Therapeutic Exercise 2

Resistance Exercise-1

Dr. Dania Qutishat

Muscle performance

• Definition: “the capacity of the muscle to do work”.

• Factors that affect muscle performance: morphology of the muscle, neurological, biomechanical, biochemical factors, cardiovascular, respiratory, metabolic, cognitive and emotional function”.

• Important for functional movement.

Why it is important?

• To be to able to carry out the activities of daily living in a safe and efficient manner.

• The muscles has to produce, sustain ans regulate tension to carry out these functions.

Benefits of resistance Ex.

• Enhanced muscle performance.

• Increased strength of connective tissue.

• Increased mineral density of the bone.

• Decreased stress on joints during physical activity.

• Reduced risk of soft tissue injury during physical activity.

• Positive impact on tissue remodelling.

Benefits of resistance Ex.- Cont .

• Possible improvement in balance.

• Enhanced physical performance.

• Positive changes in body composition (less fat and more muscles).

• Enhanced feeling of physical wellbeing.

• Possible improvement of disability and quality of life.

Strength

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Strength

: “the greatest measurable force that can be exerted by a muscle or a muscle group to overcome resistance during a single maximum effort”.

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Functional strength

: the ability of the neuromuscular system to produce, reduce and control forces during functional activities in a smooth and coordinated manner”.

Power

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Def.

: “the rate at which the muscle contracts and produces a resultant force”.

• Single burst of high intensity.

• Repeated bursts of less intensity of muscle activity.

Endurance

• Endurance: “the ability of the muscle to contract repeatedly against a load, generate and sustain tension and resist fatigue over an extended period of time”.

• Cardiopulmonary (total body) Endurance refers to repeated and dynamic activities. • Aerobic power might be used interchangeably with muscle endurance.

• A strong muscle does not necessarily mean that it has endurance.

Strengthening Exercise

Systematic procedure of a muscle or group of muscles lifting, lowering or controlling heavy loads for low number of repetitions over a short period of time.

Power Exercise

• Exercises that increase the work performed by the muscle in a specified period of time OR reduce the amount of time needed to produce a given force.

Endurance Exercise

• Lifting or lowering light loads for many repetitions or sustain a muscle contraction for extended period of time .

• How does Strengthening ex. and endurance ex. affect the muscle performance positively?

Overload principle

• The resistance must be greater than the metabolic capacity of the muscle.

How to apply the overload principle in strengthening and endurance ex.?

SAID principle

• Specific adaptations to imposed demands.

• Specificity of the ex.: the exercise has to mimic the anticipated function.

How to make the resistance exercise specific?

Reversibility principle

• Adaptive changes in muscle performance following a resistance exercise are transient unless practiced regularly in functional activities or maintenance program of resistance exercises.

• Detraining starts within a week or two after cessation of the resistance exercise.

Determinants of resistance Ex .

1. Alignment: Positioning.

 Muscle action  Gravity 2. Stabilisation: holding the body segment steady  Internal stabilisation  External stabilisation To prevent substitute motions.

Substitute motions

• “Compensatory movement patterns caused by muscle action of a stronger adjacent agonist or a muscle group that normally serve as a stabilizer (fixator) ”.

Determinants of resistance Ex .

3. Intensity: amount of resistance (load).

 Submaximal loading  Maximal loading  Initial ex. loading  Repetition maximum  Alternative methods  Training zone

4. Volume  Repetitions number of muscle contractions performed to move the limb through a series of continuous excursion against a specific load.

 Training to increase strength Fatigue Ex causing (6-12 Repetitions for two or three sets).  Training to increase endurance (40, 50 or more Repetitions for 3-5 sets)

 Sets predetermined number of repetitions grouped together.

Rest after each set.

Determinants of resistance Ex.- Cont

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4. Ex order: the sequence in which exercises are being performed. Large muscles before small - Multi joint before single joint - Warm up, higher intensity then lower intensity ex.

Determinants of resistance Ex

 5. Frequency: number of ex sessions per day or per week.

Low intensity, Short sessions Daily basis, (several times per day).

- Increased intensity (every other day up to 5 days/week).

- Maintenance program (2 days/week) - Highly trained athletes high intensity (6 days/ week)

Determinants of resistance Ex

6. Duration: is the total number of weeks or months during which a resistance ex are being performed.   2-3 weeks- neural adaptation 6-12 weeks- hypertrophy and increased vascularisation.

