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Garcia G, Arauz PG, Alvarez I, Encalada N, Vega S, Baldo M, Martin BJ. Effects of a passive upper-body exoskeleton on whole-body kinematics, leg muscle activity, and discomfort during a carrying task. PLoS One 2024; 19:e0304606. [PMID: 38990910 PMCID: PMC11238980 DOI: 10.1371/journal.pone.0304606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 05/14/2024] [Indexed: 07/13/2024] Open
Abstract
OBJECTIVE To compare whole-body kinematics, leg muscle activity, and discomfort while performing a 10-min carrying task with and without a passive upper-body exoskeleton (CarrySuitⓇ), for both males and females. BACKGROUND Diverse commercial passive exoskeletons have appeared on the market claiming to assist lifting or carrying task. However, evidence of their impact on kinematics, muscle activity, and discomfort while performing these tasks are necessary to determine their benefits and/or limitations. METHOD Sixteen females and fourteen males carried a 15kg load with and without a passive exoskeleton during 10-min over a round trip route, in two non-consecutive days. Whole-body kinematics and leg muscle activity were evaluated for each condition. In addition, leg discomfort ratings were quantified before and immediately after the task. RESULTS The gastrocnemius and vastus lateralis muscle activity remained constant over the task with the exoskeleton. Without the exoskeleton a small decrease of gastrocnemius median activation was observed regardless of sex, and a small increase in static vastus lateralis activation was observed only for females. Several differences in sagittal, frontal, and transverse movements' ranges of motion were found between conditions and over the task. With the exoskeleton, ROM in the sagittal plane increased over time for the right ankle and pelvis for both sexes, and knees for males only. Thorax ROMs in the three planes were higher for females only when using the exoskeleton. Leg discomfort was lower with the exoskeleton than without. CONCLUSION The results revealed a positive impact on range of motion, leg muscle activity, and discomfort of the tested exoskeleton.
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Affiliation(s)
- Gabriela Garcia
- Departamento de Ingeniería Industrial, Colegio de Ciencias e Ingenierías, Universidad San Francisco de Quito USFQ, Quito, Ecuador
| | - Paul Gonzalo Arauz
- Department of Orthopaedics, Renaissance School of Medicine, Stony Brook University, New York, NY, United States of America
| | - Isabel Alvarez
- Departamento de Ingeniería Industrial, Colegio de Ciencias e Ingenierías, Universidad San Francisco de Quito USFQ, Quito, Ecuador
| | - Nicolas Encalada
- Departamento de Ingeniería Industrial, Colegio de Ciencias e Ingenierías, Universidad San Francisco de Quito USFQ, Quito, Ecuador
| | - Shirley Vega
- Departamento de Ingeniería Industrial, Colegio de Ciencias e Ingenierías, Universidad San Francisco de Quito USFQ, Quito, Ecuador
| | - Marco Baldo
- Departamento de Ingeniería Industrial, Colegio de Ciencias e Ingenierías, Universidad San Francisco de Quito USFQ, Quito, Ecuador
| | - Bernard J. Martin
- Department of Industrial and Operations Engineering, University of Michigan, Ann Arbor, Michigan, United States of America
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Pitts J, Komisar V, Elmblad K, Smith A, Verbrigghe D, Siko C, Nussbaum MA, Duncan CA. Influences of backpack loading on recovery from anterior and posterior losses of balance: An exploratory investigation. APPLIED ERGONOMICS 2024; 117:104236. [PMID: 38237306 DOI: 10.1016/j.apergo.2024.104236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 12/01/2023] [Accepted: 01/09/2024] [Indexed: 02/27/2024]
Abstract
Backpacks are common devices for carrying external posterior loads. However, relatively little is known about how these external loads affect the ability to recover from balance loss. In this exploratory investigation, 16 young adults (8 female, 8 male) performed forward and backward lean-and-release balance recovery trials, while wearing a backpack that was unloaded or loaded (at 15% of individual body weight). We quantified the effects of backpack loading on balance recovery in terms of maximum recoverable lean angles, center-of-mass kinematics, and temporal-spatial stepping characteristics. Mean values of maximum lean angles were 20° and 9° in response to forward and backward perturbations, respectively. These angles significantly decreased when wearing the additional load for only backward losses of balance. During backward losses of balance, the additional load decreased peak center-of-mass velocity and increased acceleration by ∼10 and 18% respectively, which was accompanied by ∼5% faster stepping responses and steps that were ∼9% longer, 11% higher, and had an ∼10% earlier onset. Thus, wearing a backpack decreases backward balance recovery ability and changes backward recovery stepping characteristics.
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Affiliation(s)
- Jessica Pitts
- Department of Kinesiology and Integrative Physiology, Student Development Complex, 1400 Townsend Drive, Michigan Technological University, Houghton, MI, 49922, USA.
| | - Vicki Komisar
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, 8888 University Drive, Burnaby, BC, V5A 1S6, Canada
| | - Kayley Elmblad
- Department of Mechanical Engineering and Engineering Mechanics, R. L. Smith ME-EM Building, 8th Floor, 1400 Townsend Drive, Houghton, MI, 49931, USA
| | - Alyssa Smith
- Department of Kinesiology and Integrative Physiology, Student Development Complex, 1400 Townsend Drive, Michigan Technological University, Houghton, MI, 49922, USA
| | - Derek Verbrigghe
- Department of Physical Therapy, Central Michigan University, 1200S Franklin St, Mount Pleasant, MI, 48859, USA
| | - Carly Siko
- Department of Physical Therapy, Central Michigan University, 1200S Franklin St, Mount Pleasant, MI, 48859, USA
| | - Maury A Nussbaum
- Department of Industrial and Systems Engineering, 521 Whittemore Hall, 1185 Perry Street (0118), Blacksburg, VA, 24061, USA
| | - Carolyn A Duncan
- Department of Kinesiology and Integrative Physiology, Student Development Complex, 1400 Townsend Drive, Michigan Technological University, Houghton, MI, 49922, USA.
