Everyone is probably familiar with this feeling: sore muscles. But does the pain after intensive training really only come from overworked muscles? Research has come up with a new approach: it assumes that fascia soreness also exists.
The aching feeling after a heavy workout means that the affected areas of the muscles can no longer perform their "normal" function, which is particularly evident during eccentric movements such as running down stairs. Research assumes that fascia soreness also exists.
Many theories on muscle soreness
As already mentioned, the understanding of muscle soreness has changed again and again over time. One of the first (and now obsolete) theories was the lactate theory. Muscle soreness is said to occur precisely when a lot of lactate (lactic acid) has accumulated in the muscle. However, the problems in the trained muscles normally only occur one to two days after training and lactate has a half-life of just 20 minutes in the muscle, which makes this theory very unlikely.
In addition, strength training often does not build up as much lactate as, for example, a middle-distance runner, where concentrations of 20 mmol /l can be measured. Another theory links the development of muscle soreness to free radicals that are supposed to be released during training. But even when attempts were made in laboratory tests to reduce the radical level in the muscle, the pain symptoms did not disappear.
The general theory in sports science on the development of muscle soreness is based on micro-tears in the muscles. These are caused by stimuli to which the muscles are exposed during hard training. The tears are found in the smallest components of our muscles, the so-called sarcomeres. These consist of actin, myosin and titin filaments and are separated from each other by so-called Z-discs. If you look at tissue affected by sore muscles under an electron microscope, you can detect tears in the Z-discs. This finding solved the mystery of the "hangover" after training for the time being.
Experiment on fascia soreness
The intensification of fascia research in recent years has not only led to new insights into human connective tissue, but also for training. This also applies to sore muscles. Even better microscopy techniques show that the Z-discs are torn when muscles are sore, but they also show that the fascial tissue around the muscle is significantly more stressed. As many pain receptors are also located in the fascial tissue, it seems obvious that sore muscles become sore fascia. This finding was to be proven by an experiment that looked like this: By repeatedly stepping up and down on a box, sore muscles were induced in a group of test subjects. To enable the researchers to identify where the pain actually originated, they injected the test subjects with saline solution. One group was injected into the muscle and the other into the fascia. Both groups had muscle pain. Only one had more pain than the other. Which one do you think it was? Exactly, the one that had a saline solution injected into the fascia.
Training the fascia correctly can prevent pain later on. 
Of course, this alone is not definitive proof. But it does show that the fascial system should be taken seriously as a source of muscle soreness, or rather fascial soreness. Because so far it only seems clear that the fascia is somehow affected, but not in what form. Be it small tears, inflammation or a stronger perception of pain. However, fascia soreness will definitely need to be investigated further.
And after training?
A few days after exercise, the pain disappears again and the body protects itself from fascia soreness by adapting. As we have probably all noticed at some point, the hangover is delayed. This is due to the tears in the muscles/fascia through which water penetrates the tissue. This flushes out inflammatory substances that hit pain receptors and cause pain. This happens around twelve to 24 hours after exercise.
Conclusion on fascia soreness
It is still not definitively clear what muscle soreness is and how it occurs. Fascia research has provided a new approach that is entirely plausible and conceivable. Nevertheless, fascia soreness will continue to be researched so that it can be understood and taken seriously. What is actually correct now will have a major impact on the treatment of muscle soreness. For fear of increasing muscle tears and prolonging muscle soreness, the micro-tear theory advises against massage and recommends light exercise and, above all, waiting. However, if it really is a case of sore fascia, then fascia mobilization and foam rolling are the methods of choice. One thing is still clear: it will be a while before we really know what causes sore muscles.
Source: IST
Published on: 10 September 2015