Introduction to Therapeutic Exercise

Original Editor - Jess Bell based on the course by Richard Jackson
Top Contributors - Jess Bell, Wanda van Niekerk and Kim Jackson

Introduction

When considering exercise prescription in physiotherapy practice, it is important to understand the difference between therapeutic exercise and general exercise. General exercise is essentially a “work out”. It is exercise for wellness, overall health, appearance, fun, leisure etc.

Therapeutic exercise is specifically for individuals who have a physical problem / impairment, which is often painful.

“Therapeutic exercise is distinguishable from other forms of recreation because it is a purposeful, body-building activity, often prescribed by experts [...], drawing on their knowledge of bodily function to engage in a powerful form of anatomo-politics”.

Rehabilitation professionals must be able to assess, analyse, and determine the cause of a client’s pain or impairment. Exercises are then prescribed in order to address deficits in:

• Mobility / flexibility
• Strength and power
• Neuromuscular control
• Muscular endurance

Why Include Therapeutic Exercise in a Treatment Plan?

Exercise interventions are beneficial as they enable individuals to self-manage their symptoms. Moreover, there is a large body of research to support its use in clinical practice.

• Research supports the use of exercise interventions for long-term changes when compared to manual therapy alone
  • A systematic review by Lin et al. appraised 44 clinical practice guidelines for musculoskeletal pain conditions. They found that exercise was recommended in all guidelines. However, when manual therapy is utilised, it should be used alongside other interventions (i.e. exercise, psychological therapy, information / education, activity advice).

• Exercise is supported over other therapeutic interventions

Terminology

Table 1 provides a list of terms that are often used when discussing therapeutic exercise.

Table 1. Therapeutic exercise terminology

Term	Definition
Exercise	Rotating joints in specific ways to challenge muscles
Form	A "topography of movement" or a specific manner of performing an exercise to maximise safety and ensure gains in muscle strength
Repetition / rep	A cycle consisting of controlled lifting and lowering of a weight
Set	Several repetitions performed in a row without a break
1 repetition maximum / 1RM	The maximum weight that an individual can lift once
Agonist	Prime mover
Antagonist	Opposite of an agonist, can control rapid movement eccentrically
Synergist	Muscle(s) that stabilise(s) a joint around which movement occurs
Tempo	The speed at which an exercise is completed; tempo affects both the amount of weight that can be moved and the muscle

Tissue Damage, Pathogenesis, Pain and Performance

Injury and tissue damage cause a disruption in joint biomechanics:

• Pain from an injury or surgery results in a cascade of changes that can cause disruptions to the joint and, potentially, ongoing pain. This pain may last for years. This, in turn, can lead to degenerative changes such as facet arthritis, accelerated annular degeneration, and nerve root irritation.
• Tissue damage occurs when excessive stress / strain is applied to a tissue (i.e. the force exceeds the strength of the tissue). Injury may occur after a single insult or from repeated loads. Tissue damage leads to motor control problems and, subsequently, long-term pain and degenerative changes.

Injuries can also cause motor changes. Research has shown that individuals who report significant low back pain experience changes in their motor control systems.

Therefore, the challenge is to train the stabilising system during steady-state activities and during rapid voluntary motions, so that the body can withstand sudden, surprise loads. However, the presence of pain prevents the re-establishment of “healthy” motor patterns. And just as motor patterns are affected by injury, inappropriate motor patterns can also cause injury. Therefore, perturbed motor control systems are both a cause and a consequence of injury.

However, as discussed above, there is considerable evidence to support the use of therapeutic exercise as an intervention for musculoskeletal injury or pain. It can improve:

• Range of motion, flexibility and mobility
• Muscle activation
• Neuromuscular coordination
• Joint stability
• Strength and power
• Muscle endurance

Progression and Regression Design Principles

When prescribing exercises, it is important to understand how to progress and regress exercises. If patients are improving, exercises can be progressed. However, if they experience an increase in pain / symptoms, it may be necessary to alter certain parameters, including:

• Sets
• Repetitions
• Speed
• Resistance

Phases of Exercise

• Activation
  • Firstly, it is necessary to determine if the patient can activate the affected muscle - i.e. is there a connection between muscle and brain?
• Tissue healing
  • The phase of healing will have a significant impact on which exercises are given
• Stabilisation
  • Joints are stabilised by the muscles
• Mobility
  • As stability increases, range can be added
• Muscle performance improvement
• Advanced coordination and skill
  • Progressively add difficulty in movement patterns to restore normal functional abilities

Teaching Methods for Exercise

• Verbal cues
• Mental imagery
• Visual feedback
• Manual cues

Various cues used to assist motor learning are discussed in more detail here.

Types of Muscle Contraction

Figure 1. Types of muscle contractions.

The types of muscle contraction are:

• Isotonic
  • Concentric (shortening)
  • Eccentric (lengthening)
• Isometric
  • Static / holding
• Isokinetic

Eccentric exercise:

• Negative force of a muscle contraction (i.e. negative work)
• Leads to muscle hypertrophy
• Beneficial for tendons
• Causes delayed onset muscle soreness
• Should take no less than 4 seconds

Isometric exercise:

• Muscle contraction without any movement / change in muscle length

Concentric exercise:

• Positive force of a muscle contraction (i.e. positive work)
• Used to build endurance and increase tolerance to exercise
• Should take no longer than 3 seconds

Concentric versus eccentric:

• Eccentric strength must be greater than concentric strength
• The eccentric load must be greater than what an individual can lift concentrically

The following video provides a detailed discussion of concentric, eccentric and isometric muscle contractions.