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Hoolihan B, Wheat J, Dascombe B, Vickery-Howe D, Middleton K. The effect of external loads and biological sex on coupling variability during load carriage. Gait Posture 2023; 100:236-242. [PMID: 36640597 DOI: 10.1016/j.gaitpost.2023.01.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 10/27/2022] [Accepted: 01/08/2023] [Indexed: 01/11/2023]
Abstract
BACKGROUND Load carriage is a fundamental requirement for military personnel that commonly results in lower-limb injuries. Coupling variability represents a potential injury mechanism for such repetitive tasks and its unknown whether external loads and biological sex affect coupling variability during load carriage. RESEARCH QUESTION Is there a sex-by-load interaction during load carriage at self-selected walking speeds? METHODS Twenty-six participants (13 males, 13 females) completed three 10-minute treadmill-based trials wearing body-borne external load (0 %BM, 20 %BM, and 40 %BM) at load-specific self-selected walking speeds. A Vicon motion capture system tracked markers with a lower-body direct-kinematic model calculating sagittal-plane segment kinematics of the thigh, shank, and foot across 19 strides. Continuous relative phase standard deviation (CRPv) provided a measure of coupling variability for each coupling angle (Thigh-Shank and Shank-Foot). The CRPv for each load and sex was compared using statistical parametric mapping repeated measures ANOVA and paired t tests. RESULTS Significant sex-by-load interactions were reported for the Thigh-Shank coupling. Males demonstrated no significant load differences in CRPv, however, females displayed significantly higher CRPv in the 40 %BM than the 0 %BM condition. A significant main effect of load was observed in the Shank-Foot coupling, with the 40 %BM having significantly greater CRPv than the other load conditions. SIGNIFICANCE Both biological sex and external loads significantly affected CRPv during load carriage at self-selected walking speeds. Females demonstrated greater CRPv at the heavier loads, suggesting that the perturbation from the heavier mass increases coupling variability, which may also be amplified by a greater total passive load due to their relatively higher adipose tissue compared to males. The consistent CRPv in males suggests that higher relative loads may be required to change coupling variability. Collectively, these results suggest that external load affects the coupling variability of males and females differently, providing potential for injury screening and monitoring programs.
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Affiliation(s)
- Brooke Hoolihan
- Applied Sport Science and Exercise Testing Laboratory, School of Environmental and Life Sciences, University of Newcastle, Ourimbah, Australia; Applied Biomechanics Laboratory, School of Allied Health, Human Services and Sport, La Trobe University, Bundoora, Australia.
| | - Jonathan Wheat
- Sports Engineering Research Group, Sport and Physical Activity Research Centre, Sheffield Hallam University, Sheffield, UK
| | - Ben Dascombe
- Applied Sport Science and Exercise Testing Laboratory, School of Environmental and Life Sciences, University of Newcastle, Ourimbah, Australia
| | - Danielle Vickery-Howe
- Applied Biomechanics Laboratory, School of Allied Health, Human Services and Sport, La Trobe University, Bundoora, Australia; Sport, Performance, and Nutrition Research Group, School of Allied Health, Human Services and Sport, La Trobe University, Bundoora, Australia
| | - Kane Middleton
- Applied Biomechanics Laboratory, School of Allied Health, Human Services and Sport, La Trobe University, Bundoora, Australia; Sport, Performance, and Nutrition Research Group, School of Allied Health, Human Services and Sport, La Trobe University, Bundoora, Australia
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Impact of Backpacks on Ergonomics: Biomechanical and Physiological Effects: A Narrative Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19116737. [PMID: 35682317 PMCID: PMC9180465 DOI: 10.3390/ijerph19116737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 05/20/2022] [Accepted: 05/25/2022] [Indexed: 11/24/2022]
Abstract
(1) Background: the effects of load carriage packs on human gait biomechanics, physiology and metabolism depend on the weight carried, the design of the pack and its interaction with the user. (2) Methods: An extensive search in the PubMed database was performed to find all the relevant articles using the following keywords: backpack, rucksack, backpack ergonomy and sports backpack; 60 articles were included. (3) Results and significance: Double pack (DP) and T-pack (TP) designs are recommended solutions for school children, compared with backpacks (BP). For soldiers and hikers, a backpack remains the best compromise. A hip belt is recommended for BPs as well as for the back of DPs. Shorter and stiffer shoulder straps combined with a higher and tighter load placement on the back provide the best combination in terms of balance, muscle activation and energy expenditure. It is, therefore, possible to determine guidelines for designing the optimal load carriage system, depending on the application. (4) Conclusions: based on the available evidence, DP and TP are advantageous in terms of posture. DP is better than conventional BPs in terms of balance and muscle activation, but has the disadvantage of limited visibility, thermal sensation and obstructed ventilation. In general, it is desirable not to exceed 40% of body mass (BM).
