Many people have heard of mind over body but few have appreciated the power of body over mind.
There are things of the mind which we have limited direct control over (like emotions) but which are easily affected by our postures and gestures.
We can change our mood through changing our body language.
Therefore in meditation, part of the training to tame the mind comes from correcting our posture when we walk, when we stand, when we sit and when we sleep.
Doing Taichi, yoga asanas, dance and certain other forms of kungfu & exercise can help improve our meditation.