Respiratory alkalinization and posterior cerebral artery dilatation predict acute mountain sickness severity during 10 h normobaric hypoxia.

NEW FINDINGS: What is the central question of this study? The pathophysiology of acute mountain sickness (AMS), involving the respiratory, renal and cerebrovascular systems, remains poorly understood. How do the early adaptations in these systems during a simulated altitude of 5000 m relate to AMS risk? What is the main finding and its importance? The rate of blood alkalosis and cerebral artery dilatation predict AMS severity during the first 10 h of exposure to a simulated altitude of 5000 m. Slow metabolic compensation by the kidneys of respiratory alkalosis attributable to a brisk breathing response together with excessive brain blood vessel dilatation might be involved in early development of AMS. ABSTRACT: The complex pathophysiology of acute mountain sickness (AMS) remains poorly understood and is likely to involve maladaptive responses of the respiratory, renal and cerebrovascular systems to hypoxia. Using stepwise linear regression, we tested the hypothesis that exacerbated respiratory alkalosis, as a result of a brisk ventilatory response, sluggish renal compensation in acute hypoxia and dysregulation of cerebral perfusion predict AMS severity. We assessed the Lake Louise score (LLS, an index of AMS severity), fluid balance, ventilation, venous pH, bicarbonate, sodium and creatinine concentrations, body weight, urinary pH and cerebral blood flow [internal carotid artery (ICA) and vertebral artery (VA) blood flow and diameter], in 27 healthy individuals (13 women) throughout 10 h exposures to normobaric normoxia (fraction of inspired O2 = 0.21) and normobaric hypoxia (fraction of inspired O2 = 0.117, simulated 5000 m) in a randomized, single-blinded manner. In comparison to normoxia, hypoxia increased the LLS, ventilation, venous and urinary pH, and blood flow and diameter in the ICA and VA, while venous concentrations of both bicarbonate and creatinine were decreased (P < 0.001 for all). There were significant correlations between AMS severity and the rates of change in blood pH, sodium concentration and VA diameter and more positive fluid balance (P < 0.05). Stepwise regression found increased blood pH [beta coefficient (ß) = 0.589, P < 0.001] and VA diameter (ß = 0.418, P = 0.008) to be significant predictors of AMS severity in our cohort [F(2, 20) = 16.1, R2  = 0.617, P < 0.001, n = 24], accounting for 62% of the variance in peak LLS. Using classic regression variable selection, our data implicate the degree of respiratory alkalosis and cerebrovascular dilatation in the early stages of AMS development.

Age-Related Differences in Perceived Exertion While Walking and Running Near the Preferred Transition Speed.

PURPOSE: To investigate whether youth and adults can perceive differences in exertion between walking and running at speeds near the preferred transition speed (PTS) and if there are age-related differences in these perceptions. METHODS: A total of 49 youth (10-12 y, n = 21; 13-14 y, n = 10; 15-17 y, n = 18) and 13 adults (19-29 y) completed a walk-to-run transition protocol to determine PTS and peak oxygen uptake. The participants walked and ran on a treadmill at 5 speeds (PTS-0.28 m·s-1, PTS-0.14 m·s-1, PTS, PTS+0.14 m·s-1, PTS+0.28 m·s-1) and rated perceived exertion using the OMNI Perceived Exertion (OMNI-RPE) scale. Oxygen consumption was measured during the walk-to-run transition protocol to obtain the relative intensity (percentage of peak oxygen uptake) at PTS. OMNI-RPE scores at all speeds and percentage of peak oxygen uptake at PTS were compared between age groups. RESULTS: The 10- to 12-year-olds transitioned at a higher percentage of peak oxygen uptake than adults (64.54 [10.18] vs 52.22 [11.40], respectively; P = .035). The 10- to 14-year-olds generally reported higher OMNI-RPE scores than the 15- to 17-year-olds and adults (P < .050). In addition, the 10- to 14-year-olds failed to distinguish differences in OMNI-RPE between walking and running at PTS and PTS+0.14 m·s-1. CONCLUSIONS: Children aged 10-14 years are less able to distinguish whether walking or running requires less effort at speeds near the PTS compared with adults. The inability to judge which gait mode is less demanding could hinder the ability to minimize locomotive demands.

Tertiary education in ergonomics and human factors: quo vadis?