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Doran M, Öneş K, Terzibaşioğlu AM, Ҫinar Ҫ, Ata İ. Ultrasonographic evaluation of abdominal muscle thickness symmetry in adolescent idiopathic scoliosis: a case controlled study. Eur J Phys Rehabil Med 2021; 57:968-976. [PMID: 34196160 DOI: 10.23736/s1973-9087.21.06833-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND To date, there are limited studies evaluating abdominal muscle symmetry in adolescent idiopathic scoliosis (AIS) patients and these studies in the literature do not evaluate the rectus abdominis (RA) muscle in AIS patients. AIM To evaluate the symmetry of the thickness of the abdominal muscles while standing and supine position in AIS patients. DESİGN: A case control study. METHODS AND POPULATION Radiographic examination data of patients with AIS (n=40) were collected. An ultrasound assessment was performed of the side-to-side differences of the RA, external oblique (EO), internal oblique (IO), and transversus abdominalis (TrA) muscles in the standing and supine positions in AIS and control groups (n=40). Three repeat measurements of the thickness of each muscle were performed and relative thicknesses were compared. RESULTS The mean percentage (%) difference between the right and left sides muscle measurement of the control group was between on standing position 1.54% and 3.00%, in supine 0.8% and 5.87% for different muscles; however, the meanpercentage (%) of this difference in the ASI group ranged from 6.28% to 15.13% (standing ) and 7.21% to 17.24% (supine). Muscle asymmetry in the ASI group was significantly higher than in the control group for all muscles in measurements in the standing and supine position (p <0.001). CONCLUSIONS All abdominal relative muscle thicknesses in the AİS patients were more asymmetric than healthy adolacents.
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Affiliation(s)
- Muhsin Doran
- Department of Physical Medicine and Rehabilitation, Istanbul Physical Medicine and Rehabilitation Training and Research Hospital, Health Sciences University, Istanbul, Turkey -
| | - Kadriye Öneş
- Department of Physical Medicine and Rehabilitation, Istanbul Physical Medicine and Rehabilitation Training and Research Hospital, Health Sciences University, Istanbul, Turkey
| | - Aynur M Terzibaşioğlu
- Department of Physical Medicine and Rehabilitation, Istanbul Physical Medicine and Rehabilitation Training and Research Hospital, Health Sciences University, Istanbul, Turkey
| | - Ҫiğdem Ҫinar
- Department of Physical Medicine and Rehabilitation, Istanbul Physical Medicine and Rehabilitation Training and Research Hospital, Health Sciences University, Istanbul, Turkey
| | - İlhami Ata
- Department of Physical Medicine and Rehabilitation, Istanbul Physical Medicine and Rehabilitation Training and Research Hospital, Health Sciences University, Istanbul, Turkey
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Liew BXW, Morris S, Netto K. Trunk-pelvis coordination during load carriage running. J Biomech 2020; 109:109949. [PMID: 32807302 DOI: 10.1016/j.jbiomech.2020.109949] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 07/06/2020] [Accepted: 07/08/2020] [Indexed: 10/23/2022]
Abstract
Understanding the influence of load carriage on trunk-pelvis coordination and its variability has important functional implications for athletes who need to run with load. The aim of this study was to examine the influence of load carriage on trunk-pelvis coordination in running. Thirty healthy adults performed running while wearing a 20% bodyweight backpack, and without load. Vector coding was used to quantify trunk-pelvis segmental coordination and its variability during the stance phase of running. The four coordination patterns were: 1) anti-phase (segments moving in opposite directions), in-phase (segments moving in same directions), trunk-only phase (only trunk movement), and pelvic-only phase (only pelvic movement). For each plane, the percentage of stance phase spent in a specific coordination pattern was quantified. Coordination variability for each plane was averaged over the stance phase. Mixed effects models were used to analyse the effects of load, adjusted for the covariate of sex, on coordination and its variability. Running with load increased trunk-only coordination in the sagittal plane (P < 0.001), increased anti-phase coordination in the frontal plane (P < 0.001), reduced trunk-only phase coordination in axial rotation (P < 0.001), and increased coordination variability in all three planes (Flexion-Extension: P < 0.001; Lateral flexion: P = 0.03; Axial rotation: P < 0.001). Future studies would benefit from investigating how trunk-pelvis coordination and its variability alters candidate end-point variability indices (e.g. COM displacement), and its functional implications in load carriage running.
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Affiliation(s)
- Bernard X W Liew
- School of Sport, Rehabilitation and Exercise Sciences, University of Essex, Colchester, Essex CO4 3SQ, United Kingdom.
| | - Susan Morris
- School of Physiotherapy and Exercise Sciences, Curtin University, GPO Box U1987, Perth, WA 6845, Australia
| | - Kevin Netto
- School of Physiotherapy and Exercise Sciences, Curtin University, GPO Box U1987, Perth, WA 6845, Australia
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Sessoms PH, Gobrecht M, Niederberger BA, Sturdy JT, Collins JD, Dominguez JA, Jaworski RL, Kelly KR. Effect of a load distribution system on mobility and performance during simulated and field hiking while under load. ERGONOMICS 2020; 63:133-144. [PMID: 31709928 DOI: 10.1080/00140139.2019.1690710] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Accepted: 10/31/2019] [Indexed: 06/10/2023]
Abstract
This study was conducted to test a modular scalable vest-load distribution system (MSV-LDS) against the plate carrier system (PC) currently used by the United States Marine Corps. Ten Marines engaged in 1.6 km load carriage trials in seven experimental conditions in a laboratory study. Kinematic, kinetic, and spatiotemporal gait parameters, muscle activity (electromyography), heart rate, caloric expenditure, shooting reaction times, and subjective responses were recorded. There was lower mean trapezius recruitment for the PC compared with the MSV-LDS for all conditions, and muscle activity was similar to baseline for the MSV-LDS. Twenty-seven Marines carrying the highest load were evaluated in the field, which measured an increase in energy expenditure with MSV-LDS; however, back discomfort was reduced. The field evaluation showed significantly reduced estimated ground reaction force on flat-ground segments with the MSV-LDS, and the data suggest both systems were comparable with respect to mobility and energy cost. Practitioner summary: This study found that a novel load distribution system appears to redistribute load for improved comfort as well as reduce estimated ground reaction force when engaged in hiking activities. Further, hiking with a load distribution system enables more neutral walking posture. Implications of load differences in loads carried are examined. Abbreviations: AGRF: anterior-posterior ground reaction forces; CAREN: Computer Assisted Rehabilitation Environment; GRF: ground reaction forces; HR: heart rate; ML-GRF: mediolateral ground reaction forces; MOLLE: Modular Lightweight Load-carrying Equipment; MSV-LDS: modular scalable vest-load distribution system; NHRC: Naval Health Research Center; PC: plate carrier; PPE: personal protective equipment; RPE: rating of perceived exertion; SAPI: small arms protective insert; sEMG: surface electromyography; USMC: United States Marine Corps; VGRF: Ground reaction forces in the vertical.
