Originally posted by edd
I don’t have such a science theory grip on this stuff as 2Lap has. But I thought I’d put a laymen’s spin on this.
When you train and condition your body, aerobically, anaerobically. The whole body ( yes even the brain ) adapts to the new demands. I don’t know of anyway of isolating and training the central nervous system from an endurance perspective. Though I believe the CIA does, seriously, no joke.
Sports Science ( as far as I know ) doesn’t get too focused on emotions, mainly interested in “aggression” “ fired up and focused” I think the term is..
The connection between the emotions and fatigue in the central nervous system is very real and I believe, relatively unexplored.
I’m hanging on the edge of my chair waiting to see what this question produces!
This is almost as big a can of worms as the physiology side of things and I agree with you edd... its not very well explored.
Here are some basics (as I'm not a psychologist someone might want to help me out)....
When we talk about neuromuscular factors we are generaly talking about the way the brain uses neurones (nerve cells) to control muscles. Basicaly the brain (or more correctly the central nervous system) contols the way that muscles are used, to get a muscle to contract it 'recruits' motor units (or bundles of muscle fibres controled by a single motor neurone) and tells them to contract. This is done by sending electrical impulses via the neurones from the CNS to the muscle. The brain can produce a more forceful contraction by 'recruiting' more motor units or by sending more impulses in a space of time.
Training the neural system does 3 things...
1. Increases recruitment - untrained people don't recruit all of their motor units in a muscular contraction, training increases the number of motor units recruited. Effectively with training you can use 'more' of your muscle!
2. Increases impulses - as all impulses sent by the brain are of the same intensity/strength; the strength of the impulse cannot be used to change the force of the muscle contractions. By training, the brain is able to send more impulses in a given period of time (i.e. at a greater frequency). Kind of like changing your cable modem for broadband.
3. Skill - Its all very well recruiting motor units and at a high frequency, but if this is not a coordinated action then whats the point? For example, you can't do any external work if you coordinate the tricepts and bicepts at the same time!! With more training the accuracy of the contraction of individual motor units and individual muscle improves. This is important for efficiency and for reducing coordination errors. This training effect is easily seen in a young child learning to work.
As edd points out emotions can be used to 'optimise' these factors. Agression or motivation, perhaps through adrenaline and other hormonal changes, will increase the stimulation of the central nervous system. Calm or relaxation, will reduce stimulation. This is easily seen as changes in HR without changes in physical activity. However the wrong emotion or level of stimulation at the wrong time can be disastorous (look for 'inverted U hypothesis' or 'catastrophy theory' on google).
Fatigue of the CNS or in the neurones (or between neurones) can result in lower stimulation of the muscles or less accurate stimulation. Good examples are when you are tired; seen as lower strength and jerky or drunken movements.
How do you train this? Well avoiding specific psychological interventions (like imagary); specific on the bike training will allow your neuromuscular side to adapt as required. Only pedaling allows you to develop pedaling and cornering at speed alows you to develop coordination while balancing at speed. Its also best to train these factors in a fresh and fatigued state.
Looking at strength as an example... much strength occurs as imporvements in muscle contraction via improved neuralmuscular control (most of the strength gains that occur in a program during the first 4 weeks are dur to this). These improvements are very specific and as a result don't transfer to cycling in a useful way. Neural adapations are often the fastest to develope and lose; yet can take many many years to perfect!!!!
How do you measure this in a lab? Using EMG the pattern and amount of electrical activity in any muscle can be meausred. This is quite a simple thing to do, simply sticking electrodes over a muscle and contracting the muscle produces an EMG signal. Although this has little practical use for the average cyclist (and is very expensive to do).