In 2019, the Human Factors and Ergonomics (HFE) discipline turned 70; to celebrate, an international group of academics and educators have reflected on the status of HFE tertiary education across the globe. This paper draws on presentations and discussions from the 20th Triennial International Ergonomics Association (IEA) conference and considers the implications for HFE education programmes. Past, current, and future challenges are outlined and discussed with examples from different countries and programmes. This paper builds on 2012 strategy proposed by Dul and colleagues, to strengthen the demand, and application, of the HFE discipline and profession. It provides a considered set of reflections, noting the range of structural issues and financial pressures within the tertiary education system that create challenges for the viability of specialist programmes such as HFE. A need exists for the broader profession to collaborate and share innovations in HFE programme development, to ensure sustainable HFE education programmes. Practitioner summary: A range of structural issues and financial pressures exist within the tertiary education system that creates challenges for the viability of specialist programmes such as HFE. A need exists for the broader profession to collaborate and share innovations in HFE programme development, to ensure sustainable HFE education programmes. Abbreviation: HFE: Human Factors and Ergonomics; IEA: International Ergonomics Association; CIEHF: Chartered Institute of Ergonomics & Human Factors; UX: User Experience; CREE: Centre for Registration of European Ergonomist; BRICSplus: Brazil, Russia, India, China and South Africa; MOOCS: Massive Open Online Courses; STST: socio technical systems theory; LMIC: low and middle-income countries.

Interaction between physical and psychosocial risk factors on the presence of neck/shoulder symptoms and its consequences.

This study aimed to quantify the interaction between physical and psychosocial factors on the presence of neck/shoulder symptoms (NSS) and its consequences (reduced activities and absenteeism) among 1294 coal mining workers in Indonesia. A self-administered questionnaire was used to obtain information on current workplace exposure and NSS and its consequences. Participants were grouped into one of four combination exposure groups: low physical and low psychosocial (as the reference group); low physical and high psychosocial; high physical and low psychosocial, and high physical and high psychosocial (HPhyHPsy). The attributable proportion (AP) due to interaction between both factors was examined. Individuals in the HPhyHPsy group were most likely to report NSS [odds ratio (OR) 4.83, 95% confidence interval (CI) 2.43-9.58], reduced activities (OR 3.90, 95% CI 2.36-6.43), and absenteeism (OR 3.91, 95% CI 2.11-7.25). This study has shown an interaction between physical and psychosocial factors that increases the OR of NSS (AP 0.49, 95% CI 0.08-0.89). Practitioner Summary: Although physical and psychosocial factors are known to be predictors for NSS, little is known about their interaction. Self-reported questionnaire was used to obtain information about physical and psychosocial factors at work. This study found an interaction between the physical and psychosocial risk factors that increases the odds ratio of NSS.

Prevalence of low back symptoms and its consequences in relation to occupational group.

BACKGROUND: The purpose of this study was to examine: (1) the prevalence of low back symptoms (LBS) and its consequences (reduced activities and absenteeism); (2) the association between occupational group and LBS; and (3) the association between LBS and its consequences. METHODS: A self-administered questionnaire was used to determine the prevalence of LBS in 1,294 Indonesian coal mining workers. A Cox proportional hazards model was developed to quantify the 12-monthly hazard of LBS. Logistic regression models were developed to identify risk factors for reduced activity and absenteeism from the workplace. RESULTS: The 12-month period prevalence for LBS, reduced activities, and absenteeism were 75%, 16%, and 13%, respectively. The 12-monthly hazard of LBS for blue-collar workers was 1.85 (95% CI: 1.06-3.25) times that of white-collar workers. LBS and smoking increased the risk of reduced activity and absenteeism. CONCLUSIONS: Indonesian coal mining workers have a high prevalence of LBS. The findings imply that efforts to reduce LBS and in the workplace should focus on blue-collar workers. For smokers who report reduced activities and/or absenteeism, there should be a focus on rehabilitation and/or return-to-work programs.

Gender differences in work-related risk factors associated with low back symptoms.

