Improve endurance stop muscle wasting. Why it’s a good idea to sauna?



We mentioned in a previous blog how beneficial heat stress has been shown to be in human and animal studies. In this blog we look at a few of the mechanisms for this.

These mechanisms can be a bit technical to explain but they point towards 3 main potential fitness benefits of heat stress/sauna.

  1. improved endurance

  2. reduced muscle loss after disuse

  3. improved muscle growth after disuse



How does the sauna cause these benefits?


Increase Heat shock proteins

Heat shock proteins play a huge role in this. As we age we make less heat shock proteins. But what are they and why is this important?

Our DNA makes a substance called RNA which transfers into proteins. Proteins control most of the functions that happen in our body. Heat shock proteins (HSP) function is to make sure that proteins in muscle cells (that do all the work in a cell) function properly. To do this they need to keep their 3D structure and HSP can help do this. Also once you have used a protein to perform a function HSP helps stop aggregation of these proteins (build up of used proteins) causing plaques related to neurodegenerative process like dementia. HSP protect against damage by making sure the protein structure is maintained.


Increase release of FOXO3

FOXO3 is a gene that activates lots of other genes that are responsible for stress resistance. Repairing damage to DNA in mitochondria and nucleus before cell stress causes mutations Which can lead to disease.

Also FOXO3 activates antioxidant genes to scavenge and detoxify some of the damage that has already started.

FOXO3 also activates a pathway to clear away damaged cells - autophagy. If this doesn’t happen when the cell dies it doesn’t function and just produces pro inflammatory molecules that damage other cells And can lead to disease.

FOXO3 activates genes that are involved in immune function and also stem cell function which is important for replenishing damage cells and therefore lead to organ dysfunction.


Exercise and heat stress - the benefits.

Athletic endurance - improves thermoregulatory function. Improves ability to remove heat through sweat.

So the less heat the less the uncomfortable feeling the more people can tolerate.

A recent study found that 30 min sauna 3 x per week significantly improved participants timed run to exhaustion.

Muscle effects.

1. Stave of muscle atrophy. Rats exposed to heat stress 30min staved off muscle atrophy during disuse due to expression of more heat shock proteins which maintained for several days after heat.

2. Improved muscle growth after disuse.

After muscle disuse for 7 days the rats exposed to 30/60 min heat stress we’re able to regrow muscle 20/30 x faster.

Mechanisms for this

  1. Robust activation of heat shock proteins - prevents degradation and scavenging free radicals that may cause damage.

  2. Growth hormone released that stimulate IGF-1 which increases protein synthesis and reduces protein degradation.

  3. Increase insulin sensitivity in muscle tissue. This decreases degradation of protein. Increase glucose transporters in muscle so improved efficiency of glucose into the muscle.

So there you have it sauna is suggested to have potential benefits for recovery, rehabilitation and overall endurance.


For those without sauna?

We talk about heat stress from the sauna here but studies have shown that 30 mins hot bath immersion can also provide similar benefits.


Remember this is only information and not medical advice. Always seek approval from your GP before trying a new stress modality especially if you have ongoing medical issues.