Insole effects on impact loading during walking

Impact loading during walking has been associated with overuse related musculoskeletal disorders, such as osteoarthritis. This study was designed to determine the effect of two shoe insole designs on impact-related loading during walking. In total, 22 healthy adults walked along a 10-m walkway in three different insole conditions: (i) no insole; (ii) flat material insole; (iii) heel-cup insole. Impact forces at the ground were determined and estimated at the knee in a subset of participants (n = 14). Repeated measures ANOVA revealed a significant reduction in peak vertical ground reaction force (vGRF) with the flat material insole compared with the no insole and heel-cup conditions (p = 0.001). No differences between conditions were observed in vGRF loading rate (p > 0.05). Peak impact force at the knee was reduced with flat material insoles and heel-cup insoles (p < 0.05). These data indicate that reductions in impact forces during walking are dependent upon insole design.

Statement of Relevance: This study provides new evidence that impact loads are reduced with shoe insoles during walking. High impact loads are implicated in the development and progression of knee pathologies, including osteoarthritis. Thus, these findings indicate that insole use may be beneficial for various musculoskeletal disorders, including key public health problems such as osteoarthritis.     

Calf massager: Intervention for body muscle discomfort during prolonged standing

Many occupations require workers to stand for long periods of time without proper interventions, which causes discomfort in the back and lower limbs. Therefore, this study aims to assess the effectiveness in alleviating body muscle discomfort during prolonged standing through the use of a calf massager. This study was conducted among male workers at a manufacturer with production line workers and the list was obtained from the HR Department and simple random sampling was done by number categorization. A total of 100 respondents (50 respondents for both the control and the experimental groups) participated in this study. The experiment took place in a room with a similar setup for the production line. Each respondent was requested to perform the simulated task for 2 hr. For the experimental group, the calf massager was turned on every 15 min. At every 15‐min interval after turning on the calf massager, respondents from both groups were required to evaluate their discomfort level on a Borg's scale CR‐10 questionnaire. The results showed that the level of body discomfort among respondents in the experimental group reduced (20–30%) compared with that of the control group. Multivariate analysis results revealed that the discomfort rating for the lower back, knees, thighs, calves, and feet was significantly lower (p < .05) among the experimental group compared with the control group. For lower body parts, the lower back region was statistically significant (p < .05) at the 90th, 105th, and 120th min; the thigh region was statistically significant (p < .05) at the 120th min; the knee region was statistically significant (p < .05) at the 105th and 120th min; the calf region was statistically significant (p < .05) at all minute intervals except the 15th and 45th min, while the feet region, was statistically significant at the 105th and 120th min. Therefore, this study indicates that calf massage treatment is capable of reducing body muscle discomfort during prolonged standing and highlights the significance of calf massage.     

Changes in stature following plyometric drop-jump and pendulum exercises

The aim of this study was to compare the changes in stature following the performance of plyometric exercises using drop-jumps and a pendulum swing. Eight male participants aged 21.7 ± 1.8 years with experience of plyometric training gave their informed consent to act as participants. Participants undertook two exercise regimens and a 15-min standing test in a random order. The exercises entailed the performance of 50 drop-jumps from a height of 0.28 m or 50 pendulum rebounds. Participants were instructed to perform maximal jumps or rebounds using a ‘bounce’ style. Measurements of stature were performed after a 20-min period of standing (pre-exercise), 2-min after exercise (post-exercise) and after a 20-min standing recovery (recovery). Back pain and muscle soreness were assessed using an analogue-visual scale, at each of the above times and also 24 and 36 h after the test. Peak torque during isokinetic knee extension at 1.04 rads^?1 was measured immediately before and after the exercise bouts, to assess the degree of muscular fatigue. Ground/wall reaction force data were recorded using a Kistler force platform mounted in the floor for drop-jumps and vertically on the rebound wall for pendulum exercises. Drop-jumps resulted in the greatest (p<0.05) change in stature (-2.71±0.8 mm), compared to pendulum exercises (-1.77±0.7 mm) and standing (-0.39±0.2 mm). Both exercise regimens resulted in a significant (p<0.01) decrease in stature when compared to the standing condition. Dropjumps resulted in significantly greater peak impact forces (p<0.05) than pendulum exercises (drop-jumps = 3.2±0.5 × body weight, pendulum = 2.6±0.5×body weight). The two exercise conditions both invoked a small degree of muscle soreness but there were no significant differences between conditions. Both exercise regimens resulted in a non-significant decrease in peak torque indicating a similar degree of muscular fatigue. Based on the lower shrinkage resulted and lower peak forces, it can be concluded that pendulum exercises pose a lower injury potential to the lower back than drop-jumps performed from a height of 28 cm.     