The prevalence of low back symptoms (LBS) in many working populations is high and differences in prevalence between genders are inconsistent. However, gender-specific risk factors for LBS have seldom been examined. Hence, the aim of the present study was to indicate gender-specific LBS risk factors. A sample of 3003 people was interviewed by telephone to get information about current workplace exposure and LBS. The risk of LBS for the whole population increased with work in awkward/tiring positions (OR 1.37, 95% CI 1.12-1.68) and very/extremely stressful jobs (OR 1.46, 95% CI 1.05-2.03). None of the explanatory variables were significantly associated with LBS for males but working in awkward/tiring positions (OR 1.51, 95% CI 1.04-2.20), dissatisfaction with contact and cooperation with management (OR 1.68, 95% CI 1.02-2.78) and finding their job to be very/extremely stressful (OR 2.27, 95% CI 1.46-3.52) were significantly associated with LBS for females. Interventions to reduce LBS in workplaces should focus on reducing working in awkward/tiring positions, improving contact and cooperation with management, and reducing stressful jobs, especially amongst females. PRACTITIONER SUMMARY: Strategies to prevent or reduce LBS should focus on reducing exposure to awkward or tiring positions at work, improving contact and cooperation with management, and reducing stressful jobs, especially for females.

Risk factors associated with back pain in New Zealand school children.

This study investigated risk factors associated with back pain in 245 New Zealand intermediate school children aged 11-14 years in a cross-sectional survey, using a self-completion questionnaire for demographic details, pain prevalence, psychosocial parameters, school and leisure activities and family characteristics. The strongest relationships were between back pain and common childhood complaints (stomach ache, headache and sore throats) (p < 0.01) and psychosocial factors (conduct and hyperactivity) (p < 0.01). For physical factors, there was a significant relationship between neck and low back pain and attributes of chairs. Low back pain was significantly related to low desk height (as reported by students) (p < 0.05). School bag weight was not significantly related to low back pain but carrying the bag on one shoulder was (p < 0.05). It is concluded that, amongst these intermediate school children, psychological, social and emotional factors had a stronger relationship with back pain than physical factors. STATEMENT OF RELEVANCE: This study investigated risk factors associated with back pain amongst New Zealand intermediate school children. It showed that psychological, social and emotional factors may have a stronger relationship with back pain than physical factors.

The New Zealand workforce survey I: self-reported occupational exposures.

INTRODUCTION: This study examines the prevalence of a range of occupational risk factors reported by a random sample of the New Zealand working population. METHODS: Men and women aged 20-64 were selected from the New Zealand Electoral Roll and invited to take part in a telephone interview, which collected information on lifetime work history, current workplace exposures and organizational factors, and various health conditions. The prevalences of occupational risk factors in each occupational and industry group are reported. RESULTS: Three thousand and three interviews were completed (37% of the eligible sample and 55% of those that could be contacted). Trades workers reported the highest prevalences of exposure to dust (75%) and oils and solvents (59%). Agriculture and fishery workers reported the highest prevalences of exposure to pesticides (63%) and acids or alkalis (25%). Plant and machine operators and assemblers reported the highest prevalences of exposure to smoke/fume/gas (43%), working night shift in the previous 4 weeks (18%), and working irregular hours (33%). In the high exposure occupational and industry groups, males reported a higher prevalence of exposure than females. Lifting, exposure to loud noise, and the use of personal protective equipment were reported by >50% of the manual occupational groups. CONCLUSIONS: This study indicates that occupational exposure to risk factors for work-related disease and injury remains common in the New Zealand working population. While these occupational exposures are disproportionately experienced by workers in certain industries, they also occur in occupational groups not traditionally associated with hazardous exposures or occupational disease.

The prevalence and characteristics of back pain among school children in New Zealand.

A cross-sectional survey among 245 children was conducted to establish the prevalence and characteristics of back pain in school children aged 11-14 years. A self-complete questionnaire was used to ascertain demographic details, pain prevalence, psychosocial parameters, school and leisure activities and family characteristics. In the last month, 58% of children had experienced spinal pain. In total, 31% of children reported that pain occurred in one part of the back, while 28% stated that pain presented in more than one spinal region. Pain in the last month was found to be equally prevalent in the low back (35%) and neck (36%) regions. Low back pain was associated with the most severe pain and pain lasting for the longest duration when compared with the upper back and neck regions. Further research should be directed towards investigating pain in the neck region and understanding the characteristics of symptom co-occurrence. STATEMENT OF RELEVANCE: A survey was conducted to establish the prevalence and characteristics of back pain in school children. The results provide additional evidence that back pain is a serious problem in children aged 11-14 years, whilst also indicating widespread co-occurrence of pain in the neck, upper back and lower back spinal regions.

The effects of introducing electric adjustable height desks in an office setting on workplace physical activity levels: A randomised control field trial.

