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Zillagreybeard 3 years, 4 months ago.
CNS Fatigue and susceptibility to Muscle Damage
Discussion in 'Training' started by Zillagreybeard, Jun 25, 2021.You must be logged in to reply to this topic.
Baseball9Unblocked4 replied 3 weeks, 6 days ago
Sciroxx replied 1 month ago
steven johns726 replied 1 month ago
CNS Fatigue and susceptibility to Muscle Damage
Generally speaking, it’s completely normal to experience fatigue after a training set/training session, and in many cases, it dissipates quickly after a day or so.
However, if it lasts for several days, it’s likely being caused by muscle damage, as a result of excessive training volumes.
In a great article and review written by @chrisabeardsley he lays down the possibilities through which this mechanism can be explained. The specific cause is still unknown, however two are the main school of thoughts:
1) One hypothesis suggests it is purely mechanical: the disruption of the sarcomeres & cytoskeleton occur due to mechanical tension.
2) The other suggests there’s a strong biochemical element involved, through the release of proteases in response to an increased calcium ion influx in the sarcoplasm… and it’s likely the more plausible one.
Quite in fact, Calcium (Ca2+) is responsible for a whole lot of muscle-related processes: first of all, it allows muscle fiber contraction, and then, it’s also involved in muscle fiber degradation (when there’s too much of it).
This means that it’s very important for the muscle to control the levels of Ca2+ in the muscle & avoid overload, since that triggers the release of proteases (Calpains) that degrade parts of the muscle fibers.
Eccentric contractions are known to be more “muscle- damaging” than concentric ones, for example, and the cause has to do with to the fact that eccentrics seem to activate “SACs” (Stretch Activated Ion Channels) that allow more Ca2+ Influx concentration.
Which fibers get damaged the most ?
Type II fibers seem to undergo more damage than Type I.
In fact these fibers get very easily damaged, likely due to the fact that they contain fewer number of mitochondria, therefore when we’re performing long-lasting contractions, and high amounts of Ca2+ get released, Calpains get activated causing the breakdown of parts of the muscle cells…