Effectiveness of leg movement in reducing leg swelling and discomfort in lower extremities

Various occupations required that workers stand for long periods, causing discomfort and pain. This study considered the effectiveness of three leg movements in relieving discomfort of the lower extremities during long periods of standing at work. Ten paid male subjects with no history of problems of the lower extremities were enrolled in this study. They performed three leg movements on a hard floor while standing for 4 h in a laboratory setting. Each 1 h experimental test had two phases - 50 min of standing, followed by 10 min of rest. During the period of standing, one the following leg movements was made. No movement (no change in posture), ankle movement (twice, for 2 min each time), and hip movement (twice, for 2 min each time). Observations revealed that the three leg movements yielded different degrees of lower limb swelling. The percentage changes in thigh (1.22%) and shank (1.32%) circumferences were largest during prolonged standing without any movement and lowest during prolonged standing with ankle movement (0.61%) and hip movement (0.80%). The relationship between perceived discomfort and standing time was determined. The subjects perceived the most shank discomfort (5.8) during the 4 h test without any movement. Leg movement greatly influenced perceived discomfort of the shank. The results of this study suggested that workers should move their ankles and hips for a short period following prolonged standing for 30 min to reduce lower extremity discomfort.     

Are arch‐conforming insoles a good fit for diabetic foot? Insole customized design by using finite element analysis

Plantar ulceration is one of the leading complications for diabetic patients. To reduce the risk of plantar ulceration, people with diabetic neuropathy often used custom insoles to offload high pressures from the metatarsal. However, the current custom arch‐conforming insoles, totally contact with the foot, could affect the flow of blood and produce adverse effects on foot ulcers. This study is aimed to propose novel custom insoles for diabetic foot and to make a comparison between the traditional insoles and the proposed one. The novel pressure‐relieving insole is a layered modular insole that includes eight layers of small cushions. The results showed that the current custom insoles would increase the insole volume and squeeze the space available for the foot, and then the constrictive box of the footwear could deteriorate the blood flow of the foot and produce adverse effects on foot ulcers. The novel insoles were found to reduce the peak pressure from 208.86 to 160.02 kPa. High pressure was not observed in the sensitive locations of diabetic foot in this study, and the novel insoles fit diabetic foot better.     

Are hybrid sit–stand postures a good compromise between sitting and standing?

Potential alternatives for conventional sitting and standing postures are hybrid sit-stand postures (i.e. perching). The purposes of this study were (i) to identify where lumbopelvic and pelvic angles deviate from sitting and standing and (ii) to use these breakpoints to define three distinct postural phases: sitting, perching, and standing, in order to examine differences in muscle activations and ground reaction forces between phases. Twenty-four participants completed 19 1-min static trials, from sitting (90°) to standing (180°), sequentially in 5°trunk–thigh angle increments. The perching phase was determined to be 145–175° for males and 160–175° for females. For both sexes, knee extensor activity was lower in standing compared to perching or sitting (p < .01). Anterior–posterior forces were the highest in perching (p < .001), requiring ～15% of body-weight. Chair designs aimed at reducing the lower limb demands within 115–170° trunk–thigh angle may improve the feasibility of sustaining the perched posture.

Practitioner summary: Individuals who develop low back pain in sitting or standing may benefit from hybrid sit-stand postures (perching), yet kinematic and kinetic changes associated with these postures have not been investigated. Perching can improve lumbar posture at a cost of increased lower limb demands, suggesting potential avenues for chair design improvement.

