Doing yoga on a regular basis can cause musculoskeletal pain or worsen injuries you already have. Here are some ways to reduce the risks.

You may want to think twice before trying the Downward Dog.

Yoga as a form of exercise may not be quite as safe as previously thought.

A recent study published in the Journal of Bodywork and Movement Therapies found that yoga causes musculoskeletal pain in 10 percent of people, and exacerbates 21 percent of existing injuries.

“The study found that most ‘new’ yoga pain was in the upper extremities [shoulders, elbows, wrists, hands] possibly due to Downward Dog and similar postures that put weight on the upper limbs,” Evangelos Pappas, PhD, an associate professor of musculoskeletal physiotherapy at The University of Sydney in Australia and lead researcher of the study, said in a press release.

“In terms of severity, more than one-third of cases of pain caused by yoga were serious enough to prevent yoga participation and lasted more than three months,” he added.

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The researchers surveyed a total of 354 people who took at least one yoga class from one of two yoga studios in New York. About 95 percent of the participants were women, and averaged 45 years of age.

Each participant completed a questionnaire at the start of the study detailing their musculoskeletal pain.

After a year, the researchers then contacted the participants to assess the impact of yoga on muscle, bone, and joint pain.

Nearly 87 percent of participants reported pain within a year, and more than 10 percent said yoga had caused pain in their hand, wrist, shoulder, or elbow.

“It’s not all bad news, however, as 74 percent of participants in the study reported that existing pain was improved by yoga, highlighting the complex relationship between musculoskeletal pain and yoga practice,” Pappas said.

The 5,000-year-old practice of yoga has been gaining popularity in the United States in recent years.

A 2016 study conducted by the Yoga Alliance and Yoga Journal found the number of people who practice yoga in the United States grew to more than 36 million in 2016. In addition, 28 percent of Americans said they had participated in a yoga class at some point in their lives.

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Staffan Elgelid, PhD, a yoga therapist and an associate professor in physical therapy at Nazareth College in Rochester, N.Y., said yoga carries the same risks as other forms of exercise.

“If you take the same group of people and start them on a running, swimming, lifting, or any other form of exercise program, I think the percent of injuries would be similar or higher. The big problem is that yoga is billing itself as safe,” Elgelid told Healthline.

“I think one reason we are seeing more people complain of pain is that more and more people are turning to yoga for issues with pain that have not been resolved by allopathic medicine,” he added. “One big problem with that is that many … yoga teachers do not have their clients fill out a medical history form, so the teacher has no idea if the student has any musculoskeletal issues or not, and therefore cannot modify the practice accordingly.”

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Elgelid suggests anyone who intends to start yoga for a medical or musculoskeletal reason should begin with private classes in order to be properly taught how to modify exercises for their own needs.

This is a view reinforced by the American Academy of Orthopaedic Surgeons (AAOS).

“Yoga is considered safe if approached with safety,” Dr. Jennifer M. Weiss, an orthopedic surgeon and spokesperson for the AAOS, told Healthline.

Weiss said there are several steps people can take to ensure they are practicing yoga safely.

“If you have limitations, do not push beyond them, and request modifications. Communicate with your teacher before class to understand modifications. If something does not feel right, stop. Any yoga pose can be substituted with a comfortable resting position allowing you the opportunity to stop and breathe,” she said.

Rachel Krentzman is a physical therapist and yoga instructor based in San Diego, and has been using yoga in conjunction with physical therapy for more than 15 years. She says it’s crucial to find a good yoga instructor.

“Students should inquire about the training of the yoga teachers they choose, and make sure that they are practicing a style of yoga that is suited to their physical condition,” she told Healthline.

According to the Mayo Clinic, yoga is considered “safe for most healthy people if under the guidance of a trained instructor.”

If practiced properly, the benefits of yoga include stress reduction, improvement of fitness, and management of chronic conditions.

“The key is to find a teacher who has a good working knowledge of the body, injury management and prevention, as well as proper alignment in the yoga postures,” Krentzman said.