What is Posture?
Essentially, it is the relative arrangement of the segments of your body, with minimal work being done by the muscles and bones to hold a position.
Good posture is protective against injury and helps set you up for movement and support of organs and other tissues. Whilst having ideal alignment of your spine and body wont guarantee you wont experience injury or pain; it is the ideal for which efficient movement is based.
Bad (poor) posture increases your risk of muscular imbalances developing. Imbalances can place undue strain and force through your muscles through your passive structures. These include ligaments, tendons, and joints.
A poor postural position can also result in your center of gravity (COG) not being balanced over your base of support. This sets you up for altered movement patterns and an increased risk of injury.
Whether your an athlete or your training for improved health and fitness; maintaining an optimal COG during movement will assist you to increase strength and performance.
First a word about muscles, their structure and how they do their job.
Understanding Muscles with Posture
Your muscles are made up of two different types of muscle fibres: slow twitch and fast twitch.
Fast twitch fibres are largely in phasic muscles, which are designed to turn on, move the joint, and turn off. They use glucose to do their job, and fatigue relatively quickly. The muscles in your arms and hands are a great example fats twitch fibre. The muscles in your arms and hands are designed to move your elbow, shoulder and the joints within your fingers and wrist. They can move the joints quickly and can exert a high level of force to undertake movement.
Slow twitch muscle fibres are the alternate to fast twitch fibres. Slow twitch muscle fibres use oxygen (aerobic) as fuel to do their job and take a long time to fatigue.
Slow twitch muscle fibres are largely in postural muscles, they need to be active whenever you are in a standing position as they hold your body position against the compressive forces of gravity. Slow twitch fibres can activate over large periods of time and are designed to exert minimal force and energy.
There are some muscles which have both fast and slow twitch fibres. A great example of this is your gluteal muscles which are designed to move your hip joint with large forces in running and jumping, but they also need to act against gravity in standing. As such they play a role in both force production and
The other important aspect to muscles in relation to understanding posture is to know that whenever a joint moved by your muscles; there is always one group of muscles which are shortening (concentric contraction) and another group which are lengthening (eccentric contraction)
So, what does this mean for Posture?
Function of Good Posture
Body positions that you hold or activities you undertake over long periods of time begin to shape your posture through repetition. Repetition of movement or position is something that we repeat consistently over extended periods of time. This begins to train your nervous system so you unconsciously hold this same body position or movement; continually and automatically.
In the case of learning a new skill such as a golf swing; repeated and consistent repetition of the correct movement pattern positively trains your nervous system to enable you to get better at the skill.
In the case of sitting at your desk and computer for long periods (day after day); you teach your nervous system to hold incorrect postural alignment which can increase your risk of injury and pain.
With long periods of sitting at a computer, the muscles in the front of your neck become chronically shortened, whilst the muscles in the back of your neck are chronically lengthened. This constant biomechanical position results in changes to the position of the joints in your neck and over time a changed postural alignment.
The change in the postural alignment of your neck with prolonged sitting at a computer occurs because of the repetition of this misalignment and the resulting training of your nervous system to hold this faulty position.
Changes also occur in the way muscles recruit themselves to undertake a movement, and sometimes delay how and when they activate. This puts a greater stress on the body’s passive structures and on other muscles that don’t have the size or physiological characteristics to produce large amounts of force.
A really good example is sedentary behaviour; this changes the balance of your pelvis, how your abdominals, back extensors, gluteals and hamstrings, and hip flexors hold it in a neutral position. When you’ve been sitting for long periods, your abdominals, gluteals, and hamstrings become weak and lengthened; and your back extensors, and hip flexors become chronically shortened. This pulls your pelvis into an anterior tilt, and rotates it forward. One of the side effects of the gluteals becoming lengthened and having a delayed activation, means that other small muscles try and do the job of these big muscles, and they don’t have the size or metabolism to do the work the gluteals do.
This is particularly common in the case of a delay in activation or weakness in gluteus Medius. This muscle is important in walking and when it is weak (or has a delayed activation) a small muscle in the front of the hip starts to take over (tensor fasciae latae). This small muscle tries to do gluteus Medius job, and because it is not designed to do so it will fatigue very quickly causing pain.
The Exercise Physiologists at Inspire Fitness for Wellbeing assess you individual posture and biomechanical needs when designing an exercise program.
Prior to commencement of an exercise program, Inspire Fitness Exercise Physiologists determine what movements need improving, and what muscles need strengthening or stretching, to improve your posture and reduce your risk of injury!
Our postural analysis and observations through our detailed screening process is designed to ensure your exercise program is designed for the unique needs of your body!
Source: YouTube Observation and Posture Analysis