The standing asanas are the yoga poses or asanas with one or both feet on the ground, and the body more or less upright. They are among the most distinctive features of modern yoga as exercise. Until the 20th century there were very few of these, the best example being Vrikshasana, Tree Pose. From the time of Krishnamacharya in Mysore, many standing poses have been created. Two major sources of these asanas have been identified: the exercise sequence Surya Namaskar (the salute to the sun); and the gymnastics widely practised in India at the time, based on the prevailing physical culture.
The origin of standing asanas has been controversial since Mark Singleton argued in 2010 that some forms of modern yoga represent a radical reworking of hatha yoga, in particular by adding standing asanas and transitions (vinyasas) between them, and by suppressing most non-postural aspects of yoga, rather than a smooth continuation of ancient traditions. These changes enabled yoga to be practised as a flowing sequence of movements rather than as static poses, and in turn this allowed sessions to focus on aerobic exercise.