Neuromuscular Training Foundations And Assessment

Foundations • Objectives of Resistance Training – Weight & Power Lifting – Bodybuilding – General Muscular Fitness – Rehabilitation – Sport Specific – Muscle physiology • Definitions of Muscular Function

Muscle Endurance

Muscle Endurance

is the ability of a muscle or muscle group to contract repeatedly or constantly against a resistance

Muscle Strength

Muscle Strength

is ability of a muscle or muscle group to exert maximal force against a resistance in a single repetition.

Muscular Power

Muscular Power

is the ability to exert force quickly; refers to the rate at which muscular force is applied.

Power

= Force x Velocity

Muscular Flexibility

Flexibility

refers to a joint’s range of motion (ROM).

Range of motion is dependent upon bony structure and “permissiveness” of muscle and tendons surrounding the joint

Type of Contraction Isotonic (DCER) Isokinetic Types of Contraction Type of Muscle Action Function Dynamic concentric Dynamic eccentric Dynamic isokinematic Acceleration Deceleration Acceleration or Deceleration Isometric Static Fixation

Types of Muscle Contraction • • •

Isometric:

static muscle contraction in which muscle tension develops but there is no change in joint angle.

Isokinetic:

dynamic muscle contraction in which limb displacement or joint rotation has a constant velocity.

Isotonic:

dynamic muscle contraction moving a constant external resistance.

Isotonic Contractions

Assessing Muscular Function Laboratory Methods Assessing Muscular Strength/ Endurance Laboratory and Field Methods Field Tests

Assessing Muscular Function • Laboratory Methods – Electromyography: measurement of neural or electrical activity that brings about muscle contraction – Isokinetic machines: measurement of torque throughout range of motion at controlled velocity – Force transducer: measure static strength and endurance

Assessing Muscular Function • Laboratory and Field Methods – Dynamometer: use a spring device – Constant Resistance Equipment: use 1 repetition maximum (1-RM) trial and error or 5-RM and 10-RM submaximal methods.

Assessing Muscular Function • Field Tests – Callisthenic Activities: relative strength or endurance – Vertical Jump/Standing Broad Jump: explosive leg power

Force: Velocity Relationship • Muscle’s force generating capacity declines with increasing shortening velocity.

• Conversely, as load increases, maximum shortening velocity decreases. • Greatest force (MVC) achieved @ zero velocity.

Power: Velocity Relationship • Peak power rapidly increases with increasing velocity up to peak velocity region.

• Thereafter, maximal power decreases due to reduction in max force at faster speeds.

• At any given velocity, greater power occurs in FT fibers than ST fibers.

Torque: ROM Relationship • Strongest biceps brachii angle seems to be 90°-130°.

• Amount of tension directly related to degree of overlap of thick and thin filaments in sarcomere.

• When muscle stretched, contact between actin & myosin crossbridge is poor, contraction weak.

Load: Repetition Relationship • Inverse relationship between load that can be lifted and number of repetitions that can be performed.

• Relationship for strength training zone 60 to 100% of 1 RM range.

100 95 90 85 80 75 70 65 60 55 50 1 2 3 4 6 8 10 12 14 15 Repetitions

Gender Differences • Women 50% less than men in absolute upper body strength.

• Women 25-30% less than men in absolute lower body strength.

Gender Differences • Women 5% to 15% weaker than men when expressed relative to body weight.

• No difference in strength when expressed in muscle cross-sectional area.

Children Weightlifting • Lifting weights in children has not been shown to prevent full growth of bones.

• Children who lift weights in supervised programs do not suffer more injuries than adults.

Giuliano

Illustration References • McArdle, William D., Frank I. Katch, and Victor L. Katch. 2011. Essentials of Exercise Physiology 4 th ed. Image Collection. Lippincott Williams & Wilkins.

• Plowman, Sharon A. and Denise L. Smith. 1998. Digital Image Archive for Exercise Physiology. Allyn & Bacon.

• Robergs, Robert A. and Steven J. Keteyian. 2000. Fundamental Principles of Exercise Physiology. McGraw Hill.