8 weeks program transcends the life of the healthier people, reveal studies. However, clinically, there is no evidence to quantify the amount of mediation training that is effective to release stress. Studies focusing on self-assessment may not predict the effectiveness of mediation training precisely.
“The participants know that they are ingesting the ‘antidote’,” says Puhlmann. “In mindfulness research, we are therefore increasingly using more objective, i.e., physiological, methods to measure the stress-reducing effect more precisely.”
Hair containing more cortisol concentration denotes a sizeable measure of exposure to prolonged stress. Cortisol is a stress hormone that is released when we are confronted with a difficult situation. It assists us in putting our bodies on alert and mobilizing energy to overcome the challenge in that situation. The longer we are stressed, the more cortisol is produced and circulated throughout our bodies, and the more it accumulates in our hair.
Hair grows one centimeter per month on average. The researchers, in collaboration with Clemens Kirschbaum’s working group at the University of Dresden, analyzed the amount of cortisol in the first three centimeters of the hair every three months to measure the study participants’ stress levels during the 9-month training.
The ReSource project, led by Prof. Dr. Tania Singer, scientific director of the Social Neuroscience Research Group, developed mental training as part of a large-scale longitudinal study on the effects of mental training. This nine-month mental training program was broken down into three three-month sessions, each focusing on a different skill area through Western and Far Eastern mental exercises. The emphasis was either on factors like attention and mindfulness, socio-affective skills like compassion and gratitude, or so-called socio-cognitive skills like the ability to put one’s own and others’ thoughts into perspective.
The training modules have all been completed in a different order by three groups of about 80 participants. The training lasted up to nine months but rather depended on 30 minutes of training per day, six days a week. And it was conspicuous: “After six months of training, the amount of cortisol in the subjects’ hair had decreased significantly, on average by 25 percent. In the first three months, slight effects were seen at first, which increased over the following three months. In the last third, the concentration remained at a low level. “
The researchers thereby proposed that long-term meditation training yielded stress reduction regardless of the mental approaches in the mental training content as all the approaches had a similar effect in improvizing the people’s stress management skills.
The researchers analyzed the effects of training on dealing with acutely stressful situations in a past analysis from the ReSource project with the same sample. The study participants were placed in a stressful job interview and had to solve difficult math problems while being observed. The findings revealed that people who had received socio-cognitive or socio-affective training released up to 51% less cortisol during tense events than those who had not. They didn’t measure cortisol levels in the subjects’ hair in this case, but rather acute cortisol surges in their saliva.
“We assume that different training aspects are particularly helpful for these different forms of stress,” says Veronika Engert, head of the research group “Social Stress and Family Health” at MPI CBS.
“There are many diseases worldwide, including depression, that are directly or indirectly related to long-term stress,” explains Puhlmann. “We need to work on counteracting the effects of chronic stress in a preventive way. Our study uses physiological measurements to prove that meditation-based training interventions can alleviate general stress levels even in healthy individuals.”