title: Impact of backpack type on respiratory muscle strength and lung function in children.
abstract: We examine the influence of backpack type on lung function and respiratory muscle strength in children. Thirty-seven children were assessed for lung function and inspiratory and expiratory muscle strength under four randomly determined conditions: unloaded erect standing and three conditions carrying 15% of the child's body weight. In these three conditions, children carried the weight on a backpack with bilateral shoulder straps carried over both shoulders, on a backpack with bilateral shoulder straps carried over one shoulder and on a backpack with a mono shoulder strap. Significantly lower forced vital capacity, forced expiratory volume in one second and maximal expiratory pressure were observed when children carried a backpack with a mono shoulder strap compared to the unloaded standing position. In conclusion, the restrictive effect and the decrease in expiratory muscle strength were more pronounced for the backpack with a mono shoulder strap, suggesting that a double strap backpack is preferable to a mono shoulder strap backpack. Practitioner summary: There is little known about the effect of schoolbags on respiratory muscle function. We investigated the influence of backpack type on lung function and respiratory muscle strength. A backpack with a mono shoulder strap created a restrictive effect and a decrease in strength, suggesting that a double strap backpack is preferable to a mono shoulder strap backpack.
authors.affiliation: a Polytechnic Health Institute of the North , CESPU , Grandra (PRD) , Portugal.
authors.forename: Ana Christina
authors.initials: AC
authors.lastname: Vieira
authors.forename: Fernando
authors.initials: F
authors.lastname: Ribeiro
mesh_terms: D001415:Back; D002648:Child; D004867:Equipment Design; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D053580:Muscle Strength; D011187:Posture; D011312:Pressure; D012129:Respiratory Function Tests; D012132:Respiratory Muscles; D012782:Shoulder; D014797:Vital Capacity; D016474:Weight-Bearing
keywords: child; maximal expiratory pressure; maximal inspiratory pressure; pulmonary function; schoolbag type