BACKGROUND: Electric adjustable height desks (EAHD) have been promoted as an opportunity for desk based workers to stand at work but there is limited evidence that they have an effect on light physical activity. OBJECTIVE: The main objective was to determine if there would be a change in light physical activity with the introduction of EAHD. The secondary objective was to assess if there was an associated change in leisure time activity. METHODS: Activity levels were measured by step counts, self-reported activity levels and pre- and post-trial recall levels. Statistical analysis of the data was performed with the software R. Generalised linear models were fitted to the data. A Poisson regression was used for count data. Statistical hypotheses were deemed significant if their p values were less than 0.05. RESULTS: There was a significant (p < 0.001) effect on step counts associated with allocation of EAHD and a significant (p < 0.001) increase in self-reported activity for the Intervention (EAHD) group. Having an EAHD was associated with increased activity during leisure (p = 0.039). CONCLUSIONS: Activity levels, especially light physical activity, were significantly increased with the allocation of an electric adjustable height desk. This pilot study showed that the environmental change of introduction of electric adjustable height desks into an office workplace can increase physical activity and reduce sitting durations. There is limited evidence that the increase in work activity has a positive impact on leisure time activity.

How was a national moving and handling people guideline intended to work? The underlying programme theory.

In healthcare, moving and handling people (MHP) often cause musculoskeletal disorders. To prevent musculoskeletal disorders due to MHP, many national evidence-based guidelines have been developed. However, little is known about how these guidelines were intended to work, i.e. their 'programme theory', how implementation by intended users is influenced by contextual factors and mechanisms to produce outcomes. This paper identifies the programme theory of a national MHP guideline (MHPG) using thematic analysis of the MHPG document, three organisational planning documents, and interviews with MHPG developers. The analysis identified the intended users of the MHPG as health and safety managers and MHP coordinators. The programme theory comprised contextual factors, potentially hindering (e.g. budget constraints) or facilitating (e.g. changing demographics) implementation, being influenced by mechanisms mainly based on ethical (quality of care, evidence-based practices), and economic reasoning (reducing cost of MHP, return on investment) to reduce injuries caused by MHP - the intended outcome.

The impact of national guidelines covering moving and handling of people on injury rates and related costs.

Objective National guidelines for moving and handling of people (MHP) were introduced in New Zealand in 2012 to reduce MHP-related injuries in the healthcare sector. This study assessed the effectiveness of this on MHP-related injury claims. Methods MHP-related injury claims were identified from the national injury claims database, which included 118 755 accepted claims for 2005-2016 across 14 industries. Interrupted time-series analysis was used to assess temporal changes in MHP-related claims rates, costs, and causes for the period before (2005-2012) and following (2013-2016) the introduction of the national guidelines. Results Prior to the introduction of the guidelines, MHP-related claims were estimated to be 39 209 (33.0% of all accepted injury claims), with claims rates and associated costs for the 14 industries decreasing by 0.4 [95% confidence interval (CI) -0.5‒ -0.2, P<0.001] and NZ$ 230 per claim (95% CI -324‒ -136, P=0.001) respectively. In the year following the introduction of the guidelines, there were no overall changes in claim rates or costs. However, significant increases in claim rates [ranging from 1.27-1.99 (P=0.004-0.010)] and claim costs [ranging from NZ$ 724-987 per claim (P=0.032-0.045)] were found 2-4 years later. More than 65% of all MHP-related claims were caused by lifting/carrying/strain, and there was a significant increase in claim numbers due to this cause, ranging from 431.7-594.0 (P=0.001-0.008) in the four years following the introduction of the guidelines. Conclusions The introduction of national MHP-guidelines in 2012 in New Zealand did not reduce MHP-related injury rates and costs. On the contrary, there were statistically significant increases 2-4 years after introduction of the guidelines.

Age-dependent variability in spatiotemporal gait parameters and the walk-to-run transition.

