How to fight against muscle soreness and tendonitis?
It is common to have muscle soreness or tendonitis after sport. Nutrimuscle helps you to better understand your sensations and suggests solutions to fight against muscle soreness and tendonitis.
Soreness: deceptive sensations
Many counter-intuitive phenomena are generated during muscle soreness, which gives rise to numerous confusions and leads to erroneous conclusions.
A variable geometry perception
Muscle soreness is almost unnoticeable when the muscle is not under tension. It is only when you contract it or press on it that it appears. The stronger the contraction, the more intense the pain and vice versa.
Similarly, the intensity of soreness sensations fluctuates throughout the day. It is usually in the middle of the night that the pain is exacerbated. The same fluctuations in pain can be clearly seen in the case of a cold: it is in the evening, when you are trying to sleep, that the discomfort of a sore throat manifests itself most painfully.
Fluctuations in pain
Logically, for the same damage to the muscular tissues or the same irritation of the respiratory walls, the intensity of the pain should be constant throughout the day, but this is not the case. These well-known fluctuations reveal the dual nature of pain, particularly that caused by muscle soreness.
There are two causes for the feeling of muscle soreness:
- A local (or peripheral) element that directly affects the muscle(s) being trained.
- A central element in the brain, which modulates the perception of pain sensations from the muscles. Research shows that there is a nervous facilitation of pain sensation emanating from the brain (1).
This reduction of pain threshold does not occur when the muscles are relaxed. It appears when we put them under tension. Moreover, it is very specific, affecting only damaged muscles. It is at this central level that pain modulation will take effect.
Modulating the pain threshold
A very simple way to play with this second pain perception factor is to contract the injured muscle. At first it hurts a lot! Then, as the muscle warms up, the pain diminishes. It may even go away completely. Unfortunately, just because the muscle is warm doesn't mean that the soreness has really disappeared. It is just hidden, ready to reappear as soon as the muscle cools down sufficiently.
This is a typical example of a modulation of the pain threshold allowed by the brain because in certain dangerous situations we have to use our muscles. This is a survival mechanism. If we had had to run away from danger with muscles that were handicapped by the pain of soreness, we would have been much less successful.
An unexpected location
Unlike what one might think, the sensation of muscle soreness does not come from the contractile muscle fibers. The "soreness" is in fact mainly located on the fascia, the peripheral envelope of the muscles (2 - 3).
It is on this muscle sheath (fascia), much more than in the muscles themselves, that the most sensitive receptors to pain are located (4).
Researchers have determined this by injecting a pain-inducing substance in an extremely precise manner. In the days following an intense workout, the pain is increased tenfold when the substance is injected into the fascia, whereas it remains similar when the product is injected into the muscle itself.
A painful fascia is a sign of training damage. It must therefore be repaired for the soreness to disappear. This has nothing to do with the regeneration and growth of the muscle itself.
There is no doubt, however, that the muscle fibers have been damaged by training and need to be rebuilt and strengthened (5). However, it is not the contractile tissues that produce the bulk of the pain when you have muscle soreness.
What are the consequences?
There are several implications of these medical discoveries:
- You have to be very careful when the soreness is located at the junction of the muscle and the tendon rather than in the middle of the muscle, which means that your range of motion on the stretching part of the exercises has probably been a bit excessive. The risk of tendonitis or even tears is increased if you continue with this type of training.
- A muscle may appear to continue to be sore, but in reality has already recovered. It is just a sort of "echo" of the fascia pain, which tends to fade more slowly than the muscle damage itself.
- You should not hesitate to re-train on a muscle that has just passed its peak soreness. It is simply advisable to avoid forcing the fascia too much with large movements that will stretch it too much or with weights that are too heavy. On the other hand, exercises in longer series with a continuous tension, thus a lesser amplitude especially in the stretching phase, will be perfectly suitable.
Indeed, it is disturbing to note that it is local muscle growth factors such as NGF (Nerve Growth Factor) and COX-2 (cyclooxygenase-2) that also exacerbate the sensation of pain (6).
GDNF and the sensation of pain
We find the same logic of progression stimulation with an increase in the local production of growth factors for the nervous system such as GDNF (glial cell line-derived neurotrophic factor). Through a dual function, GDNF simultaneously exacerbates the feeling of local pain while allowing the reinforcement of the nervous signal from which our muscle power emanates (6).
So while re-training on soreness is painful, this strategy is also very effective in triggering the production of growth factors beneficial to strength and muscle growth.
