by Baxter
The Three Ages of Men by Giorgione |
I am always excited to have good news to share with my male students about how yoga can improve their health, and when recently I learned about a study done in India that looked at yoga’s potential beneficial effects on aging for healthy men, I decided to check it out! I first read about the study “Age-related changes in cardiovascular system, autonomic functions, and levels of BDNF of healthy active males: role of yogic practice” on a web site. (I’ll get to what BDNF is in minute!) The web site discussed the findings of the study, but only positive information about the study presented and there was no mention of any limitations of how the study was done or whether its design would allow for us to draw comparisons to large groups of adults doing yoga. To me, this was a bit of a red flag. On the one hand, I was excited to see a study done that was checking blood chemicals, EKGs, and other signs of stress related to aging. Because I wanted to know more about the study, such as the actual number of participants and how long they were followed and if there was any long term follow up, I went the source, the actual paper itself. (Although you can’t access the paper yourself, you can find the abstract here.)
Meditation: Total of 8 minutes
But the limitation that they did not mention is that we only know what the effect was at the end of three months of practice. We don’t know if these beneficial findings would be persistent at 6 or 12 months, let alone after 1, 2, or even 5 years. And would there be any persistent benefits if someone lapsed in their yoga practice or only did yoga two times a week? As with almost any yoga study I read these days, I am on the one hand encouraged by the positive results of this one for giving healthy men some compelling reasons to take up yoga, and on the other hand am reluctant to sound the horns of triumph until larger follow-up studies support these initial findings. And that, sadly, costs a lot of money to do! Any billionaires out there looking to support some good works in the world?
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The first sentences of the abstract for the study gave me a good starting point on why the researchers were doing the paper. My translations of the scientific language into more accessible terms are in brackets.
“Aging is associated with decline in cardiovascular, autonomic function, and brain-derived neurotropic factor (BDNF). [this is what we know from present research on aging] Reports are scanty regarding whether yoga can improve age-related degenerative changes in healthy active men. [this is what we don’t know yet] This study is designed to appraise the role of yoga in improving age-related degenerative changes in cardio-metabolic risk profile, autonomic function, stress, and BDNF. [this is what scientists plan to look at]
And I have to say that these researchers checked a lot of stuff in the participants to assess their goals—quite impressive! But how did they choose the men in the study? These were their criteria:
“Inclusion criteria included (1) normal healthy and physically active male; (2) absence of disease which could have contributed to obesity, hypertension, and neurological disorders; (3) not on medication; (4) no prior knowledge of yoga; and (5) smokers, alcoholics, and tobacco eaters (in India, where the study was done, they eat tobacco!) were excluded from study.”
This seems reasonable: healthy, active men who have not done yoga before. However, one immediate problem was the small number of men in the study, only 60 in total. The authors looked at three groups of healthy men, 20 in each group, with age ranges of 20-29, 30-39, and 40-49. This is a concern because the smaller the numbers of participants, the less compelling the results of any study are.
In studying this group, the scientists checked a variety of data related to aging, including blood tests for quite a number of markers, such as cortisol, and a brain substance called BDNF, or brain-derived neurotropic factor, which normally drops as we age. (BDNF is a key mediator of neuronal plasticity in adult, adult neurogenesis, and brain aging.) “Blood samples were collected in the morning after overnight fasting before and after 3 months yogic practice for biochemical estimation.” And the results are quite encouraging! Heart-, metabolic-, and neurologic-related aging changes were better in their study group.
So how much yoga and what kind of practices were these men doing? I was curious about what the yoga practice looked like: was it a simple beginner practice, and was it well rounded in poses, breath work and meditation?
According to the paper, “In addition to their routine activities, participants practiced one hour of yoga for 3 months in the morning with ambient temperature under supervision of qualified yoga instructor.” And here is what they did:
Table 2 Details of yogic module
Cleansing processes (2 min)
Table 2 Details of yogic module
Cleansing processes (2 min)
Kapalbhati (Rapid shallow breathing)
Yogasanas (yogic postures): Total of 40 minutes
Suryanamaskar (sun salutation in 12 different postures, 1 round)
Padmasana
Yogamudra
Matsayasana
Suptapavanmuktasana
Pavanmuktasana
Paschimottanasana
Vajrasana
Suptavajrasana
Gomukhasana
Sarvangasana
Halasana
Karnapedasana
Bhujangasana
Shavasana (relaxed supine posture)
Pranayama (breathing exercises): Total of 10 minutes
Bhastrika (forceful expulsion of breathing)
Anulom-vilom (alternative nostril breathing)
Bhramri (producing buzzing sound of bee with closed ear and lips)
Meditation: Total of 8 minutes
Omkar meditation (Om Chant)
Total session 60 minutes.
Although this protocol includes poses, breath work and meditation—a good balance—I’m concerned about the poses they practices, which are all symmetrical poses and are either forward bends or backbends, with no twists or side bends included. And many of the poses are intermediate ones, which someone unfamiliar with yoga might have trouble with, such as full Lotus, Shoulderstand and variations, and Reclined Thunderbolt pose, to name the most obvious. This could limit the applicability of this particular practice for the general population.
Total session 60 minutes.
Although this protocol includes poses, breath work and meditation—a good balance—I’m concerned about the poses they practices, which are all symmetrical poses and are either forward bends or backbends, with no twists or side bends included. And many of the poses are intermediate ones, which someone unfamiliar with yoga might have trouble with, such as full Lotus, Shoulderstand and variations, and Reclined Thunderbolt pose, to name the most obvious. This could limit the applicability of this particular practice for the general population.
To their credit, the authors do cite some of the limitations of the study, including the lack of control group (a control group is a similar number of healthy active men that did not do yoga and were evaluated with the same tests-this study does not have one):
“The present study suffers from some limitations that need to be acknowledged and addressed. One of these is the relatively small sample size in each group. An additional limitation is that this study is a single-arm study without any separate control group.”
And their final conclusion is also fairly accurate:
“Based on the results of the present study, it may be concluded that the aging process has an active role on degenerative changes in cardio-metabolic risk factors, autonomic functions, and monoamines as well as levels of BDNF, which may revert back towards normal or near-normal levels through yogic practice in healthy active males. (bold is mine)”
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