Adolescents tend to exhibit more variability in their gait patterns than adults, suggesting a lack of gait maturity during this period of ongoing musculoskeletal growth and development. However, there is a lack of consensus over the age at which mature gait patterns are achieved and the factors contributing to gait maturation. Therefore, the purpose of this study was to investigate gait control and maturity in adolescents by determining if differences existed between adolescents and adults in a) the amount of spatiotemporal variability of walking and running patterns across a range of speeds, and b) how swiftly gait patterns are adapted to increasing gait speed during the walk-to-run transition. Forty-six adolescents (10-12-year-olds, n = 17; 13-14-year-olds, n = 12; and 15-17-year-olds, n = 17) and 12 young adults completed an incrementally ramped treadmill test (+0.2 km·h-1 every 30 s) to determine the preferred transition speed (PTS) during a walk-to-run transition. Age-related differences in the variability of stride lengths and stride durations were assessed across 4 speeds (self-selected walking speed, PTS - 0.06 m·s-1, PTS + 0.06 m·s-1, PTS + 0.83 m·s-1). Repeated measures ANOVAs (p < 0.05) compared coefficients of variation for these spatiotemporal parameters, while a one-way ANOVA compared the numbers of gait transitions and speed increments used to identify PTS between the adolescent groups and young adults. Compared to adults, 10-12yo exhibited more spatiotemporal variability during all gait conditions, while 13-17yo only exhibited more variability at PTS + 0.06 m·s-1. No age-dependent pattern was observed in PTS values, but 10-12yo completed more gait transitions over more speed increments than 15-17yo and adults. The development of mature gait patterns is thus a progressive process, with walking maturing at an earlier age than running. As 10-12yo were unable to swiftly adapt gait patterns to the changing task demands, their control mechanisms of gait may not have fully matured yet.

Ergonomics for schools.

Ergonomics in Schools has focused on micro-ergonomics issues such as mismatch between student body sizes and their desks and chairs, the weight of schoolbags and the prevalence of musculoskeletal disorders amongst school students. Very little of this has been turned into practice. Although advances in this context are being made by the International Ergonomics (IEA) Technical Committee (TC) on Ergonomics for Children in Educational Environments (ECEE), the UK Ergonomics Society Special Interest Group on Ergonomics for Schools and the New Zealand Ergonomics Society Ergonomics/Human factors in Education (EHFIE) Special Interest Group, there has been less focus on macro-ergonomics issues such as learning environments, ergonomics pedagogy and curriculum content/structure. This commentary reviews micro-ergonomics aspects of ;Ergonomics in schools' and argues in favour of a new direction: macro-ergonomics for schools, or educational ergonomics in which ergonomists seek to integrate ergonomics into national educational curricula in concert with Ministries of Education and also via inclusion of ergonomics modules in teacher training.

What factors determine the preferred gait transition speed in humans? A review of the triggering mechanisms.

Human locomotion is a fundamental skill that is required for daily living, yet it is not completely known how human gait is regulated in a manner that seems so effortless. Gait transitions have been analyzed to gain insight into the control mechanisms of human locomotion since there is a known change that occurs as the speed of locomotion changes. Specifically, as gait speed changes, there is a spontaneous transition between walking and running that occurs at a particular speed. Despite the growing body of research on the determinants of this preferred transition speed and thus the triggering mechanisms of human gait transitions, a clear consensus regarding the control mechanisms of gait is still lacking. Therefore, this article reviews the determinants of the preferred transition speed using concepts of the dynamic systems theory and how these determinants contribute to four proposed triggers (i.e. metabolic efficiency, mechanical efficiency, mechanical load and cognitive and perceptual) of human gait transitions. While individual anthropometric and strength characteristics influence the preferred transition speed, they do not act to trigger a gait transition. The research has more strongly supported the mechanical efficiency and mechanical load determinants as triggering mechanisms of human gait transitions. These mechanical determinants, combined with cognitive and perceptual processes may thus be used to regulate human gait patterns through proprioceptive and perceptual feedback as the speed of locomotion changes.

The effect of simulated school load carriage configurations on shoulder strap tension forces and shoulder interface pressure.

Recently, several studies have addressed the physical demands of school student's load carriage, in particular the load weight carried, using physical demands indicators such as oxygen consumption, gait, and posture. The objective of this study was to determine the effects of different load carriage configurations on shoulder strap tension forces and shoulder interface pressure during simulated school student's load carriage. A load carriage simulator was used to compare shoulder strap forces and shoulder pressure for 32 combinations of gait speed, backpack weight, load distribution, shoulder strap length and use of a hip-belt. The results showed that the manipulation of backpack weight, hip-belt use and shoulder strap length had a strong effect on shoulder strap tension and shoulder pressure. Backpack weight had the greatest influence on shoulder strap tension and shoulder pressure, whereas hip-belt use and then shoulder strap adjustment had the next greatest effects, respectively. While it is clear that researchers and practitioners are justified in focusing on load magnitude in backpack studies as it has the greatest effect on shoulder forces, hip-belt use and shoulder strap adjustment should also be examined further as they too may have significant effects on the demands placed on backpack users. Based on the present findings, school students should wear their backpacks with the least weight possible, use the hip-belt if present, allow a reasonable amount of looseness in the shoulder straps and should position the heaviest items closest to their back. However, more detailed work using human participants needs to be undertaken before these recommendations can be confirmed.

