Yoga is a popular exercise and thought to be beneficial to many aspects such as mood, flexibility and balance, etc. Gait performance is a indicator of overall health and functional status. This study aims to investigate whether or not yoga instructors have a more symmetric gait pattern and better balance ability than healthy people without experience of performing Yoga. Inertial measurement units (IMUs) will be used to gather data related to gait symmetry and single leg stance balance. A comparison by four performance indexes related to gait symmetry and balance will be made to quantify the potential advantages of yoga practice.

Yoga is a form of exercise with a focus on the structural alignment of the physical body. As Yoga movements involve a complex motion of core muscles and lower limb muscles, this exercise may be beneficial for gait stability. Gait performance is a sensitive indicator of overall health and functional status, and gait impairment can lead to a high risk of falling or diminished mobility. It was hypothesized that yoga instructors may have a more symmetric gait pattern and better balance ability than healthy non-yoga controls. Impact of yoga training on gait symmetry and single leg stance balance will be investigated. Twenty five yoga instructors and twenty five age/sex-matched healthy subjects will be recruited to conduct walking and static stability tests and these subjects' gait data and body movements will be measured during the experiments by attaching inertial measurement units (IMUs) to their lower limbs and trunks. Calculation of the subjects' asymmetry of swing phases during their gait cycles will be done to evaluate the gait performance. Afterwards, subjects will conduct four different one-leg stance tests. Two balance indexes will be defined and the recorded IMU data will be applied to evaluate the subjects' balance ability. Four performance indexes will then be defined to assess gait performance and single leg stance stability to quantify the potential advantages of yoga practice.

[Yoga instructor]

Inclusion Criteria:

• overall good health and can cooperate with orders reasonably
• between the ages of 25 to 60 years old
• practicing three to six days per week and at least ten years of experience in yoga

Exclusion criteria

• limb or leg discrepancy
• history of surgery on the lower limbs or spine
• history of musculoskeletal injury over the lower back in the past six months

[Healthy control]

Inclusion Criteria:

• overall good health and can cooperate with orders reasonably
• between the ages of 25 to 60 years old
• participated in regular exercise 2 or 3 times a week

Exclusion criteria

• limb or leg discrepancy
• history of surgery on the lower limbs or spine
• history of musculoskeletal injury over the lower back in the past six months
• experience of Yoga practicing

Yoga instructor: active and highly experienced Yoga instructor

Healthy control: gender-matched healthy participants who had no experience with yoga training and participated in regular exercise 2 or 3 times a week