Building muscle from within: The Gut-Muscle Axis

Building muscle from within: The Gut-Muscle Axis

Some wacky scientists in Sweden have been pulling sleeping bears out of their dens, to work out how they can sleep all day and still maintain strong muscles throughout their hibernation.

They have now found that the gut, among many other things, is also responsible for keeping up muscle mass in animals that hibernate. Brown and black bears, squirrels, and even female polar bears hibernate with their young cubs, in case you were questioning the hibernation picture above! Then they wake up and take off like their muscles never had a break at all.

So why can animals that hibernate sleep all day and not wither away?

This has been puzzling scientists for decades who have been looking at animal metabolism and genetic switches as the key to this. One process is that the body metabolism slows down – so all cellular processes, ageing and waste production are reduced, which is helpful.

But this cannot be enough. You can imagine that, just like an astronaut in space, if we sat down and didn’t use our muscles, they would start to wither away. If we have been in hospital or bed-ridden for a longer period, our muscle mass suffers.

Now, science has found a BIG change that happens in these animals, and it happens in the gut. They go into a fasting state for months, which means that they are also starving their microbes who will also have to hibernate; except for a few microbes with a very important job to do.

Nitrogen recovery bacteria

There are specific bacteria in the gut of hibernating animals that can recirculate the nitrogen from urea in the blood stream, back into small proteins that then become the regenerated building blocks for muscle tissue again. Effectively the gut microbiome shifts to become a regenerating, life-support machine. When the hibernating squirrels or bears wake up, they are ready to go with minimal wastage of muscle.

Lucky for the bear that he wakes up in strong shape – but maybe not so for an unwitting person wandering the forest in spring!

Other animals too, even ones that don’t hibernate, have evolved gut microbiome-to-muscle processes, that capture urea and build a lot of muscle – think about Ferdinand the bull who just sat under the trees smelling the flowers, but had a body that made him look fierce, on a diet of just grass!

Human gut flora can recycle some nitrogen too

The human body can also regulate nitrogen processes in the gut, to deliver more micro-proteins when needed, and fewer when we don’t have protein deficiencies. We now know that we secrete urea in our saliva and gut mucous throughout our digestive tract. Even breast milk has urea and promotes beneficial bacteria such as the probiotic fermenters Lactobacillus and Bifidobacteria. These bacteria can regenerate urea to lysine that we then build into proteins, which keeps us in good muscle balance.

But we need to keep up a nitrogen rich diet too

Humans still need to ingest nitrogen, however, to keep up their muscle mass, as we cannot yet sleep all day and stay strong. We have to eat well, sleep well and exercise regularly, although short bouts of fasting could be beneficial to trigger gut agility.

Nitrogen-rich seaweed for microbes

Eating well is easier if we just add a bit of seaweed to our daily routines, and PhycoHealth seaweed products are tailored to keep up a high nitrogen profile with all essential amino acids, which your gut bacteria can digest to create the proteins you will need.

Nitrogen rich seaweed

These bacteria, like Lactobacillus and Bifidobacteria, also need good prebiotic fibre of which seaweed is a good source. Both of these bacteria increased in studies we have undertaken on human gut health using our SeaFibre extract, which we use in our SeaFibre range. Additionally, the anti-oxidant properties of seaweed have been shown to reduce oxidative stress and protect the muscle building process during exercise.

A bear listens to its body which has evolved to the right food, the right sleep regime and plenty of exercise in the summer. Trust in that your body and gut knows what it needs too, and that it is agile and can adapt with you if you listen to it. 

Our gut microbiome goes with us where we take it - so we had better guide it right.