Tossing and turningMany mattress manufactures make claims that their beds reduce the amount of movements during the night or as they say they ‘reduce toss and turning’ (although in fact you ‘toss and turn’ when you are awake during the night not when you are asleep). However it is natural to change position during the night. Adults are reported to change their sleep position between three and 45 times per night (1,2,3,4,5) with anything up to 12 different sleep positions being used during the night (1). Videotape studies have shown that adults change their body position an average of 11 to 13 times per night (2,6) with the majority of sleep time spent lying on the side (6). One of the reasons for moving is to relieve pressure, (just think how uncomfortable you would be if you were to sit in the chair you are sitting in for 8 hours without moving) but you also change position to help you control your temperature during the night i.e. you are moving to a cooler part of the bed to assist in the reduction of body temperature that is necessary for good sleep. Moving during sleep is not related to quality of sleep as children (3-5 years), who have lots of deep sleep and thus sleep well, change position on average of 42.3 times a night whereas the elderly (65-80 years), who have much lighter more disturbed sleep, shift position an average of 16.4 times a night. (7) There are a number of factors that influence the number of movements made by an individual during a night’s sleep e.g. illnesses which affect sleep (such as sleep apnoea); caffeine and heavy meals (which increase sleep movements); alcohol (which decreases motion early in the night and increases movement during the latter half of sleep). Dreams (8); uncomfortable bedding (9); bodily comfort which as mentioned above includes body temperature; unfamiliar surroundings; noise; anxiety and stress (10) may also affect the number of movements during sleep. Now of course if a mattress reduces the amount of time you are awake during the night it may reduce the amount of wake related ‘toss and turn’ but as you can see very few of the factors influencing the number of movements during sleep can be in anyway influenced let alone ameliorated by a mattress. Let me reiterate it is natural and indeed important to be able to comfortably and easily change your body position during the night and with regards to sleep endeavouring to reduce these natural body movements is not a sensible aim.The link between sleep and tossing and turning is nicely illustrated by the following start of the night before the first manned space flight there were two possible cosmonauts Gagarin and Titov, that night they sleep in special beds, their every toss and turn monitored by strain gauges fitted to their mattresses to allow doctors to decide if they experienced restful sleep. Gagarin worked out that the person who had the best sleep would be chosen, so he stayed awake all night not moving! So a bed should allow you to make the natural movements you need without being uncomfortable and thus disturbing your sleep.Reference List1. Dunkell S (1977). Sleep positions: the night language of the body. Heinemann, London.2. Dzvonik ML, Kripke DF, Klauber M & Ancoli-Israel S (1986). Body position changes and periodic movements in sleep. Sleep 9:484-491.3. Aaronson S T, Rashed S, Biber M P & Hobson J A (1982). Brain state and body position.Archives of General Psychiatry 39:330-335.4. Johnson HM, Swan TH & Wiegand AB (1930). In what positions do healthy people sleep? J. Am. Med. Assoc. 94:2058-2062.5. De Koninck J, Gagnon P & Lallier S (1983). Sleep positions in the young adult and their relationship with the subjective quality of sleep. Sleep 6:52-59.6. Gordon SJ, Grimmer KA, Trott P (2004): Self reported versus recorded sleep position: an observational study. Internet Journal of Allied Health Sciences and Practice Vol 2:No1. 7. De Koninck J, Lorrain D & Gagnon P (1992). Sleep positions and position shifts in five age groups: an ontogenetic picture. Sleep 15:143-149.8. Hales D (1980). The complete book of sleep. Addison-Wesley Publishing Company.9. Oswald I & Adam K (1983). Get a better nights sleep, Prentice-Hall Canada Inc., Ontario.10. Kryger MH, Roth T & Dement WC (1989). Principles and practice of sleep medicine. WB Saunders Company..