Determinants of resistance Ex

6. Mode of Ex.: the form of ex.,, the manner in which the ex is carried out.  Type of muscle contraction - Isometric, Concentric, Eccentric  Position for Ex.

- Weight bearing, Non-weight bearing  Forms of resistance - Manual, mechanical/ Constant, variable load/ Accommodating resistance/ Body weight or partial body weight)

 Energy systems -Aerobic/Anaerobic  Range of movement - Short arc/ Full arc  Application to function.

Strengthening Exercise

7. Velocity  Force-velocity relationship Concentric vs. eccentric contraction.

8. Rest interval (recovery period):  Moderate intensity (2-3 minutes after each set).

 High intensity (4-5 minutes after each set).

 Pathological conditions, children and elderly (at least 3 minutes performing unresisted ex)

Factors that influence tension generation in normal skeletal muscle 1- Energy stores and blood supply 2- Fatigue 3- Recovery from exercise 4- Age 5- Physiological and cognitive factors

Energy stores and blood supply • Energy stores and blood supply Muscle needs energy to contract, generate tension and resist fatigue.

• Energy systems: - ATP-PC system - Anaerobic/ glycolytic/ lactic acid system - Aerobic system

Fatigue

• Muscle (local) fatigue • Cardiopulmonary (general) fatigue Definitions of fatigue are based on the type of fatigue.

Muscle (local) fatigue

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Definition

: ” Diminished response of muscle to a repeated stimulus ”.

• It is an acute and reversible physiological response to exercise. • Temporary state of exhaustion (failure) that result in decreased muscle strength.

Why it happens?

• Decrease in the energy stores, insufficient oxygen and build up of H+.

• Inhibitory influences from the central nervous system.

• Decrease in the conduction of impulses at the myoneural junction .

Types of muscle fibre

• Type I (tonic slow-twitch) Generates low level of tension that could be sustained for long period of time.

• Type II (phasic fast-twitch)- type IIA and IIB Generates great amount of tension in short period of time.

• Different muscle are composed of varying proportions of tonic and phasic fibres.

• High proportion of type I fibres- e.g. Postural muscles • High proportion of type IIB fibres- e.g. muscles responsible for lifting heavy loads.

Cardiopulmonary (general) fatigue • Definition: “Diminished response of the entire body as a result of prolonged physical activity ”.

• Why it happens?

- Decrease in the blood sugar (glucose) levels - Decrease in glycogen stores in the muscle and liver - Depletion of potassuim

Threshold for fatigue

• Definition: “ the level of exercise that cannot be sustained indefinitely”.

• Determined by: - Length of the muscle contraction - Number of repititions

Factors that influence fatigue

• Patients' health status.

• Diet.

• Lifestyle (active or sedentary).

• Patients with neuromuscular, cardiopulmonary, oncologic, inflammatory or psychological disorders- have abnormal onset of fatigue.

Recovery from exercise

– Intrasession and intersession recovery.

– Changes during recovery: Restore oxygen in muscles Restore energy Removal of lactic acid from skeletal muscle blood within 1 hour after exercise.

Replacement of glycogen over several days

Age

• • • • Infancy, early childhood and preadolescence Puberty Young and middle adulthood Late adulthood

Psychological and cognitive factors • Attention Ability to focus and learn • Motivation and feedback Effort and adherence over time Different types of feedback to enhance performance

Physiological adaptation to resistance exercise 1- Neural adaptation 2- Skeletal muscle adaptation 3- Vascular and metabolic adaptation 4- Connective tissue adaptation

Neural adaptation • First and rapid gain in the strength.

• Motor learning and improved coordination.

• Increased recruitment in the number of motor units firing.

• Increased rate and synchronization of firing.

• Decrease in the inhibitory function of the CNS.

Skeletal muscle adaptation

• Hypertrophy.

- Increase in the size of the individual muscle fibre.

- Occurs after moderate to high intensity resistance training (4-8 wks)/ 2-3 wks very high intensity resistance.

- Increase in the protein (myosin and actin) synthesis and decrease in protein degeneration.

Skeletal muscle adaptation

- High synthesis- moderate resistance, high volume, eccentric contraction.

- Muscle fibre type IIB- highest increase in size.

