Have you ever felt like a "100-year-old" after a week in bed with the flu? Well, that is not far from the truth. Muscles disappear quickly when we do not use them, but luckily, infrared sauna can significantly slow muscle loss.
As we get older, we naturally lose muscle mass, but it can also be caused by illness or injury. Although exercise can help counteract muscle loss, some medical conditions or physical limitations can make exercise difficult or impossible.
In muscle wasting (muscle atrophy), muscle tissue shrinks because the muscle cells become smaller and the muscles become weaker. We will all experience muscle loss over time, but how much and how quickly it happens depends on how well we look after our bodies and health.
Inactivity or sitting still affects many processes in the body, from the obvious, such as reduced strength and movement, to poorer mood, metabolism, circulation, fitness and quality of life.
Heat therapy prevents muscle loss
In a podcast published on Found my fitness, the renowned physician and researcher Rhonda Patrick explains how sauna use and heat therapy help preserve muscle strength. Studies show that heat therapy can have an "anti-atrophy effect".
– Researchers found that local heat therapy on muscles that were not being used prevented muscle loss by up to 40% compared with the control group. In other words, muscle loss happens regardless during inactivity, but heat therapy can slow it down.– That is big, and in line with earlier animal studies. I am glad to see the same results in humans.
How much and how fast we lose muscle strength and muscle mass when we go from an active to an inactive life has surprised even researchers.
In a Danish study, men of different ages had one foot put in a cast for 14 days. While the young men lost a third of their muscle strength and 485 grams of muscle mass, the older men lost about a quarter of their muscle strength and 250 grams of muscle mass.
This means the inactive muscles of a 20-year-old age by the equivalent of 40 to 50 years. In two weeks, the muscles in the foot "belong" to a man in his 60s.
If you are trained, you lose more muscle mass than if you are untrained. For older people, however, the loss is considered more critical, as it has a greater negative impact on health.
All the participants in the study also experienced reduced fitness.
Afterwards, the participants were to cycle 3-4 times a week for six weeks. This proved not to be enough to regain their original muscle strength. To regain muscle strength, it must be combined with strength training. It takes three times as long to get back to the starting point.
Three weeks in bed is like 30 years of ageing
Another study showed that three weeks in bed had a greater negative effect on physical fitness than 30 years of ageing. In three weeks, the participants went from having, for example, the muscles of a 40-year-old to those of a 70-year-old.
There are of course individual differences, but these are very interesting observations.
Let us use the men with casts as an example. If both legs were inactive and one was in a cast while the other received local heat therapy, the foot receiving heat therapy would lose 291 grams of muscle mass instead of the 485 grams lost by the leg without heat therapy.
Sauna gives a robust increase in heat shock proteins
In the podcast, Patrick explains that the mechanisms that prevent a greater loss of strength and muscle mass are mainly linked to the robust increase in heat shock proteins and growth hormones that occurs with induced heat stress, such as in a sauna.
Among other things, she refers to a study in which heat therapy slowed muscle loss in the hind legs of rodents by up to 32%. The rodents that received heat therapy lost significantly less muscle weight than the control group.
A small study on healthy young individuals found that 1 hour of heat therapy led to increased activity in markers that help maintain muscle mass and protect against muscle wasting.
Another study found that daily heat treatments applied locally to inactive muscles for 10 days reduced skeletal muscle loss by 37% compared with the control group. Once again, this was due to increased activity in, among other things, heat shock proteins.
The findings suggest that heat stress may serve as an effective therapeutic strategy for slowing the reduction in muscle mass that comes with periods of inactivity.
– Heat shock proteins are one of the most protective, adaptive responses to induced heat stress. Many things stimulate heat shock proteins, but heat stress raises levels markedly, and they can stay activated for 48 hours after a sauna session, Rhonda Patrick goes on to explain in the podcast.
Never too late
The reason muscles break down quickly when we are inactive is that the body adapts to its activity level. The muscles used most in everyday life are the first to go, and it happens especially fast during the first inactive week.
Researchers used to believe that the ability to build muscle had an expiry date after a certain age. This was disproved in a 1990s study in which a group of 80 to 100-year-olds started strength training and experienced a strength increase of over 100%.
It is never too late to start exercising or to make infrared sauna part of your training routine or wellness routine.
Studies show countless health benefits associated with sauna use. This is mainly due to the mechanisms that take place in the body, triggered by heat stress. Heat stress triggers many of the same processes that occur in the body when we exercise.
Infrared sauna can be a powerful tool against muscle loss. It is for everyone, but especially for those who cannot exercise regularly. Sauna can be used by athletes who are injured, by people with chronic illness, or to preserve as much muscle mass and good health as possible in general.
NB: Do not use a sauna if you have a fever. Check any contraindications under the frequently asked questions. This post is intended to share interesting observations, not medical advice. If you have conditions that make you unsure whether sauna is right for you, consult your doctor.
Disclaimer: The content of this article is intended as general information only. Research on infrared heat and red light therapy is still evolving, and individual results may vary. Our products are not intended to diagnose, treat, cure or prevent disease. Contact a doctor or other qualified healthcare professional if you have questions about your own health, diagnosis or treatment.
Text: Trine Dahlman