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Affiliation(s)
- Pinata H Sessoms
- Warfighter Performance Department, Naval Health Research Center, San Diego, CA, USA
- School of Exercise and Nutritional Sciences, San Diego State University, San Diego, CA, USA
| | - Marcus Gobrecht
- School of Exercise and Nutritional Sciences, San Diego State University, San Diego, CA, USA
| | | | | | | | - Jose A Dominguez
- Warfighter Performance Department, Naval Health Research Center, San Diego, CA, USA
| | - Rebecca L Jaworski
- Warfighter Performance Department, Naval Health Research Center, San Diego, CA, USA
| | - Karen R Kelly
- Warfighter Performance Department, Naval Health Research Center, San Diego, CA, USA
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Lenton GK, Saxby DJ, Lloyd DG, Billing D, Higgs J, Doyle TL. Primarily hip-borne load carriage does not alter biomechanical risk factors for overuse injuries in soldiers. J Sci Med Sport 2019; 22:158-163. [DOI: 10.1016/j.jsams.2018.06.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 05/28/2018] [Accepted: 06/21/2018] [Indexed: 10/28/2022]
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Lenton GK, Bishop PJ, Saxby DJ, Doyle TLA, Pizzolato C, Billing D, Lloyd DG. Tibiofemoral joint contact forces increase with load magnitude and walking speed but remain almost unchanged with different types of carried load. PLoS One 2018; 13:e0206859. [PMID: 30395591 PMCID: PMC6218072 DOI: 10.1371/journal.pone.0206859] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 10/19/2018] [Indexed: 11/25/2022] Open
Abstract
Musculoskeletal injuries (MSI) in the military reduce soldier capability and impose substantial costs. Characterizing biomechanical surrogates of MSI during commonly performed military tasks (e.g., load carriage) is necessary for evaluating the effectiveness of possible interventions to reduce MSI risk. This study determined the effects of body-borne load distribution, load magnitude, and walking speed on tibiofemoral contact forces. Twenty-one Australian Army Reserve soldiers completed a treadmill walking protocol in an unloaded condition and wearing four armor types (standard-issue and three prototypes) with two load configurations (15 and 30 kg) for a total of 8 armor x load ensembles. In each ensemble, participants completed a 5-minute warm-up, and then walked for 10 minutes at both moderate (1.53 m⋅s-1) and fast (1.81 m⋅s-1) speeds. During treadmill walking, three-dimensional kinematics, ground reaction forces, and muscle activity from nine lower-limb muscles were collected in the final minute of each speed. These data were used as inputs into a neuromusculoskeletal model, which estimated medial, lateral and total tibiofemoral contact forces. Repeated measures analyses of variance revealed no differences for any variables between armor types, but peak medial compartment contact forces increased when progressing from moderate to fast walking and with increased load (p<0.001). Acute exposure to load carriage increased estimated tibiofemoral contact forces 10.1 and 19.9% with 15 and 30kg of carried load, respectively, compared to unloaded walking. These results suggest that soldiers carrying loads in excess of 15 kg for prolonged periods could be at greater risk of knee MSI than those with less exposure.
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Affiliation(s)
- Gavin K. Lenton
- Gold Coast Orthopaedics Research, Engineering and Education Alliance, Menzies Health Institute Queensland, School of Allied Health Sciences, Griffith University, Southport, Queensland, Australia
- * E-mail:
| | - Peter J. Bishop
- Gold Coast Orthopaedics Research, Engineering and Education Alliance, Menzies Health Institute Queensland, School of Allied Health Sciences, Griffith University, Southport, Queensland, Australia
| | - David J. Saxby
- Gold Coast Orthopaedics Research, Engineering and Education Alliance, Menzies Health Institute Queensland, School of Allied Health Sciences, Griffith University, Southport, Queensland, Australia
| | - Tim L. A. Doyle
- Department of Health Professions, Faculty of Medicine and Health Sciences, Macquarie University, New South Wales, Australia
| | - Claudio Pizzolato
- Gold Coast Orthopaedics Research, Engineering and Education Alliance, Menzies Health Institute Queensland, School of Allied Health Sciences, Griffith University, Southport, Queensland, Australia
| | - Daniel Billing
- Land Division, Defence Science and Technology Group, Fishermans Bend, VIC, Australia
| | - David G. Lloyd
- Gold Coast Orthopaedics Research, Engineering and Education Alliance, Menzies Health Institute Queensland, School of Allied Health Sciences, Griffith University, Southport, Queensland, Australia
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The Influence of Backpack Weight and Hip Belt Tension on Movement and Loading in the Pelvis and Lower Limbs during Walking. Appl Bionics Biomech 2018; 2018:4671956. [PMID: 29977333 PMCID: PMC6011123 DOI: 10.1155/2018/4671956] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 05/15/2018] [Indexed: 11/18/2022] Open
Abstract
The introduction of hip belts to backpacks has caused a shift of loading from the spine to the hips with reported improvements in musculoskeletal comfort. Yet the effects of different hip belt tensions on gait biomechanics remain largely unknown. The goal of this study was to assess the influence of backpack weight and hip belt tension on gait biomechanics. Data from optical motion capture and ground reaction forces (GRF) during walking were acquired in nine healthy male subjects (age 28.0 ± 3.9 years). Six configurations of a commercial backpack were analyzed, that is, 15 kg, 20 kg, and 25 kg loading with 30 N and 120 N hip belt tension. Joint ranges of motion (ROM), peak GRF, and joint moments during gait were analyzed for significant differences by repeated measures of ANOVA with Bonferroni post hoc comparison. Increased loading led to a significant reduction of knee flexion-extension ROM as well as pelvis rotational ROM. No statistically significant effect of hip belt tension magnitudes on gait dynamics was found at any backpack weight, yet there was a trend of increased pelvis ROM in the transverse plane with higher hip belt tension at 25 kg loading. Further research is needed to elucidate the optimum hip belt tension magnitudes for different loading weights to reduce the risks of injury especially with higher loading.
