Physical manifestation of situations and patterns in attitude
Dancers and singers clear their karma with their art. This is because the energies present in their bodies is expended through their art. Vigorous/rhythmic shaking of the body for example pulls and pushes energy in different directions. This is a quicker way of expending stored and stuck energies from your self, making way for newer and fresher energies which wipe out stored karmas as well as take you onward to your path of spiritual growth.
The other way, described in an earlier post is, through doing your duties systematically, through the 80:20 principle for example, so whatever is inside you is spent, your fixed and negative patterns are changed and your attitudinal lessons are learnt. This way your body (ethereal body) opens up to receive newer energies from the Universe.
A faster quicker way is to sing and dance. Dance probably is more effective. But singing too. Its no wonder artistes reach heights of spiritual ecstasy through devotional singing and dancing. Krishna bhaktas for example, dance in abandon to Krishna dhuns, Osho meditation is through dance too. In religion and spirituality one can find innumerable examples of the energizing effects of such art forms.
Prayer, chanting too, in the same vein, clears your karmas. All religions do say that taking Gods name is the surest way of overcoming bad karma.
Using this logic, one can extend this benefit to sports and the playfield as well. I would say Sports would have limited benefit for karma clearing, unless accompanied by clear spiritual intentions. Generally sportsmen and women are people of great moral values and positive beliefs, acquired partly through expending energies through physical exercise.
Yoga, of course is one of the greatest of all paths to spirituality and karma cleaning.
This is a suggestion for those who have reached their path to start their journeys. Their methods will be shown to them. Of course nothing will work, till your time has come.