench press is best weight lifting test for predicting total dynamic strength.

Norms. Table 13.2

Scoring. Ratio; divide maximum weight lifted by performer’s weight in pounds.

Free weight equipment preferred over Universal or Nautilus equipment.

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1-Repetition Maximum (RM) Leg Press Test

Test objective. Test strength of lower leg extension muscles.

Age level. Twenty through sixty-plus.

Face validity

Norms. Table13.3

Scoring. Ratio; divide maximum weight pressed by performer’s weight in pounds.

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YMCA Bench Press TestTest objective. Test dynamic muscle endurance of upper arm and shoulder girdle.

Age level. Eighteen through 65-plus.

Equipment. Metronone, 35-pound barbell, 80-pound barbell, and weight bench.

Norms. Table 13.4

Females use 35-pound barbell and males use 80-pound barbell.

30 repetitions per minute.

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Sit-Ups Test (Strength)

Test objective. To measure strength of abdominal and trunk flexion muscles

Age level. Twelve through college-age.

Face validity; reliability and objectivity coefficients reported.

Figure 13.1 illustrates the test.

Johnson and Nelson (1986) provide norms for college students.

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Sit-Ups Test (Endurance)Test objective. To measure abdominal strength and endurance

Age level. Five through adulthood.

Logical validity; reliability coefficient reported.

Three types of sit-ups tests may be administered – arms crossed on chest, hands interlocked behind neck, or hands cupped behind ears .

Figures 13.2 and 13.3 illustrate first two tests.

Tables 13.5, 13.6, and 13.7 report norms.13-19

Abdominal Curls

Test objective. To measure abdominal strength and endurance.

Age level. Five through adulthood.

Logical validity; reliability not reported.

Table 13.8 reports norms for ages eighteen through thirty.

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One Minute Curl Up TestTest objective. Measure abdominal strength and endurance.

Age level. Five through sixty-plus.

Face validity.

Administered in same way as abdominal curl except test performer’s feet are held in place.

Table 13.9 provides norms.

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Sit-ups and Curls-up Tests

• Sit-ups and curl-up tests described in this chapter emphasize speed of performance

• Similar tests described in chapter 15• Few of the tests in chapter 15 require test be

performed at a specified cadence• Some specialists believe speed incorporates

power; cadence procedure best measures muscular endurance

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Pull-Ups Test for Strength

Test objective. To measure arm and shoulder girdle strength.



Use weight plates and chair.

Johnson and Nelson provide norms for college males.

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Pull-Ups Test for Endurance

Test objective. To measure arm and shoulder girdle strength and endurance.

Age level. Nine through college-age.

Face validity; reliability coefficient reported.

Repeat pull-ups as many times as possible.

Table 13.10 reports norms for males, ages nine through seventeen-plus.

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Modified Pull-Ups for Endurance

Test objective. To measure arm and shoulder girdle endurance.

Age level. Ten through college-age.

Face validity; reliability not reported.

Figure 13.4 illustrates test.

No norms reported.

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Baumgartner Modified Pull-Ups Test

Test objective. To measure arm and shoulder girdle, endurance, or both.

Age level. Elementary through college.

Face validity and construct validity; reliability coefficient reported.


Table 13.11 reports norms for ages six through college-age.

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Modified Pull-Ups Test

Test objective. To measure upper body muscular strength and endurance.

Age level. Five through eighteen.

Figures 13.6a and 13.6b illustrate test.

No norms reported.

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Flexed-Arm Hang


Age level. Nine through college-age.


Table 13.12 reports female norms for ages nine through seventeen-plus.

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Dip Test for Strength

Test objective. To measure arm and shoulder girdle strength.



Johnson and Nelson (1986) provide norms for college males.

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Dips Test for Endurance


Age level. Ten through college-age.


No norms reported.

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Push-Ups


Age level. Ten through adulthood.

Face validity; reliability not reported; objectivity coefficient reported.

Table 13.13 reports norms for males ages twenty through sixty-nine.

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Modified Push-Ups


Age level. Ten through adulthood.



Table 13.13 reports norms for females ages twenty through sixty-nine; Canadian Physical Activity Fitness and Lifestyle Appraisal also includes norms.

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Tests of Muscular Power

Two types of muscular power may be measured : athletic power and work power.

Athletic power – distance the body or an object can be propelled through space

Work power – extraneous movements are controlled or eliminated, so that maximum effort must be put for by muscle groups being tested.

Only two athletic power tests presented.13-33

Vertical Jump

Test objective. To measure explosive leg power.

Age level. Nine through adulthood.

Validity, reliability, and objectivity coefficients reported.

Table 13.14 reports norms for ages ten through seventeen-plus and table 13.15 reports norms for ages twenty through fifty-nine.

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Standing Broad Jump

Test objective. To measure explosive leg power.

Age level. Six through college-age.


Table 13.16 reports norms for ages nine through seventeen-plus.

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Exercises to Develop Muscular Strength and Endurance

The following guidelines should be observed when performing exercises to develop muscular strength and endurance.

1. Perform stretching and warm-up exercises before attempting muscular effort.

2. Perform the exercises that provide a mild overload first and gradually progress to the more difficult ones.

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Guidelines (continued)

3. Unless otherwise indicated, begin with ten repetitions and add two or three repetitions each week until the desire number is reached.

4. Perform the exercises 3 to 5 days per week.

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Exercises to develop muscular strength and endurance are described in text. The exercises require no special equipment and can be performed by children and adults. The exercises are for the:

Posterior Upper Arms, Shoulders, Chest, and Upper Back

Anterior Upper Arms, Shoulders, Chest, and Upper Back

Abdomen; Lateral trunk; Lower Back and Buttocks; Lateral Hips and Thighs; Upper Legs; Lower Legs

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Chapter 13 Muscular Strength, Endurance, and Power.

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Transcript of Chapter 13 Muscular Strength, Endurance, and Power.