Yoga Wedges provide support in poses when we can’t quite get our hands or feet flat on the floor. This is usually due to stiff ankles and wrists. By placing a yoga wedge under our hands and feet we improve our stability within the pose and it allows us to achieve proper alignment without undue stress and strain on those joints.
Another time when we might choose to use a wedge would be in forward folds. A slight lift of the sit bones allows us to fold forward more easily. This lift can be achieved by sitting on a bolster, a block, a folded yoga blanket, or by using a wedge. The prop you choose will depend on the amount of height you desire in the pose you are in. For example, folding forward while sitting cross-legged may be more comfortable with some added height (like a bolster or block), but folding forward with legs extended straight (Staff Pose) may require just a slight lift that you would get from a blanket or a wedge.
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