When muscles contract/tense up, they become shorter. If you stretch (relax) your muscles, they lengthen. Stretching is therefore also used to relax the muscles. We use this as a basic principle in the exercises we give to our clients.
It is important for the function of the muscles that a state of tension, muscle tone, is also present when at rest. In the case when tension is too low, we call this hypotonia. In the case when tension is too much, we call this hypertonia.
Strenuous physical activity usually leads to acidification of the muscles. During strenuous physical activity or sport, the muscles need more fuel (carbohydrates that are converted into glucose/sugar) than they normally do. Burning fuels produces waste.
This is the lactic acid that is formed. Yet lactic acid itself does not cause acidification. Lactic acid breaks down into lactate (which in turn supplies energy to the muscles) and H +- ions. These H+-ions are responsible for acidification.
Acidified muscles are painful and quickly become tired. A loss of strength occurs. This is caused by the fact that the muscle tissues are no longer able to sufficiently pull (contract) together. The muscles feel inflamed and often that person is no longer able to perform any strenuous activity.
Incidentally, muscle pain on the following day is not caused by acidification, but by small tears in the muscles. This pain only occurs later, between 24-48 hours on average after this strenuous activity. This is a clear distinction from acidified muscles: the pain occurs almost immediately here.
Moreover, muscle cramps are not caused by lactic acid, instead by Ca-ions. Nevertheless, it can also occur at the same time as acidification.
Acidification can be prevented by building up a good level of fitness for improved oxygen intake and by training muscles properly.
Trained muscles acidify less quickly than untrained muscles. A good warming-up is also very important. Recovery time for acidified muscles is relatively quick: by resting and catching one's breath the balance in the muscles is soon regained. Keep on moving muscles: due to the pumping movement of the muscles, waste products are more easily removed.
If waste products are not adequately removed, (painful) hardening of the muscles can occur. And by this we do not necessarily mean the trigger points (a trigger point is mainly caused by an overactive nervous system). We can alleviate this hardening of the muscles by improving circulation and we can do this by giving a therapeutic massage or sports massage, amongst other things.
A muscle needs to rest after a considerable amount of overexertion. It is therefore recommended not to massage immediately after a considerable amount of overexertion. Massaging later on is better for recovery. There are hardly any contraindications when it comes to massaging muscles, but be aware of topical inflammations and specific illnesses (!!) Please note: the general contraindications for massage also apply here !!).
When muscles contract/tense up, they become shorter.