- Massages on a foam roller or tennis ball can contribute to the regeneration of the fascia.
- Collagen hydrolysates (Peptan®) will be better at getting rid of "fascial" aches and pains than classic proteins (whey, casein, egg...). In fact, research shows that "classic" proteins are not the most appropriate for increasing muscle collagen regeneration, whether they are taken at rest or after strength training (7).
However, leucine has some ability to promote collagen synthesis (8). On the other hand, it has been shown that oral intake of collagen hydrolysates effectively stimulates the anabolism of collagen fibrils (9).
In this respect, Peptan® therefore has a dual role:
- Stimulate the anabolism of collagen in muscles, tendons and joints.
- Provide amino acids very specific to collagen, such as hydroxyproline, which are absent from classic proteins, BCAAs or the diet, even though their needs are increased by regular sports practice (10-11).
We now understand why studies that sought to reduce muscle soreness or make it disappear more quickly by increasing the intake of conventional protein have failed.
A historical turning point in the use of protein in sports
If muscle soreness is closely linked to damage to the collagen that makes up the fascia, this means that it makes sense to increase the intake of collagen hydrolysates in case of muscle soreness. This is because the fascia consists of connective tissue that is very rich in collagen.
The classic proteins, because of their composition in amino acids, target primarily the contractile tissues. They are much less effective in repairing damaged fascial collagen than collagen hydrolysates (which target collagen regeneration).
The primary role of Peptan®
This does not mean that collagen hydrolysates should replace these proteins, because Peptan® targets less the contractile elements of the muscles , hence the need to have a double source of proteins (classic + Peptan®).
This awareness of the primordial role of Peptan® in the athlete marks a turning point in our understanding of sports nutrition, highlighting the fact that the increase in collagen protein requirements is much greater than previously thought; the more intense the training, the more vital the need for collagen is for the athlete (10-11).
Can we be immune to muscle soreness?
After certain training sessions that were predicted to be very "sore", the masochistic tendency of the athlete leads him to be disappointed if he does not feel any muscle pain. But as we have seen above, the central aspect of pain due to muscle soreness allows the brain to play many tricks on us. It is important to check the veracity of these perceptions so as not to draw the wrong conclusions from the supposed absence of soreness. On the other hand, some people think that they never feel aches and pains. Is this really the case?
In order to check this effectively, there are two control techniques. They consist of using :
- Strong local pressure obtained with a massage on a tennis ball or a foam roller, exerting as much compression as possible.
- Electro-stimulation, which amplifies the nerve signal of the pain.
In theory, the ideal would be to repeat these tests in the middle of the night, at about 30-40 and 60 hours after the training session that is supposed to have caused soreness. This is obviously not practical. However, we recommend that you test yourself in the morning, on cold muscles, rather than in the evening.
Often these tests will reveal a sore muscle when it was thought to be undamaged. These tests allow us to check:
- The veracity of our sensations.
- The accuracy of the conclusions we draw from them.
- The speed of recovery after training.
Importance of Peptan® for tendon recovery
Following weight or physical training, a profound restructuring of the collagen fibers that make up the tendons is triggered (12).
Without a supply of collagen proteins, this restructuring will be delayed or incomplete, which can lead to injuries; slight temporary pains at first, which can then turn into tendonitis, which can no longer be removed (13).
Tendonitis: insufficient recovery
And this is without mentioning the constant regeneration of tendons, which is intensified by physical activity (10-11).
Thus, tendonitis is nothing more than insufficient recovery of the tendons due to training too closely together and/or a nutritional deficit that does not provide enough collagen protein precursors, whereas athletes have increased needs.
Hydrolysis: the key to Peptan®'s effectiveness
Collagen has historically been considered a poor quality source of protein, as its absorption is poor. However, thanks to the hydrolysis of amino acids, the absorption of Peptan® collagen hydrolysates reaches approximately 95% (14).
This enhancement by hydrolysis places Peptan® among the best proteins, not for feeding the muscle itself, but the whole sheathing architecture that surrounds it, such as the tendons, the fascia, the extracellular matrix...
For a perfect anabolic synergy, Peptan® can be combined with BCAAs.
Fighting against muscle soreness and tendonitis: conclusion
Collagen proteins should be used as soon as you start a sport activity, in the same way as "classic" proteins, because our needs are much more increased than we thought until now.
Do not wait until you are in pain before reinforcing your collagen supplementation.
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