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Dockrell S, Jacobs K, Byrne J, Gleeson E, Kelly S, Moore C, O'Meara E, Barclay D, Rodriguez S, Kang D, Simms C, Blake C. Parental awareness of schoolbag carriage: A comparative study of Irish and United States parents. Work 2017; 58:85-93. [PMID: 28922183 DOI: 10.3233/wor-172605] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Given the global nature of schoolbag carriage, there has been extensive research on schoolbag weight and use with resultant guidance on many aspects of carrying a schoolbag. However, there is limited evidence of knowledge translation or parents' awareness of schoolbag carriage. OBJECTIVE This study investigated parental awareness of factors related to schoolbag carriage. METHOD A cross-sectional survey using an anonymous 30-item questionnaire and purposive sampling was used. Questionnaires were distributed to parents of primary school children through the schools. Descriptive statistics of frequencies and percentages were used and associations were tested using Chi-square analysis in SPSS v23. RESULTS A total of 700 parents in Ireland (Ire) and the United States (US) participated in the study (n = 444 [Ire] and n = 256 [US]). Generally, parents had satisfactory awareness of appropriate schoolbag type and carriage. The majority of children owned a backpack (89.9% [Ire] vs. 93.7% [US]), although fewer parents considered this to be the most suitable bag for their child (69.6% [Ire] vs. 88.2% [US]). More Irish parents (29.2%) favoured a wheeled schoolbag compared to US parents (6.2%) (p < 0.001). The majority (70.8% [Ire] vs. 55.7% [US]) wanted more information. The preferred platforms for receiving information were a handout (78.1% [Ire] vs. 71.6% [US]) and on-line (44.6% [Ire] vs. 53.9% [US]). CONCLUSIONS Despite gaps identified, parents had good awareness of factors relating to schoolbag carriage, but this study shows that they would like more information. The preferred platform for knowledge translation was a handout. Parents are the best advocates for safety promotion and represent the group most likely to improve schoolbag carriage among children.
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Affiliation(s)
- Sara Dockrell
- Discipline of Physiotherapy, School of Medicine, Trinity College, Dublin, Ireland
| | - Karen Jacobs
- Department of Occupational Therapy, Boston College of Health & Rehabilitation Sciences: Sargent College, Boston University, Boston, MA, USA
| | - Julie Byrne
- Discipline of Physiotherapy, School of Medicine, Trinity College, Dublin, Ireland
| | - Emma Gleeson
- Discipline of Physiotherapy, School of Medicine, Trinity College, Dublin, Ireland
| | - Sinead Kelly
- Discipline of Physiotherapy, School of Medicine, Trinity College, Dublin, Ireland
| | - Caitriona Moore
- Discipline of Physiotherapy, School of Medicine, Trinity College, Dublin, Ireland
| | - Eimear O'Meara
- Discipline of Physiotherapy, School of Medicine, Trinity College, Dublin, Ireland
| | - Dagny Barclay
- Department of Occupational Therapy, Boston College of Health & Rehabilitation Sciences: Sargent College, Boston University, Boston, MA, USA
| | - Sabrina Rodriguez
- Department of Occupational Therapy, Boston College of Health & Rehabilitation Sciences: Sargent College, Boston University, Boston, MA, USA
| | - David Kang
- Department of Occupational Therapy, Boston College of Health & Rehabilitation Sciences: Sargent College, Boston University, Boston, MA, USA
| | - Ciaran Simms
- Mechanical and Manufacturing Engineering, Trinity College, Dublin, Ireland
| | - Catherine Blake
- School of Public Health, Physiotherapy and Sports Science, Health Sciences Centre, University College Dublin, Belfield, Dublin, Ireland
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Side differences of the lateral abdominal wall in supine rest position in mild adolescent idiopathic thoracolumbar scoliosis. Turk J Phys Med Rehabil 2017; 63:224-229. [PMID: 31453458 DOI: 10.5606/tftrd.2017.333] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 08/05/2016] [Indexed: 02/05/2023] Open
Abstract
Objectives This study aims to evaluate the thickness of the abdominal muscles on both sides in patients with mild adolescent idiopathic scoliosis (AIS) and to assess the absolute and relative thickness of oblique external (OE), oblique internal (OI), and transversus abdominis (TrA). Patients and methods A total of 84 participants underwent ultrasonographic examination of the abdominal muscles in the supine resting position. All participants were divided into two groups including AIS group (n=42) and control group (n=42). The absolute and relative thicknesses of OE, OI, and TrA were recorded. Results In the AIS group, the TrA on the left side was significantly thicker by 0.30 mm (95% CI 0.01-0.7) than the right side. For relative values, the percentage contribution to the structure of the lateral abdominal wall of the OE on the right and the TrA on the left was significantly higher by 3.2% (95% CI 0.9-5.5) and 3.1% (95% CI 1.1-5.0), respectively, in the AIS group. Conclusion Our study results show that, in the supine resting position, the muscles of the lateral abdominal wall are thinner in AIS patients. In addition, side-to-side differences in the percentage contribution of the OE and TrA to the structure of the lateral abdominal wall are seen in this patient population, although these differences are independent of the direction of the scoliosis.