Interaction between physical and psychosocial work risk factors for low back symptoms and its consequences amongst Indonesian coal mining workers.

This study assessed the interaction between physical and psychosocial factors for low back symptoms (LBS) and its consequences (reduced activities and absenteeism) in a developing country. A sample of 1294 Indonesian coal mining workers reported occupational exposures, LBS and its consequences using a self-administered questionnaire. Respondents were placed into one of four combination exposure groups: high physical and high psychosocial (HPhyHPsy); high physical and low psychosocial (HPhyLPsy); low physical and high psychosocial (LPhyHPsy), and; low physical and low psychosocial (LPhyLPsy). The attributable proportion due to interaction between physical and psychosocial factors was examined. Individuals in the HPhyHPsy group were most likely to report LBS (OR 5.42, 95% CI 3.30-8.89), reduced activities (OR 4.89, 95% CI 3.09-7.74), and absenteeism (OR 4.96, 95% CI 3.05-8.06). Interactions between physical and psychosocial factors were present for LBS, reduced activities, and absenteeism; although for LBS and absenteeism the interactions were not significant. Current smokers were more likely to report LBS consequences. Permanent employment and night shift work increased the odds of LBS and its consequences. We conclude that interventions aimed at reducing LBS and its consequences should address both physical and psychosocial factors, with a focus on smokers, permanent employment and night shift work.

The effect of cell phone type on drivers subjective workload during concurrent driving and conversing.

The effect of three types of cell phones (hand held, hands free with an external speaker and personal hands free) on total subjective workload (including its constituent components; mental demand, physical demand, temporal demand, performance, effort and frustration) and intelligibility was measured using the NASA-task load index (TLX) and the modified rhyme test (MRT), respectively in 13 experienced drivers (nine male, four female, age range 28-65 years), whilst driving on a rural highway. The drivers rated all components of workload for each type of cell phone to be significantly higher than for a control condition in which no cell phone was used. The mean (standard deviation) total workload was lowest for the personal hands free cell phone (7.1(3.65)) and highest for the hands free speaker phone (10.8 (3.63)) (P<0.001). The mean (standard deviation) intelligibility score was highest for the personal hands free cell phone (74.1 (7.9)) and lowest for the hands free speaker phone (55.0 (10.4)) (P<0.001). Frustration was significantly correlated with total workload (0.60, P<0.001) and intelligibility was significantly correlated with frustration (-0.35, P<0.05). Physical demand was not a high contributor to total workload. It is concluded that a personal hands free cell phone would interfere least with the cognitive demands of driving.

Development of activity monitoring for determining load carriage patterns in school students.

The loads that school students are carrying to, around and from school is an issue of increasing concern particularly as the long term effects of excessive load carriage on school students' musculoskeletal health is unknown. A greater understanding of the temporal patterns of students' load carriage, which usually involves backpacking, would assist in determining the magnitude of the problem that is faced by school students. The aim of this study was to determine the duration of school students' walking, running and stair climbing while backpacking and identify when students take off and put on their backpacks using activity monitoring and video, and therefore validate activity monitoring as a tool for measuring the temporal patterns of backpacking in school students. An activity monitor was secured in the backpacks of six school students while they completed a predefined physical activity course. Participants firstly completed the course following a set time pattern ('set course') and then repeated the course while performing activities as they pleased ('free course'). Video footage and activity monitor data were captured simultaneously. The activity monitor provided consistent visual differentiation between walking, running and taking off and putting on a backpack. The greatest variation between measures was for walking during the 'free course' (mean 8, SD 7 seconds), while the least variation between measures was for stair climbing during the 'set course' (mean 3, SD 2 seconds). There were no statistical differences between the activity monitor and video camera determined durations for any of the activities. These preliminary results suggest that activity monitoring may enable valid analysis of the temporal patterns of backpacking with little disruption to the user, although more work is required to verify this.