March 2021 Issue

Focus on Fitness: Yoga Research Update
By Jennifer Van Pelt, MA
Today’s Dietitian
Vol. 23, No. 3, P. 52

Recent scientific research on yoga has been vigorous—hundreds of studies have been published just within the last two years describing health benefits for a wide range of medical conditions. Yoga now is being adopted by health care practitioners and facilities as part of some disease management and wellness programs.

But many people still have a negative perspective about yoga, stemming primarily from its depiction in the media. Yoga pose images posted by very fit people on social media and the media’s depiction of yoga practitioners as thin, young, and very healthy imply that yoga is for only fit people. Because of this portrayal, many individuals, especially those with chronic medical conditions, believe yoga is beyond their physical capabilities and decide not to try it. The scientific and medical research community is hoping to change those perceptions through investigating yoga’s potential in disease management.

Areas of Research
One of the most researched medical applications of yoga is for anxiety relief. In November 2020, a systematic review and meta-analysis of 24 studies that compared yoga with nonmindful exercise (eg, aerobic exercise, strength training) in a nonmedical setting was published. The researchers found that yoga was more effective in reducing anxiety than nonmindful exercise and suggested that yoga be considered by the primary care community for reducing anxiety in the general public, possibly as an alternative to medications.1

Another research focus for yoga has been its use as adjunctive therapy for cancer patients to help alleviate symptoms of fatigue, chronic pain, and anxiety/depression associated with cancer treatment. Studies published in 2020 that further confirm benefits for cancer patients include the following:

• A June 2020 randomized controlled study assessed the effects of eight weeks of yoga for 41 survivors of breast and gynecological cancers with moderate to severe chemotherapy-induced peripheral neuropathy, a common side effect of cancer treatment that increases fall risk and reduces quality of life. The yoga intervention focused on breathing, musculoskeletal strength and flexibility, and balance, and involved twice-weekly in-person group classes and at-home yoga with a study-provided video on three other days. In comparison with those treated with usual care, those doing yoga had decreased pain and showed improvements in functional measures related to fall risk. In comparison, the group treated with usual care had fewer improvements in pain and increased risk of falls.2

• A July 2020 randomized controlled study investigated the effect of yoga on quality of life in 100 breast cancer patients undergoing chemotherapy. Patients in the yoga group were taught breathing techniques, relaxation, and neck/shoulder poses to practice twice daily at home throughout six cycles of chemotherapy. Yoga was found to improve quality of life, as well as physical and emotional functioning; patients doing yoga also reported fewer symptoms of fatigue.3

• An October 2020 study evaluated the effects of eight weeks of yoga therapy (60 minutes per session, once weekly) on fatigue in 173 cancer patients. In comparison with a control group, those who did yoga reported statistically significant decreases in general fatigue, physical fatigue, and depression, as well as a significant increase in quality of life. Women with breast cancer reported a greater reduction in fatigue while practicing yoga than those with other types of cancer.4

The following research suggests that yoga also may benefit those with rheumatoid arthritis by improving some functioning and reducing fatigue:

• A November 2020 systematic review and meta-analysis evaluated the effect of yoga in 10 studies that included 840 patients with rheumatoid arthritis. The analysis showed that yoga significantly improved physical functioning, disease activity, and grip strength. However, it had no effect on pain, tender/swollen joints, or inflammation.5

• A December 2020 randomized controlled study evaluated yoga (two 90-minute sessions weekly for 12 weeks) in comparison with arthritis education (once-weekly 60-minute program) in 57 patients with rheumatoid arthritis. Although no significant differences were noted in health-related quality of life and disease activity, yoga did result in significantly greater improvements in fatigue and mood.6

Because of its evidence-supported benefits for helping fatigue symptoms in other diseases, yoga was studied in a November 2020 randomized controlled trial as a treatment alternative for veterans with Gulf War illness, a difficult-to-treat condition characterized by chronic symptoms including pain, fatigue, and mood/cognitive issues. In this trial, 75 patients were randomized to do 10 weekly group sessions of either yoga or cognitive behavioral therapy (CBT). Pain severity decreased in the yoga group but not in the CBT group, while fatigue was significantly reduced in the yoga group compared with the CBT group. Based on the positive results of this trial, yoga is being incorporated into Gulf War illness management and evaluated further as a potential treatment.7

Also published in November 2020 was the first meta-analysis on yoga and other mindfulness therapies (eg, meditation) for the treatment of mild traumatic brain injury (TBI). The researchers analyzed 20 studies with a total of 539 participants with mild TBI who practiced yoga, meditation, and other mindfulness-based activities. Compared with control groups, those practicing yoga and other mindfulness therapies showed significant improvement in overall symptoms, mental and physical health, cognitive performance, quality of life, fatigue, and depression. Of note, the greatest improvements were related to fatigue and depression, suggesting that yoga and mindfulness therapies could be an alternative to medications prescribed for these TBI symptoms.8

Yoga research has reached the point that systematic reviews and meta-analyses for several indications are now possible to validate the conclusions of individual studies, and the investigations discussed here represent only a few. Numerous other studies reported yoga as beneficial for those with multiple sclerosis, schizophrenia, COPD, HIV, posttraumatic stress disorder, chronic pain, and more. It’s clear from recent research that yoga isn’t just for the healthy and fit; it can be applied and modified to help improve symptoms for a range of medical conditions and levels of physical functioning.

— Jennifer Van Pelt, MA, is a certified group fitness instructor and health care researcher in the Lancaster, Pennsylvania, area.


1. So WWY, Lu EY, Cheung WM, Tsang HWH. Comparing mindful and non-mindful exercises on alleviating anxiety symptoms: a systematic review and meta-analysis. Int J Environ Res Public Health. 2020;17(22):8692.

2. Bao T, Zhi I, Baser R, et al. Yoga for chemotherapy-induced peripheral neuropathy and fall risk: a randomized controlled trial. JNCI Cancer Spectr. 2020;4(6):pkaa048.

3. Prakash K, Saini SK, Pugazhendi S. Effectiveness of yoga on quality of life of breast cancer patients undergoing chemotherapy: a randomized clinical controlled study. Indian J Palliat Care. 2020;26(3):323-331.

4. Zetzl T, Renner A, Pittig A, Jentschke E, Roch C, van Oorschot B. Yoga effectively reduces fatigue and symptoms of depression in patients with different types of cancer [published online October 7, 2020]. Support Care Cancer. doi: 10.1007/s00520-020-05794-2.

5. Ye X, Chen Z, Shen Z, Chen G, Xu X. Yoga for treating rheumatoid arthritis: a systematic review and meta-analysis. Front Med (Lausanne). 2020;7:586665.

6. Pukšić S, Mitrović J, Čulo MI, et al. Effects of Yoga in Daily Life program in rheumatoid arthritis: a randomized controlled trial [published online December 8, 2020]. Complement Ther Med. doi: 10.1016/j.ctim.2020.102639.

7. Bayley PJ, Schulz-Heik RJ, Cho R, et al. Yoga is effective in treating symptoms of Gulf War illness: a randomized clinical trial [published online November 11, 2020]. J Psychiatr Res. doi: 10.1016/j.jpsychires.2020.11.024.

8. Acabchuk RL, Brisson JM, Park CL, Babbott-Bryan N, Parmelee OA, Johnson BT. Therapeutic effects of meditation, yoga, and mindfulness-based interventions for chronic symptoms of mild traumatic brain injury: a systematic review and meta-analysis [published online November 2, 2020]. Appl Psychol Health Well Being. doi: 10.1111/aphw.12244.