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Wettenschwiler PD, Annaheim S, Lorenzetti S, Ferguson SJ, Stämpfli R, Psikuta A, Rossi RM. Validation of an instrumented dummy to assess mechanical aspects of discomfort during load carriage. PLoS One 2017; 12:e0180069. [PMID: 28662084 PMCID: PMC5491328 DOI: 10.1371/journal.pone.0180069] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Accepted: 06/09/2017] [Indexed: 12/05/2022] Open
Abstract
Due to the increasing load in backpacks and other load carriage systems over the last decades, load carriage system designs have to be adapted accordingly to minimize discomfort and to reduce the risk of injury. As subject studies are labor-intensive and include further challenges such as intra-subject and inter-subject variability, we aimed to validate an instrumented dummy as an objective laboratory tool to assess the mechanical aspects of discomfort. The validation of the instrumented dummy was conducted by comparison with a recent subject study. The mechanical parameters that characterize the static and dynamic interaction between backpack and body during different backpack settings were compared. The second aim was to investigate whether high predictive power (coefficient of determination R2>0.5) in assessing the discomfort of load carriage systems could be reached using the instrumented dummy. Measurements were conducted under static conditions, simulating upright standing, and dynamic conditions, simulating level walking. Twelve different configurations of a typical load carriage system, a commercially available backpack with a hip belt, were assessed. The mechanical parameters were measured in the shoulder and the hip region of the dummy and consisted of average pressure, peak pressure, strap force and relative motion between the system and the body. The twelve configurations consisted of three different weights (15kg, 20kg, and 25kg), combined with four different hip belt tensions (30N, 60N, 90N, and 120N). Through the significant (p<0.05) correlation of the mechanical parameters measured on the dummy with the corresponding values of the subject study, the dummy was validated for all static measurements and for dynamic measurements in the hip region to accurately simulate the interaction between the human body and the load carriage system. Multiple linear regressions with the mechanical parameters measured on the dummy as independent variables and the corresponding subjective discomfort scores from the subject study as the dependent variable revealed a high predictive power of the instrumented dummy. The dummy can explain 75% or more of the variance in discomfort using average pressures as predictors and even 79% or more of the variance in discomfort using strap forces as predictors. Use of the dummy enables objective, fast, and iterative assessments of load carriage systems and therefore reduces the need for labor-intensive subject studies in order to decrease the mechanical aspects of discomfort during load carriage.
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Affiliation(s)
- Patrick D Wettenschwiler
- Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland.,Institute for Biomechanics, ETH Zurich, Zurich, Switzerland
| | - Simon Annaheim
- Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland
| | | | | | - Rolf Stämpfli
- Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland
| | - Agnes Psikuta
- Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland
| | - René M Rossi
- Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland
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Rosa RGD, Gomeñuka NA, Oliveira HBD, Peyré-Tartaruga LA. Inclined Weight-Loaded Walking at Different Speeds: Pelvis-Shoulder Coordination, Trunk Movements and Cost of Transport. J Mot Behav 2017; 50:73-79. [PMID: 28350234 DOI: 10.1080/00222895.2017.1283292] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Although studied at level surface, the trunk kinematics and pelvis-shoulder coordination of incline walking are unknown. The aim of this study was to evaluate the speed effects on pelvis-shoulder coordination and trunk movement and the cost of transport (C) during unloaded and loaded (25% of body mass) 15% incline walking. We collected 3-dimensional kinematic and oxygen consumption data from 10 physically active young men. The movements were analyzed in the sagittal plane (inclination and range of trunk motion) and the transverse plane (range of shoulder and pelvic girdle motion and phase difference). The rotational amplitude of the shoulder girdle decreased with load at all speeds, and it was lower at the highest speeds. The rotational amplitude of the pelvic girdle did not change with the different speeds. The phase difference was greater at optimal speed (3 km.hr-1, at the lowest C) in the loaded and the unloaded conditions. The trunk inclination was greater with load and increased with speed, whereas the range of trunk motion was lower in the loaded condition and decreased with increasing speed. In conclusion, the load decreased the range of girdles and trunk motion, and the pelvis-shoulder coordination seemed to be critical for the incline walking performance.
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Affiliation(s)
- Rodrigo Gomes da Rosa
- a Exercise Research Laboratory , Escola de Educação Física, Fisioterapia e Dança, Universidade Federal do Rio Grande do Sul , Porto Alegre , Brazil
| | - Natalia Andrea Gomeñuka
- a Exercise Research Laboratory , Escola de Educação Física, Fisioterapia e Dança, Universidade Federal do Rio Grande do Sul , Porto Alegre , Brazil
| | - Henrique Bianchi de Oliveira
- a Exercise Research Laboratory , Escola de Educação Física, Fisioterapia e Dança, Universidade Federal do Rio Grande do Sul , Porto Alegre , Brazil
| | - Leonardo Alexandre Peyré-Tartaruga
- a Exercise Research Laboratory , Escola de Educação Física, Fisioterapia e Dança, Universidade Federal do Rio Grande do Sul , Porto Alegre , Brazil
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Mechanical Predictors of Discomfort during Load Carriage. PLoS One 2015; 10:e0142004. [PMID: 26529414 PMCID: PMC4631336 DOI: 10.1371/journal.pone.0142004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 10/15/2015] [Indexed: 11/28/2022] Open
Abstract
Discomfort during load carriage is a major issue for activities using backpacks (e.g. infantry maneuvers, children carrying school supplies, or outdoor sports). It is currently unclear which mechanical parameters are responsible for subjectively perceived discomfort. The aim of this study was to identify objectively measured mechanical predictors of discomfort during load carriage. We compared twelve different configurations of a typical load carriage system, a commercially available backpack with a hip belt. The pressure distribution under the hip belt and the shoulder strap, as well as the tensile force in the strap and the relative motion of the backpack were measured. Multiple linear regression analyses were conducted to investigate possible predictors of discomfort. The results demonstrate that static peak pressure, or alternatively, static strap force is a significant (p<0.001) predictor of discomfort during load carriage in the shoulder and hip region, accounting for 85% or more of the variation in discomfort. As an additional finding, we discovered that the regression coefficients of these predictors are significantly smaller for the hip than for the shoulder region. As static peak pressure is measured directly on the body, it is less dependent on the type of load carriage system than static strap force. Therefore, static peak pressure is well suited as a generally applicable, objective mechanical parameter for the optimization of load carriage system design. Alternatively, when limited to load carriage systems of the type backpack with hip belt, static strap force is the most valuable predictor of discomfort. The regionally differing regression coefficients of both predictors imply that the hip region is significantly more tolerant than the shoulder region. In order to minimize discomfort, users should be encouraged to shift load from the shoulders to the hip region wherever possible, at the same time likely decreasing the risk of low back pain or injury.
