Anyone who’s taken a yoga class already knows that it can reduce stress. The same holds for mindfulness-based stress reduction programs (MBSR), whose name says it all.
But what if you combined the two? Can mindfulness and yoga together provide even more stress relief?
A new study suggests no. But there are several caveats to this answer, including what you mean as “yoga.”
Study compares mindfulness and yoga for stress relief
Researchers from the University of Pennsylvania in Philadelphia set out to tease apart the benefits of mindfulness and yoga for stress relief — not an easy thing to do, because there is some overlap between the two practices.
They enrolled 60 university students — a typical high-stress group — into the study, assigning them randomly to one of four groups: mindfulness training and meditation alone, yoga alone, a combined group that did both, and a control group that didn’t receive any help with their stress.
The study was published in 2017 in the journal Mindfulness.
The mindfulness training was based on John Kabat-Zinn’s eight-week Mindfulness-Based Stress Reduction Program (MBSR), which is adapted from a Buddhist meditation practice. This study, though, included only the breathing and meditation practices, with none of the movement practices such as mindful walking, stretching, and light yoga.
The yoga classes focused on the physical aspects of yoga. Students moved through a series of traditional poses (asanas), with a focus on developing balance, core strength and flexibility. The class ended with relaxed breathing (savasana).
The mindfulness training only, yoga only, and combined groups all received similar training in breath awareness and deep diaphragmatic breathing. The control group didn’t.
These interventions lasted for four weeks. Afterwards, students underwent a stress challenge. Only 57 students completed this part of the study.
To determine the benefits of mindfulness and yoga for stress relief, researchers measured students’ heart rate variability (HRV), both at the start of the study and after the stress challenge.
Heart rate variability is a measure of the variation in time between the heartbeats. It is also an indicator of the state of your parasympathetic nervous system. This part of the autonomic nervous system controls bodily functions such as heart rate, blood pressure, breathing, and digestion.
When you are relaxed, the variation between heartbeats, or HRV, is high, meaning that your body is ready to respond to stressful situations if they arise. If you are stressed — in flight-or-fight mode — HRV is low. A consistently low HRV has been linked to depression and anxiety, as well as an increased risk of cardiovascular disease and death.
After four weeks, all three intervention groups saw decreases in self-reported anxiety and emotional discomfort compared to the control group. But HRV changed differently among these groups.
People who did yoga alone, or mindfulness and yoga together, saw improvements in HRV, compared to the control group. These two groups also had the highest HRV at rest, and showed a slight decrease during a stress challenge.
A lower HRV during stressful situations is an expected physiological response, but if it drops too low it may indicate that a person is not handling the stress well.
Researchers also found that people who only did mindfulness training had a higher HRV than the control group at rest. But it was lower than the yoga only group and lower than the mindfulness and yoga group. This suggests they were less ready to respond to stress.
However, people in the mindfulness training group were the only ones who saw an increase in HRV during the stress challenge (although this wasn’t statistically significant). “[The mindfulness training group] seemed to be the group least troubled by the stressor,” wrote the authors.
However, the researchers pointed out that it’s not clear whether it is better to have a higher HRV while at rest or a smaller drop in HRV during moments of stress.
Much overlap between traditional mindfulness and yoga
The study seems to show that combining mindfulness and yoga for stress relief doesn’t appear to offer additional benefits, at least in terms of HRV, anxiety, or emotional discomfort.
But this is where the caveats kick in.
First, the researchers found that people who did both mindfulness and yoga “seemed to enjoy that group more” than people in the yoga alone or the mindfulness training alone groups.
People in the combined group also reported practicing the skills they were learning more often than the yoga alone group.
“We deemed it unlikely that participants in [the yoga only] group would have continued to come had the intervention been offered longer or had it not been a way to fulfill a research requirement,” the authors wrote.
This is an important factor to consider when looking at long-term benefits. I have learned from my own yoga and meditation practice that the most effective practice is the one that you do regularly.
Second, while the researchers tried to compare the physical practice of yoga with the mental aspects of mindfulness training, in doing so they changed both of these practices.
Physical movements during mindfulness meditation — such as the type of walking meditation taught by Zen master and peace activist Thich Nhat Hanh — is an important part of developing mindfulness.
This is especially true for people whose minds race away from them when trying to sit still and focus on the breath. Mindful movement can help them quiet their minds and maybe eventually move onto more breath-based practices.
Also, the yoga taught to students in this study resembles the mainly physical practice that is often taught in gyms and boutique yoga studios rather than traditional yoga, which emphasizes mindfulness and meditation.
In this study, the traditional aspects of yoga were not explicitly incorporated into the yoga classes. These include mindful awareness and a deepening meditative state, which make up four of the eight limbs of yoga outlined in the Yoga Sūtras of Patañjali — pratyahara (withdrawal of the senses), dharana (concentration), dhyana (meditation), and samadhi (merging with the divine).
It would be interesting to see what would happen if mindfulness training was compared to an exercise class, or a traditional yoga class (complete with mindfulness and meditation) to an exercise only class.
The researchers recognize this need for further research. Still, the benefits of yoga for stress relief was great enough that they also called for more mindful movement — such as yoga or Tai Chi — alongside other interventions, especially when trying to help highly stressed students.
“It would seem wise to include plenty of mindful movement in stress reduction interventions aimed at college students,” they wrote.
