HackTwat
MuscleChemistry Registered Member
Muscle memory is what? We all know that if you lift weights and stop lifting for a few months (3-6 months), you will lose strength and muscle. However, if you start training back again, you gain the lost muscle or strength within a few weeks - as if the muscle remembers where you left off. This phenomenon is called ‘muscle memory’.
We used to believe this is largely due to the nervous system mechanisms. The nervous system mechanisms may explain the strength gains, but it doesn’t explain how you can gain back the muscle size so quickly.
But recent studies show that we may have finally solved the mystery of muscle memory
How did they solve it?
Unlike other cells, muscle cells have more than one nucleus (probably thousands). So why do muscles need so many nuclei? The nucleus is basically what controls the cell and since your muscles are a lot lot bigger and way more complex than other cells in the body, one or two nuclei just cannot do the job. So when your muscles get bigger, you have to add more muscle nucleus. The increase in nucleus with muscle growth has been shown in number of studies. It has been shown that people who take steroids and people who grow muscle easily have lot more muscle nuclei than normal.
Just like muscle growth, we believed that when we lose muscle, the opposite happens - we lose some nuclei since there is no reason for the extra nuclei to sit around. And this was supported in studies which showed as muscle shrinks in size, the number of nucleus decreases too.
Now here comes the surprise.
However, recently, studies using different animal models (denervation, unloading, synergic ablation) showed that as muscle atrophies or shrinks due to inactivity or detraining (until 3 months), there is no loss of muscle nuclei as we previously thought! As shown in the picture, the muscle size decreased by 50% (lines) but the muscle nuclie count (stained with green dye) remained the same.
So what? Since now the muscle has the same number of muscle nuclei after we stopped training, it is easy to build the muscle back to its previous size. So these muscle nuclei seems to acts like ‘memory cells’. They know how much muscle you had before you stooped training.
But why did we think muscle nuclei die with muscle loss?
The recent studies used a different technique to study these nuclei.
In previous studies they were counting nuclei which belonged to the connective tissue and other cells (satellite cells). And these nuclei do die with detraining. So researchers mistakenly assumed that the muscle nuclei die with muscle loss. But these weren’t actual muscle nuclei. The recent studies only counted the actual muscle nuclei and showed no loss .
Implications
We used to believe this is largely due to the nervous system mechanisms. The nervous system mechanisms may explain the strength gains, but it doesn’t explain how you can gain back the muscle size so quickly.
But recent studies show that we may have finally solved the mystery of muscle memory
How did they solve it?
Unlike other cells, muscle cells have more than one nucleus (probably thousands). So why do muscles need so many nuclei? The nucleus is basically what controls the cell and since your muscles are a lot lot bigger and way more complex than other cells in the body, one or two nuclei just cannot do the job. So when your muscles get bigger, you have to add more muscle nucleus. The increase in nucleus with muscle growth has been shown in number of studies. It has been shown that people who take steroids and people who grow muscle easily have lot more muscle nuclei than normal.
Just like muscle growth, we believed that when we lose muscle, the opposite happens - we lose some nuclei since there is no reason for the extra nuclei to sit around. And this was supported in studies which showed as muscle shrinks in size, the number of nucleus decreases too.
Now here comes the surprise.
However, recently, studies using different animal models (denervation, unloading, synergic ablation) showed that as muscle atrophies or shrinks due to inactivity or detraining (until 3 months), there is no loss of muscle nuclei as we previously thought! As shown in the picture, the muscle size decreased by 50% (lines) but the muscle nuclie count (stained with green dye) remained the same.
So what? Since now the muscle has the same number of muscle nuclei after we stopped training, it is easy to build the muscle back to its previous size. So these muscle nuclei seems to acts like ‘memory cells’. They know how much muscle you had before you stooped training.
But why did we think muscle nuclei die with muscle loss?
The recent studies used a different technique to study these nuclei.
In previous studies they were counting nuclei which belonged to the connective tissue and other cells (satellite cells). And these nuclei do die with detraining. So researchers mistakenly assumed that the muscle nuclei die with muscle loss. But these weren’t actual muscle nuclei. The recent studies only counted the actual muscle nuclei and showed no loss .
Implications
- Muscle memory phenomenon can be largely explained by muscles maintaining their muscle nuclei during muscle loss or detraining.
- These results are yet to be replicated in human studies.