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Seay JF. Biomechanics of Load Carriage. STUDIES IN MECHANOBIOLOGY, TISSUE ENGINEERING AND BIOMATERIALS 2015. [DOI: 10.1007/8415_2015_185] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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Golriz S, Hebert JJ, Foreman KB, Walker BF. The effect of hip belt use and load placement in a backpack on postural stability and perceived exertion: a within-subjects trial. ERGONOMICS 2014; 58:140-147. [PMID: 25265931 DOI: 10.1080/00140139.2014.960010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The purpose of this study was to assess the effects of hip belt use and load placement in a backpack on perceived exertion and postural stability. Thirty participants were instructed to stand on a force plate and walk along a designated route under five conditions: unloaded, high-load placement, low-load placement, hip belt on and hip belt off. The average velocity and sway area from the force plate were measured. Participants also rated their perceived stability and exertion. Compared to the unloaded condition, all loaded conditions significantly increased average velocity, sway area, perceived stability and exertion. Hip belt use did not affect average velocity and sway area; however, participants reported higher levels of stability and lower levels of exertion with hip belt use. Load placement did not affect average velocity, sway area, perceived stability or exertion. This study showed that wearing a backpack loaded to 20% of body weight reduced postural stability, while manipulation of load placement in a backpack did not affect subjective and objective measures of postural stability. Also, hip belt use only improved subjective measures of postural stability.
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Affiliation(s)
- Samira Golriz
- a School of Health Professions , Murdoch University , Perth , Australia
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Smallman CL, Graham RB, Stevenson JM. The effect of an on-body assistive device on transverse plane trunk coordination during a load carriage task. J Biomech 2013; 46:2688-94. [PMID: 24001927 DOI: 10.1016/j.jbiomech.2013.07.034] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Revised: 07/25/2013] [Accepted: 07/26/2013] [Indexed: 11/24/2022]
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Kim Y, Shim JK, Son J, Pyeon HY, Yoon B. A neuromuscular strategy to prevent spinal torsion: backward perturbation alters asymmetry of transversus abdominis muscle thickness into symmetry. Gait Posture 2013; 38:231-5. [PMID: 23266250 DOI: 10.1016/j.gaitpost.2012.11.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Revised: 10/25/2012] [Accepted: 11/14/2012] [Indexed: 02/02/2023]
Abstract
Symmetric co-contraction of the transversus abdominis (TrA) muscle is beneficial in terms of increasing trunk stability. The aim of this study was to investigate the symmetry of lateral abdominal muscle thickness during static and dynamic conditions. Fifteen male subjects (27.13 ± 5.51 years old) were instructed to sit on a chair and maintain upright posture. Every individual subject wore a jacket harness that could be backwardly attached to a 9-kg weight through a pulley system. An unexpected drop of the weight induced the transition from static to dynamic condition. The thickness of external oblique, internal oblique, and TrA muscles was measured with ultrasonography. Our results revealed more symmetry of TrA thickness during the dynamic condition (21% vs. 13%, p = 0.019) compared with the static. The symmetric muscle thickness of TrA during the dynamic condition is considered a result of more contraction on the non-dominant side. This phenomenon could be a possible strategy of deep abdominal muscles to prevent spinal torsion during sudden trunk perturbation.
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Affiliation(s)
- Yushin Kim
- Department of Physical Therapy, College of Health Sciences, Korea University, Seoul, Republic of Korea
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Interaction Between Thorax, Lumbar, and Pelvis Movements in the Transverse Plane During Gait at Three Velocities. J Appl Biomech 2013; 29:261-9. [DOI: 10.1123/jab.29.3.261] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We determined the angular range of motion and the relative timing of displacement in the thorax, lumbar spine, and pelvis in the transverse plane during treadmill walking at three velocities. Nine healthy young females walked on a treadmill for three minutes at 0.40, 0.93, and 1.47 m/s. The position of seven reflective markers and three rigs placed on the thorax, lumbar spine, and pelvis were recorded at 200 Hz by an eight-camera motion capture system. As gait velocity increased, stride length increased, cycle time decreased, and angular displacement in the thorax and L1 decreased but increased at the pelvis and L5 (allP< .05). The time of maximal angular rotation occurred in the following sequence: pelvis, L5, L3, L1, and thorax (P< .001). The thorax and L1 and L3 were in-phase for shorter duration as gait velocity increased, and this reduction was especially large, approx. 32% (P< .05), between thorax and pelvis. As gait velocity increased, the pelvis rotated earlier, causing the shortening of in-phase duration between thorax and pelvis. These data suggest that, as gait velocity increases, pelvis rotation dictates trunk rotation in the transverse plane during gait in healthy young females.
