Physiotherapists are well placed to help people adjust and engage meaningfully with the world following major weight loss. Recent research indicates that the body size a patient has lived with for years can continue to affect movement and perception even after largescale weight loss. This article explores this discrepancy in depth from the perspective of phenomenology and space perception and through the concepts of body image, body schema, and affordances. It draws on an empirical example in which a nautical engineer described his lived experience of returning to work following bariatric surgery and the discrepancies he experienced while adjusting to his new situation, particularly when moving his smaller body around the ship's engine room, previously inaccessible to him. Analysis of this empirical example suggests that transitions in weight and size following bariatric surgery are both highly explicit in awareness (i.e., body image) and outside awareness (i.e., body schema). Major weight loss can open up new affordances and possibilities of being in the world, but only after adjustments in body image and body schema. The article suggests ways in which such insights can contribute to physiotherapists' clinical development and practice when working with patients undergoing major weight loss.