The phrase "restless sleepers" refers to people who have trouble sleeping calmly and peacefully. They often move around a lot and experience difficulty in getting a good night's rest. Full definition
, reflux or any other medical conditions, sleep or bedtime routine, use of a pacifier, still or restless sleeper etc.. (intelligentmother.com)
This factor is important if you're a particularly restless sleeper (or have a history of falling off beds...) but most mattresses should be pretty decent in this department. (mattressadvisor.com)