Overload Principle

In order to improve strength, increased load must be applied to a muscle. This will increase the muscle's capability. Progressively adding stress to the system means that it can adapt. It also prepares the body to do more in the future.

The following video provides a brief discussion of the overload principle.

Learn more about some of the basic principles (such as specificity, overload, reversibility and individuality) in exercise physiology here.

Preparing the Patient

In order to prepare the patient for therapeutic exercise, please consider the following:

• Educate for success:
  • Discuss how to progress
  • Encourage patients to keep going once they have finished therapy
• Set expectations:
  • What is normal muscle soreness?
    • 24-48 hours
  • How often should exercises be performed?
  • How long will it take to make changes? It is important to note that:
    • It takes 4-6 weeks to achieve physiological changes in a muscle
    • Early increases in force production are associated with neural adaptations
    • A patient may ‘feel’ stronger before 4-6 weeks have passed

Programme Design

Table 2 provides a summary of the traffic light system. This system can be used to determine at what level an individual should exercise.

Table 2. Traffic light system for therapeutic exercise

Red light	Movement hurts and may cause further injury Pain before resistance “Hands-off” approach or isometric exercises
Yellow light	Movement does not hurt unless overpressure is applied Pain at resistance Treat with minimum to moderate manual techniques, exercise before pain
Green light	Pain after resistance Decreased chance to cause further injury Treat directly

General Principles

It is essential to target an exercise intervention and focus on the impairment (i.e. weakness versus sensorimotor or neuromotor deficit). Consider:

• Irritability and current level of function
• Reps and sets scheme
• Targeted impairment category
• Progressions (necessary to see changes)

Neuromuscular Education

Sensorimotor control is defined as "afferent and efferent information streams, as well as the central processing of these two, contributing to joint stability."

Sensorimotor impairment is associated with various musculoskeletal conditions, including neck pain, hand disorders, back pain, etc. Mechanisms for sensorimotor deficiency include:

• Impairments in the integration and processing of information in various parts of the sensorimotor system (e.g. sensory input, central nervous system, motor output)
• Neural inhibition is associated with pain, swelling, inflammation, joint laxity, and damage to the afferents of joints
• In knee pain, sensorimotor deficiencies have also been found in the non-injured leg:
  • This may be due to physical inactivity post-injury, reduced function, and impaired sensory feedback from the injured joint

For a detailed discussion of the sensorimotor system, please see this article, and figure 1 in particular: The sensorimotor system, part I: the physiologic basis of functional joint stability

The video below summarises the sensorimotor system.

Neuromuscular Training

Neuromuscular training programmes have been found to be effective in improving function and reducing symptoms for various injuries. To improve sensorimotor control, closed kinetic chain exercises are often performed in a range of positions.

Please note that closed kinetic chain exercises are exercises or movements where the distal body segment is fixed to a stationary object. Open kinetic chain exercises are when the distal body segment (e.g. foot) is free / not fixed to an object.

Progress function through motor learning principles:

• Consider the type of practice (components, variety)
• Closed to open kinetic chain; simple to complex

Progress function through movement:

• Frequency, intensity, duration (time)
• Endurance
• Single- to multi-joint; closed to open

The following video provides a basic summary of the FITT principles (i.e. frequency, intensity, time, type).

The process is as follows:

• Activation
• Re-education
• Motor learning
• Functional movement training

Remember that:

• The core musculature is key to the movement of the extremities
  • The extremities are tied to the spine
  • The spine must be stable

Strength and Conditioning

Strength is defined as the amount of force that a specific muscle or muscle group can generate.

Conditioning (endurance) is defined as the ability to “perform repetitive muscular contraction against some resistance for an extended period”.

"Strength does not equal stability".

Strength and endurance training have many benefits:

• Increased tissue vascularisation
• Increased structural integrity of connective tissue
• Improved lean muscle mass
• Increased metabolic rate
• Decreased body fat

Tolerance:

• Every individual has a tolerance for work
• Tissues are damaged if their load tolerance is exceeded
• Tolerance is lower in tissues that are already weakened by injury
• Understanding each individual’s tolerance will assist in choosing the appropriate dosage / load for each stage of training

Capacity:

• Every individual has a capacity for work
• Capacity is defined as “the sum total of all activities over a period of time” (i.e. the maximum physical exertion that an individual can sustain)
• People use up a portion of their daily capacity with every task they perform, including warm-up activities, poor posture (sitting or standing)
• Ideal training occurs when capacity and tolerance are increased together

Read more on: Neuromuscular Adaptations to Exercise

Principles of Conditioning

• Warm up / cool down
• Motivation
• Overload (see below)
• Consistency
• Progression
• Intensity
• Specificity
• Individuality
• Minimise stress

SAID Principle

The Specific Adaptation to Imposed Demands (SAID) principle is a framework on which strength and conditioning programmes can be designed.

• All training is specific to a particular task
• Specific skills or training may not be easily generalised or transferred to distinct activities

The following video includes a discussion of the SAID principle and other principles of exercise training.

Principles of Progression

Progressive overload:

• Increase or decrease difficulty with:
  • Reps
  • Sets
  • Speed
  • Complexity of exercise
  • Balance
  • Closed versus open chain
    • Best results come from including both open and closed chain exercises
    • Open to closed, closed to functional

Exercises can also be progressed by challenging the balance system:

• Unstable surfaces
• Head-turning
• Eyes closed
• Visual distraction

More information on balance training is available here.