Schoolbag carriage : design, adjustment, carriage duration and weight : a thesis presented in fulfilment of the requirements for the degree of Doctor of Philosophy in Ergonomics at Massey University, Palmerston North, New Zealand

Mackie, Hamish William

Schoolbag carriage : design, adjustment, carriage duration and weight : a thesis presented in fulfilment of the requirements for the degree of Doctor of Philosophy in Ergonomics at Massey University, Palmerston North, New Zealand

dc.contributor.author	Mackie, Hamish William
dc.date.accessioned	2010-07-21T02:59:08Z
dc.date.available	NO_RESTRICTION	en_US
dc.date.available	2010-07-21T02:59:08Z
dc.date.issued	2006
dc.description.abstract	There is anecdotal and scientific evidence to suggest that schoolbag carriage is associated with musculoskeletal discomfort (MSD) and possibly long-term back pain. Thus schoolbag carriage is an area of concern for students, parents and both education and health professionals. A schoolbag weight limit of 10% of body weight (BW) is currently recommended. However, it is based on subjective observations rather than objective findings and does not consider other aspects of schoolbag carriage such as schoolbag design and adjustment or carriage patterns. Five studies were conducted in order to determine the effects on students' responses to schoolbag carriage of schoolbag design, adjustment, carriage duration and weight. Backpack design had a significant effect on reported musculoskeletal discomfort and choice of backpack. Schoolbag hip-belt and shoulder strap adjustment and weight significantly affected shoulder strap tension forces and shoulder interface pressure in simulated schoolbag carriage. Using activity monitoring, school students were found to spend approximately two hours carrying their schoolbags each day. This usually comprised 11-15 times per day of 8-9 minutes of carriage. Using this temporal pattern information, 16 boys (13-14 years) were exposed to a simulated school day using schoolbags weighing 0, 5, 10, 12.5 and 15% BW and an additional condition of 10% BW with tighter shoulder straps. Posture, rating of perceived exertion (RPE), muscular strain and reported ability to walk and balance were significantly affected when schoolbag load reached 10% BW. However, despite these findings, the magnitude of self reported muscular strain and MSD suggested that 15% BW may be too heavy for school students. Thus, 10% BW may be an appropriate upper schoolbag weight limit for a typical school day. Using a psychophysical approach the mean (standard deviation) maximum acceptable schoolbag weight (MASW) selected by 16 school boys (13-14 years) was 10.4(3.8) %BW. This finding agrees with the findings of the previous study and supports the current schoolbag weight recommendation of 10% BW. The results of the five studies can be used in developing schoolbag carrying guidelines to help reduce the prevalence of MSD amongst school students.	en_US
dc.identifier.uri	http://hdl.handle.net/10179/1478
dc.language.iso	en	en_US
dc.publisher	Massey University	en_US
dc.rights	The Author	en_US
dc.subject	School bags	en_US
dc.subject	Ergonomics	en_US
dc.subject	Human engineering	en_US
dc.subject	High school students	en_US
dc.subject	Physiology	en_US
dc.subject	Lifting and carrying	en_US
dc.subject.other	Fields of Research::320000 Medical and Health Sciences::321200 Public Health and Health Services::321201 Environmental and occupational health and safety	en_US
dc.title	Schoolbag carriage : design, adjustment, carriage duration and weight : a thesis presented in fulfilment of the requirements for the degree of Doctor of Philosophy in Ergonomics at Massey University, Palmerston North, New Zealand	en_US
dc.type	Thesis	en_US
massey.contributor.author	Mackie, Hamish William
thesis.degree.discipline	Ergonomics	en_US
thesis.degree.grantor	Massey University	en_US
thesis.degree.level	Doctoral	en_US
thesis.degree.level	Doctoral	en
thesis.degree.name	Doctor of Philosophy (Ph.D.)	en_US