Section Three: Physiology

Section Three:

Physiology

To understand how to plan and teach a safe and effective Supple Strength class, we need to revise the basic muscle groups and muscle actions.

Task 1

Complete the following table:

Muscle Group Attachments Joint(s) Crossed Main Function

Rectus Abdominis

External Obliques

Internal Obliques

Transversus Abdominis

Quadratus Lumborum

Erector Spinae

Multifidus

Pelvic Floor

Abdominal Balloon

At the front of the trunk are the 4 major abdominal muscles, at the back the erector spinae and multifidus and at the bottom is the pelvic floor.

With the inclusion of the diaphragm the above muscle groups (excluding the erector spinae) make up the abdominal balloon.

When breathing is controlled the abdominal balloon creates a supportive cylinder that protects the spine.

The Core Muscle Groups

Rectus Abdominis: runs from the lower ribs to the pubic bone. They work to flex the trunk and lift the tail when lying on the back.

Internal and External Oblique: runs diagonally at the side of the abdomen (they work to twist and rotate the spine). It starts at the pelvis and goes to the ribs in a diagonal line. The Internal Obliques help stabilize the spine; the External Obliques are more responsible for movement.

The Tranversus Abdominis (TVA) – attaches from the pelvis and tissue that covers the spinal extensors and travels horizontally. It runs into the sheath that covers the Rectus Abdominis and works to pull the abdomen in and is a major support for the spine.

The Quadratus Lumborum – is positioned between the ribcage and the pelvis at the side and back of the trunk. The Quadratus Lumborum stabilises the spine when a force tries to bend the spine sideways. It engages when you carry an object in one hand, for example, a shopping bag.

The Pelvic Floor – is attached to the inside of the pelvis and runs from the coccyx or tailbone to the pubic bone and has a counter relationship with the abdominal area.

Multifidus – attaches to the transverus and spinous processes. It is responsible for extending the vertebrae. It will bring about movement up the length of the spine. Each section will only cross over two of three vertebrae, which means it can extend individual sections.

Erector Spinae – attaches to the Sacrum, Ilium and Thorax to the Occipital Bone (base of the skull). It is responsible for extending the spine and rotating the thoracic area.

It is important to note that the Gluteals, and Latissimus Dorsi attach to the TFL (Thoracolumbar Facia). They help to maintain tension in around the spine and resist flexing forces. This can help protect the spine when flexing in a standing or sitting position.

All of the muscle groups above have an obvious function, however, the majority of movements require all of the abdominal group and back muscles to work in harmony, they will all be activated and work together.

Muscle Actions

The co-ordination of the various muscles responsible for movement has been categorised into 4 primary functions:

Prime Mover/Agonist: When a muscle contracts to create movement, it is solely acting as a prime mover.

Antagonist: The muscle opposing the prime mover. This muscle relaxes whilst the agonist contracts.

Fixator: are muscles that stabilise parts of the body to prevent unwanted actions. The fixator contracts to support the bone onto which the prime mover is attached.

Synergists: assist the prime mover

Student Notes:

Types of Muscle Contractions

Muscle contractions can be broadly labelled ISOMETRIC or ISOTONIC.

Task 2

Give a definition of each type of contraction:

Isometric

Isotonic

Concentric

Eccentric

Muscular Strength and Endurance

Both muscular strength and endurance will probably be utilised in a Supple Strength class depending on the fitness level of the individual. It is important to remember that what is endurance for one person may be strength for another. Because the exercises are performed very slowly most individuals will experience some strength as well as endurance gains from the session.

Muscular Strength can be defined as:

The maximum amount of force that can be generated by a group of muscles, against a resistance in one contraction.

A general rule is HIGH RESISTANCE and LOW REPETITIONS of 6-10 reps.

Muscular Endurance can be defined as:

The ability of a muscle to exert sub-maximal force against a resistance over an extended period of time.

A general rule is LOW/MODERATE RESISTANCE and HIGH REPETITIONS of 15-25 reps.

It is useful to think about strength and endurance, as a continuum, with strength at one end and endurance at the other. For some exercises in a Supple Strength class, participants will be working for strength and some exercises will be endurance. This will depend upon the individual’s fitness levels and the design of the class. For example, when putting press-ups in the ‘salute to the sun’ sequence, they can be slowed right down and a more advanced position can be chosen to make the sequence challenging and more strength-based for the fitter exercise.