Movement is changed in pain. This presents across a spectrum from subtle changes in the manner in which a task is completed to complete avoidance of a function and could be both a cause and effect of pain/nociceptive input and/or injury. Movement, in a variety of forms, is also recommended as a component of treatment to aid the recovery in many pain syndromes. Some argue it may not be sufficient to simply increase activity, whereas others defend a necessity to consider how a person moves. There is unlikely to be a simple relationship between pain and movement, as both too little and too much movement could be suboptimal for the health of the tissues. The interaction between pain, (re)injury, and movement is surprisingly unclear. Traditional theories to explain adaptation in the motor system in pain are unable to account for the variability observed in laboratory and clinical practice. New theories are required. Treatments that focus on physical activity and exercise are the cornerstone of management of many pain conditions, but the effect sizes are modest. There is limited consensus when, if, and how interventions may be individualized and combined. The aim of this narrative review was to present current understanding of the interaction between movement and pain; as a cause or effect of pain, and in terms of the role of movement (physical activity and exercise) in recovery of pain and restoration of function.