A practice differs considerably from an exercise or a technique. A practice intends to develop new capacities by developing dimensions of attention and objects of attention that go beyond usual forms of consciousness. An exercise such as group work may, under certain conditions, produce a momentary experience of a new dimension, but there will not be enough inner strength of will to continue to experience that dimension. And techniques tend to be manipulative, often attempting to make something happen rather than helping others to discover what lies within their own abilities.
Source: Sardello, R (2008). Silence: The Mystery of Wholeness, Random House.