Chapter 6: Resistance Exercise for Impaired Muscle Performance

Endurance

Ability to perform repetitive or sustained activities for a prolonged period

Open Kinetic Chain

• Distal segment is free • Does not prepare for weight-bearing activities

Exercise order

• Large muscle groups before small • Multi-joint before single-joint • High intensity before low

Skeletal muscle adaptations to resistance exercise

• Related to the physiological cross-sectional area of the individual muscle fibers • Hypertrophy • Hyperplasia • Muscle fiber type adaptation

Closed Kinetic Chain

• The distal segment is fixed • The body moves over a fixed segment in a predictable pattern • Some degree of weight-bearing

Volume

Reps, sets, frequency

Velocity of exercise

Significantly affects the tension that the muscle produces and subsequently affects muscular strength and power.

Transfer of training

Strengthening on side in attempt for the other side to fellow

Intensity

The amount of external resistance imposed on the muscle

Strength

The force producing capacity of the muscle (Functional strength)

Reversibility Principle

The physical benefits of exercise are lost through disuse or inactivity. (use it or loose it.)

Power

The rate of performing work (Anaerobic and aerobic)

Progressive resistance exercise (PRE)

The type of physical activity done with the intent of improving muscle fitness.

Overload principle

To improve muscle performance there must be challenge to perform at a greater level

Substitute motions

using other muscles to perform the work due to the muscle being weak or too much resistance

Integration of function

• Balance of stability and active mobility • Balance of strength, power, and endurance • Task-specific movement patterns with resistance exercise

Stabilization

• External can occur by means of manual or equipment • Internal occur through isometric contraction of adjacent muscle groups

Goals for resistive exercise

• Increase strength • Increase endurance • Increase power

Rationale for use of open and closed kinetic chain exercise

• Isolation of muscle groups (open) • Control of movements (open) • Joint approximation (closed) • Co-activation and dynamic stabilization (closed) • Proprioception, kinesthesia, neuromuscular control, and balance (closed) • Carryover to function and injury prevention (open and closed)

Types of isometric exercises

• Muscle-setting exercises • Stabilization exercises • Multiple-angle isometrics

Circuit weight training (CWT)

• Pre-established sequence or circuit of exercises targeting major muscle groups is performed in succession at individual exercise stations • Total body conditioning and fitness • Variety of exercises

Form of exercise

• Type of muscle contraction (static or dynamic) • Position for exercise: Weight-bearing or nonweight-bearing • Forms of resistance • Energy systems (Anaerobic vs Aerobic) • Range of movement: Short-arc or full-arc exercise • Mode of exercise and application to function

Rationale and Indications for Isometric Exercise

•To minimize muscle atrophy • To begin re-establishing neuromuscular control of healing tissues • To develop postural or joint stability • To improve muscle strength when use of dynamic resistance exercise could compromise joint integrity or cause joint pain • To develop static muscle strength at particular points in the ROM consistent with specific task-related needs

Guidelines and special considerations for manual resistance exercise

- Body mechanics of the therapist - Application of manual resistance and stabilization - Verbal commands - Number of repetitions and sets/rest intervals

Factors that influence tension generation in normal skeletal muscle

- Energy stores and blood supply - Recovery from exercise - Fatigue • Muscle (local) fatigue • Cardiopulmonary (general) fatigue • Threshold for fatigue - Age • Early childhood and preadolescence • Adolescence • Young and middle adulthood • Late adulthood - Psychological and cognitive factors • Attention • Motivation and feedback

Type IIA muscle fibers

- Fast-twitch speed - High resistance to fatigue - Medium twitch force

Contraindications to Resistance Exercise

- Pain - Severe cardiopulmonary disease - Inflammation • Inflammatory neuromuscular disease • Inflammatory muscular disease • Acute joint inflammation

Reciprocal Exercise Equipment

- Stationary exercise cycles - Portable resistive reciprocal exercise units - Stair-stepping machines - Elliptical trainers and Cross-country ski machines - Upper extremity ergometers

Precautions for Resistance Exercise

- Valsalva maneuver (Holding Breath) - Substitute motions - Overtraining - Exercise-induced muscle soreness or DOMS

Physiological adaptations to resistance exercise

- Vascular and metabolic adaptations - Adaptations of connective tissues • Tendons, ligaments, and connective tissue in muscle • Bone mineral density

Type IIB muscle fibers

-strength and power -high intensities -low durations (creates significant hypertrophy)

Wolff's Law

A bone grows or remodels in response to forces or demands placed upon it

Manual Resistance Exercise

A form of active resistive exercise in which the resistance force is applied to either a dynamic or a static muscular contraction by the therapist

Specificity of training

A principle that training must be done with the specific muscle(s) the person is attempting to improve

Mechanical resistance

Active-resistive exercise applied externally by a machine or apparatus

Manual resistance

Active-resistive exercise applied externally by an individual

Determinants of Resistance Exercise

Alignment and stabilization

Resistive Exercise

Any active exercise in which a dynamic or static muscular contraction is resisted by an outside force

Hypertrophy

Increase in muscle fiber size

Hyperplasia

Increase in muscle fibers

Isometric exercise (static)

Muscle contracts and produces force without visible joint movement • Static control • Maintain posture • During immobilization