Skeletal muscle adaptation

• Hyperplasia - increase in the number of muscle fibres - Splitting fibres • Muscle fibre type adaptation - type II- hypertrophy - Transformation of IIB to IIA with endurance ex.

Vascular and metabolic adaptation • High intensity and low volume.

• Less capillary bed density because of the increased number of myofilaments per fibre.

• Decrease in the mitochondrial density.

• Reduced oxidative capacity of the muscle.

Connective tissue adaptation

• Tendons, ligaments and connective tissue in muscles.

- Increased strength of the tendons and ligaments which make them less prone to injury.

- Increased thickness of the connective tissue around the muscle fibers to support their increased size.

• Bone - High correlation between muscle strength and physical activity.

- ex performed from weight bearing positions to prevent or minimise bone loss

Types of resistance exercise

• Manual and mechanical resistance exercise.

• Isometric (static) exercise • Dynamic (concentric and eccentric) exercise • Dynamic exercise (constant and variable resistance) • Isokinetic resistance • Open-chain and closed chain exercise

Isometric resistance ex.

• Definition?

• Why? (rationale) • Types?

• Characteristics?

• Precaution and contraindication?

Concentric and eccentric ex.

• Definition?

• Why? (rationale) • Characteristics?

- Ex. load - Velocity - Energy expenditure - Mode specificity - Cross training effect - Ex. Induced muscle soreness

General principles of resistance training • Examination and evaluation (Health history, systems review, selected test and measurements) Determine a baselines of muscle performance (strength, endurance, ROM, functional activities). Why?

- Implement selected tests (examples?).

• Interpret the findings • Integrate the resistance ex. with the rehabilitation program.

Preparation for resistance ex .

• Select the form of resistance ex.

• Explain to the patient (understand and consent).

• The pt. should wear non restrictive clothing and a supportive shoes if needed.

• The supporting surface is firm but comfortable.

• Demonstrate each ex.

Application

• • • • • • • • • Warm up Placement of resistance Direction of resistance Stabilisation Amount of resistance Volume Instructions (verbal/written) Monitoring the pt Cool down

Precaution • Valsalva maneuver • Substitute motions • Over training and over work • Exercise induced muscle soreness • Pathological fracture

Contraindication • Pain • Inflammation • Severe cardiopulmonary disease

Advantages • Quantitative baseline measurement of muscle strength.

• Appropriate in moderate and advanced phases of rehabilitation (4/5).

• Training for already strong muscles.

• Increase in the level of resistance incrementally and quantitatively

Advantages

• Some equipment provide variable resistance.

• Some equipment provide high velocity exercise.

• Could be applied independently.

Disadvantages

• Not appropriate for early stage in rehabilitation or weak muscles.

• Could not accommodate painful arc in ROM.

• Expense of purchase and maintenance.

• Gradation in resistance depends on the manufacturers increments of weight.

Equipment for resistance training • Wide range of equipment for resistance training.

• Free weights • Elastic resistance.

Priniciples for selection of equipment Selection of the equipment should be based on the individual needs, abilities and goals, cost, space requirements, ease of use.

Principles for the use of equipment • Determine when to use, modify and stop.

• Determine if the equipment could be used independently.

• Stabilise body parts as appropriate. • Teach the appropriate exercise before adding resistance.

• Set up a regular maintenance, check up and replacement.

Free weights • Types Graduated weights that could be applied to the upper and lower extremities and trunk.

e.g. Dumbbells, weighted balls, weighted vests.

• Characteristics Provide constant load,

Advantages & Disadvantages

• Exercises could be done in different positions.

• Used for dynamic and isometric resistance exercise.

• Does not provide external stabilisation so the individual take time to learn the appropriate movement.

• Increase in the resistance depends on the graduated weights available.

Elastic resistance bands

• Elastic bands and elastic tubing.

• Color-coding denotes the level of resistance.

Properties of elastic resistance

• Effect of elongation of elastic material.

• Determination and quantification of resistance.

• Fatigue characteristics.

Application of elastic resistance • Selecting the appropriate grade of the material.

• Selecting the appropriate length.

• Securing bands or tubing.

• Setting up an exercise.

• Progressing exercise.

Reference

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Kisner C. and Colby L. (2007). Therapeutic exercise foundations and techniques. 5 th edition.