Varying alignment affects lower extremity joint and limb loading during yoga's triangle (Trikonasana) pose.

Background: Limited biomechanical data exist describing how yoga asanas (postures) load the limbs and joints, and little evidence-based recommendations for yoga injury prevention are available. This study aimed to establish joint loading metrics for an injury-prone, yet common yoga pose, the Triangle asana (Trikonasana) by identifying how stance width adjustments alter lower extremity loading.

Methods: Eighteen yoga practitioners underwent 3D motion analysis while performing Trikonasana with self-selected (SS) stance width and -30, -20, -10, +10, +20, and +30% of SS stance width. Ground reaction forces (GRFs), joint forces, and joint moments were calculated for the leading and trailing limb ankle, knee, and hip. One-way repeated-measures analysis of variance determined differences in loading due to stance width.

Results: GRFs, net joint forces, and net joint moments were significantly affected by stance width where increasing stance width increased leading limb loading but decreased trailing limb loading.

Conclusions: Altering stance width of Trikonasana influences lower extremity limb loading, and these loading responses were limb-dependent. Yoga practitioners and instructors can use this information to objectively support increasing or decreasing stance width to reduce or increase limb loading according to their goals or to make accommodations to groups such as beginners or at-risk populations for safer, more accessible yoga practices. Cuing a wider or narrower stance width will not have the same effect on both limbs.