Structural Changes to the Nervous System
Performance with age diminishes in all activities, albeit day to day movements such as putting the shopping away, to physical / sporting activities. Sadly this will happen to all of us (hopefully) and the risks of injury and falls increase dramatically as we get older. By looking after who we are now, in the present, we will be giving our future selves a head start in the battle against ageing as we grow older.
Below I hope to provide you with some facts to enable you to gain an understanding as to the physiological and anatomical changes to our Nervous System which occurs as we age.. and how best we fight back against the ageing process and reverse what changes we can!
The Nervous System
Briefly...The nervous system is the main control and communication centre of the body. It is responsible for the initiation and control of all human movement and multiple regulatory functions of the human body.
It consists of two main parts, namely the Central Nervous System (CNS) and Peripheral Nervous System (PNS).
The CNS is the control base for the whole nervous system and is comprised of the brain and spinal chord. All nerve impulses that stimulate muscles to contract and create movement of the body originates from the CNS.
The PNS consists of all branches of nerves that lie outside the spinal chord and controls voluntary (concious movement such as standing, walking) and involuntary movement (digestion etc).
Most changes occur in the brain, nervous cells / neurons and hormones that control activity of the nervous system.
With age comes a decrease in brain volume. This results in a loss of neurons and neurotransmitters which are the primary communication structures which allows signals / messages to and from the brain to the Central and Peripheral systems to travel slower.
Age related changes are sensory and behavioural. For example, a decline in vision, hearing and proprioception. This may result in a decrease to visual acuity, poor hearing and difficulty listening to instructions and issues relating to balance and mobility.
Furthermore, there are behavioural changes which relate to response speed, the ability to process information, memory loss and the ability to learn new motor skills.
These result in the following fitness potential considerations:-
Reduced muscular strength
Reduced muscle power
Reduced movement speed
Reduced muscular endurance
Reduced flexibility and range of motion
Reduced balance and coordination
Reduced postural stability
Reduced short-term memory
The good news is that physical activity and aerobic fitness can have a significant positive effect on the structural health of the nervous system.
Those adults with a higher aerobic fitness level show an increase in brain volume and behavioural changes such as response speed and cognitive fitness.
Short duration exercise is as effective as moderate duration although the greater benefit to behavioural speed is longer duration programmes focusing on aerobic and strength training.
Furthermore the health benefits are aerobic exercise significantly reduces the risks of hypertension (high blood pressure) and hyperlipidaemia (high cholesterol) as well as dementia prevention and slows the progression of alzheimer's disease.
As we age the total number of motor neurons decline and through routine physical activity it is known to slow and even reverse the structural deficits responsible for functional capacity.
In conclusion, exercise programmes focusing on stabilisation, strength and power training might facilitate the needs of the adult population by emphasising the ability to balance and navigate in later life.