- The researchers studied the effects of exercise and sauna on cardiovascular health.
- They found that exercise and sauna together are more beneficial for cardiovascular health than exercise alone.
- More research is needed to determine optimal sauna temperatures and durations for cardiovascular health in different populations.
Physical activity promotes cardiovascular health and reduces the risk of mortality. Cardiorespiratory fitness (CRF), measured by maximal oxygen consumption during maximal exercise testing, is inversely bound cardiovascular disease (CVD) and all-cause mortality.
sauna baths is a passive heat therapy used for pleasure, relaxation and well-being.
2015 investigation suggests that frequent sauna bathing is associated with a reduced risk of fatal cardiovascular outcomes and all-cause mortality. Also, an observation 2018 study found that higher levels of CRF and sauna bathing 3 to 7 times per week reduced fatal cardiovascular events and all-cause mortality compared with good CRF or frequent sauna bathing alone.
Knowing more about the combined effects of sauna and exercise on cardiovascular health could help people manage cardiovascular risk factors.
A new study from the University of Jyväskylä, Finland, conducted a randomized control trial (RCT) to compare the effects of sauna bathing and exercise with exercise alone on cardiovascular health. The researchers found that combining sauna baths with exercise improved heart health more than just exercising.
The findings were recently published in the american journal of physiology.
For the study, the researchers recruited a total of 48 male and female participants between the ages of 30 and 64. They all had a sedentary lifestylewhich the researchers defined as having a desk job and less than 30 minutes of total physical activity per week.
Each participant also had at least one cardiovascular risk factor, including:
Participants were then randomly assigned to one of three treatment groups:
- regular exercise based on guidelines and a 15-minute sauna after exercise
- only regular exercise based on guidelines
- control group
The intervention groups exercised 3 times per week for 60 minutes, including a 10-minute full-body warm-up, 20-minute resistance exerciseand 30 minutes of aerobic exercise.
Participants were evaluated throughout the trial. Primary outcomes included CRF, measured by maximal oxygen consumption, and blood pressure. Secondary outcomes included fat mass, total cholesterol levels, and arterial stiffness.
After analyzing the results, the researchers found that both intervention groups had lower fat mass and higher CRF than the control group.
However, those in the combined sauna bathing and exercise group experienced more significant increases in CRF and more significant decreases in systolic blood pressure (SBP) and total cholesterol than those in the exercise alone group.
When asked how combining sauna baths with exercise might be more beneficial for cardiovascular risk factors than exercise alone, readPhD researcher at the University of Jyväskylä in Finland and lead author of the study, said MNT:
“What we know from the literature is that the post-exercise period is what is known as a ‘window of opportunity,’ in which there is increased insulin sensitivity and reduced blood lipid levels (for no more than 60 to 90 minutes). This presents an ideal opportunity for joint interventions such as heat therapy and, in this case, sauna baths.”
“Furthermore, during the post-exercise period, angiogenic factors are elevated, and thus altering blood flow or oxygen delivery after exercise may have an additive or synergistic effect on angiogenic signaling induced by exercise alone, although this has not yet been experimentally established in humans,” he added.
Chris Minsonprofessor of human physiology at the University of Oregon, who was not involved in the study, also said MNT:
“Some of these changes were likely manifested through an increased heat shock protein (HSP) response in the [exercise and sauna group] versus the exercise group alone. HSPs are known to have many beneficial effects on blood vessel health, endothelial function, and cardiac function when upregulated. They have also been implemented in skeletal muscle function and blood volume expansion, which may have improved cardiorespiratory function.”
The researchers concluded that future research should investigate the optimal exposure durations, frequencies, modalities, and temperatures for heat exposure to benefit cardiovascular health.
When asked about the study’s limitations, Lee noted that they only investigated people with at least one cardiovascular risk factor, meaning their findings may not apply to healthy populations, athletes, or people with non-sedentary lifestyles.
Dr. Matthew S. Ganioprofessor of exercise science at the University of Arkansas, who was not involved in the study, also said MNT: “This study has a strong study design, but it would have been nice to see the independent effect of sauna use alone.”
“Interestingly, exercise alone did not lead to improvements in resting blood pressure or cholesterol compared to controls without exercise and without sauna use. Only when we compared exercise to exercise plus sauna use did we see improvements in those cardiovascular risk factors. This infers that there is something unique about sauna use that causes changes in blood pressure and cholesterol.”
– Matthew S. Ganio, PhD, professor of exercise science at the University of Arkansas
Lee noted that during the investigation, they increased the temperature of the sauna biweekly by 5 degrees Celsius to avoid a “plateau effect.”
“We can think of it from an exercise perspective; when we get fit, the same amount of exercise with the same intensity or duration would no longer be ‘stressful’ to the body, and [thus improvements stall]Lee said.
He added that you should increase the intensity, duration, or frequency of exercise to create more stress for the body to overcome, and that the same can be said for heat stress induced by sauna baths.
“I bring this up because most people who use the sauna may only have access to a publicly available one, where they may not be able to modify the temperatures,” he said. “In such cases, it may be more feasible to increase the frequency of visits over time. [going once per week for a month and then twice per week for the next month, for example- or increase the session duration- from five minutes each time for six weeks to seven minutes for the next six weeks].”
“Epidemiological data have found that greater frequency and duration of sauna use is associated with reduced risk of CVD and all-cause mortality, although frequency of sauna visits and duration of sauna bathing are still have not been experimentally tested.
– Earric Lee, PhD researcher at the University of Jyväskylä in Finland and lead author of the study
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