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Factors affecting shoulder-pelvic integration during axial trunk rotation in subjects with recurrent low back pain. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2012; 21:1316-23. [PMID: 22456800 DOI: 10.1007/s00586-012-2280-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Revised: 01/05/2012] [Accepted: 03/14/2012] [Indexed: 11/26/2022]
Abstract
INTRODUCTION Shoulder-pelvic integration could play a central role in the control of dynamic posture and movement. However, kinematic coordination during axial trunk rotation has not been carefully investigated in subjects with recurrent low back pain (LBP). The purpose of this study was to compare the maximum rotational angles of the shoulders and pelvis in the transverse plane between subjects with and without recurrent LBP. MATERIALS AND METHODS A total of 38 age-matched subjects (19 control subjects: 69.00 ± 5.75 years old and 19 subjects with LBP: 68.79 ± 5.40 years old) participated in the study. The axial trunk rotation test was conducted in the upright position with bilateral hips and knees fully extended and both feet shoulder width apart. RESULTS The results of this study indicated that there was a difference in pelvic girdle rotation between groups (100.79 ± 26.46 in the control group, 82.12 ± 23.16 in the LBP group; t = 2.31, p = 0.02); however, there was no difference for the shoulder girdle (177.63 ± 36.98 in the control group, 156.42 ± 30.09 in the LBP group; t = 1.91, p = 0.06). There were interactions with age (F = 9.27, p = 0.004) and BMI (F = 7.50, p = 0.01) with the rotational angles of the shoulder and pelvis. CONCLUSION These results indicated a different pattern of trunk rotation movement with the age and BMI serving as important factors to consider for recurrent LBP. The results of our study also indicated a different pattern of shoulder and pelvic coordination with age and gender. Clinicians need to consider the consequences of limited shoulder-pelvic rotational angles, especially limited rotational angle on the pelvis during trunk axial rotation. Further studies are required to determine the causes of the underlying problems for clinical decision-making and altered shoulder-pelvic rotation in subjects with recurrent LBP.
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Lloyd R, Parr B, Davies S, Cooke C. A kinetic comparison of back-loading and head-loading in Xhosa women. ERGONOMICS 2011; 54:380-391. [PMID: 21491280 DOI: 10.1080/00140139.2011.558636] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The purpose of this study was to compare the kinetic responses associated with ground reaction force measurements to both head-loading and back-loading in a group of Xhosa women. Altogether, 16 women were divided into two groups based on their experience of head-loading. They walked over a force plate in three conditions: unloaded or carrying 20 kg in either a backpack or on their head. The most striking finding was that there was no difference in kinetic response to head-loading as a consequence of previous experience. Considering the differences between the load carriage methods, most changes were consistent with increasing load. Head-loading was, however, associated with a shorter contact time, smaller thrust maximum and greater vertical force minimum than back-loading. Both loading conditions differed from unloaded walking for a number of temporal variables associated with the ground contact phase, e.g. vertical impact peak was delayed whilst vertical thrust maximum occurred earlier. STATEMENT OF RELEVANCE: Consideration of the kinetics of head and back load carriage in African women is important from a health and safety perspective, providing an understanding of the mechanical adaptations associated with both forms of load carriage for a group of people for whom such load carriage is a daily necessity.
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Affiliation(s)
- R Lloyd
- Division of Sport and Exercise Sciences, University of Abertay Dundee, UK.
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Xu X, Hsiang S, Mirka G. An empirical validation of a base-excitation model to predict harvestable energy from a suspended-load backpack system. THEORETICAL ISSUES IN ERGONOMICS SCIENCE 2010. [DOI: 10.1080/14639220903373839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Lloyd R, Parr B, Davies S, Cooke C. Subjective perceptions of load carriage on the head and back in Xhosa women. APPLIED ERGONOMICS 2010; 41:522-529. [PMID: 19926071 DOI: 10.1016/j.apergo.2009.11.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2009] [Revised: 10/16/2009] [Accepted: 11/01/2009] [Indexed: 05/28/2023]
Abstract
The purpose of this study was to compare the subjective perceptual responses to both head-loading and back-loading in a group of Xhosa women. Thirty two women were divided into three groups based on their experience of head-loading and walked on a treadmill on two occasions, head-loading and back-loading, at a self selected walking speed for 4 min with a variety of loads until pain or discomfort caused the test to be terminated or a load of 70% body mass was successfully carried. After each workload there was a 1 min rest period during which the women indicated feelings of pain or discomfort in particular areas of the body via visual analogue scales. At the end of each test the women were asked to complete further questionnaires relating to pain and discomfort and on completion of the second test were also asked to compare the two loading conditions. Finally the women were interviewed to establish their history of load carriage and associated pain and discomfort. The data indicate that whilst back-loading was generally associated with more areas of discomfort than head-loading, the pain and discomfort in the neck associated with head-loading was the predominant factor in the termination of tests and that this was independent of head-loading experience. This early termination meant that, on average, the women could carry greater loads on their backs than on their heads. The study suggests that further work needs to be carried out to establish viable alternatives to head-loading for rural dwellers in Africa.
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Affiliation(s)
- R Lloyd
- Division of Sport and Exercise Sciences, University of Abertay Dundee, Dundee DD1 1HG, UK.
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A comparison of the physiological consequences of head-loading and back-loading for African and European women. Eur J Appl Physiol 2010; 109:607-16. [DOI: 10.1007/s00421-010-1395-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/07/2010] [Indexed: 10/19/2022]
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AL-Khabbaz YS, Shimada T, Hasegawa M, Inoue Y. Effects of Wearing a Backpack on Trunk-Lower Limb Kinematics at Start of Gait. J Phys Ther Sci 2010. [DOI: 10.1589/jpts.22.149] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
| | - Tomoaki Shimada
- The Department of Physical Therapy, Faculty of Health Science, Kobe University
| | - Masashi Hasegawa
- The Department of Occupational Therapy, Kansai Sougou Rehabilitation Colleague
| | - Yuriko Inoue
- The Department of Physical Therapy, Kansai Sougou rehabilitation Colleague
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