Abbreviations: A/P: anterior-posterior; M/L: medial-lateral; LBP: low back pain; EMG: electromyography; TES: thoracic erector spinae; LES: lumbar erector spinae; VMO: vastus medialis obliquus; MVC: maximum voluntary contraction; ASIS: anterior superior iliac spine; PSIS: posterior superior iliac spine; BW: body weight; RMSE: root mean square error; SD: standard deviation; ROM: range of motion     

A detailed description of the short-term musculoskeletal and cognitive effects of prolonged standing for office computer work

Due to concerns about excessive sedentary exposure for office workers, alternate work positions such as standing are being trialled. However, prolonged standing may have health and productivity impacts, which this study assessed. Twenty adult participants undertook two hours of laboratory-based standing computer work to investigate changes in discomfort and cognitive function, along with muscle fatigue, movement, lower limb swelling and mental state. Over time, discomfort increased in all body areas (total body IRR [95% confidence interval]: 1.47[1.36–1.59]). Sustained attention reaction time (β = 18.25[8.00–28.51]) deteriorated, while creative problem solving improved (β = 0.89[0.29–1.49]). There was no change in erector spinae, rectus femoris, biceps femoris or tibialis anterior muscle fatigue; low back angle changed towards less lordosis, pelvis movement increased, lower limb swelling increased and mental state decreased. Body discomfort was positively correlated with mental state. The observed changes suggest replacing office work sitting with standing should be done with caution.

Practitioner Summary: Standing is being used to replace sitting by office workers; however, there are health risks associated with prolonged standing. In a laboratory study involving 2 h prolonged standing discomfort increased (all body areas), reaction time and mental state deteriorated while creative problem-solving improved. Prolonged standing should be undertaken with caution.     

Prevalence and associated risk factors of low‐back pain in textile fishing net manufacturing

This study examined the 7‐day prevalence of low‐back pain (LBP; i.e., pain within the preceding week of the survey) and identified associated factors, including working posture, for a population of fishing net assembly workers. LBP is a serious problem in manual work with high prevalence and affects worker absenteeism. A cross‐sectional survey study was conducted among textile fish net industrial workers using a structured questionnaire (hand delivered by researchers and independently completed by workers). The 7‐day prevalence of LBP in this study was 68.6% (95% confidence interval [CI]: 65 to 72%). Work factors significantly related to LBP included prolonged standing and walking. Workers 35 years old or greater were significantly more likely to experience LBP within the past 7 days preceding the survey than were those 34 years old or less (adjusted odds ratio [ORadj] = 4.9; 95% CI: 2.4 to 10.3; p = .0001). Other significant factors associated with LBP included posture position, specifically stooping (ORadj = 1.6; 95% CI: 1.0 to 2.3; p = .033), lifting (ORadj = 1.6; 95% CI: 1.1 to 2.4; p = .025), and high concentration jobs (ORadj = 1.9; 95% CI: 1.3 to 2.7; p = .001), respectively. LBP among textile fish net workers is a serious problem meriting ergonomic evaluation and design of control measures for reducing worker exposure to risk factors. Work characteristics were more significantly associated with LBP than were individual characteristics. Factories need to consider adjusting work conditions to prevent worker low‐back injuries. © 2012 Wiley Periodicals, Inc.     

Spinal shrinkage,sagittal alignment and back discomfort changes in manufacturing company workers during a working day

Abstract

Prolonged standing and lifting heavy loads are risk factors for the appearance of low back pain in work. The aim of this study was to observe changes in the height, spinal sagittal alignment, and the lumbar and dorsal discomfort perception in assembly line workers. Cross-sectional study, 40 assembly line workers (6 females). Height, sitting height, grades of thoracic kyphosis and lumbar lordosis and perceived spine discomfort, before and after the working day, were determined. Thoracic and lumbar sagittal alignment was compared between discomfort developers and no developers. There was a significant decrease in the height and sitting height of the workers at the end of the day. Thoracic and lumbar curvature increased significantly, as did the perceived lumbar discomfort. Workers on the assembly line, in a prolonged standing work, suffer an increase in lumbar discomfort, and changes in height and thoracic and lumbar curvatures.

Practitioner summary: Spinal shrinkage, sagittal alignment and back discomfort (upper and lower back), were analysed in assembly line workers in prolonged standing during a workday. Assembly line workers suffer a decrease in height, an increase in their thoracic and lumbar curvature, and in lumbar discomfort throughout their workday.     

Comparing standing posture and use of a sit-stand stool: Analysis of vascular,muscular and discomfort outcomes during simulated industrial work

Sit-stand stools are available for use in industrial settings, but there is a lack of quantitative evidence demonstrating benefits for lower limb, back and/or neck/shoulder outcomes. In this paper we describe an experiment conducted to compare and contrast posture and time-related differences in muscular and vascular outcomes during 34 min of manual repetitive work performed in either standing or sit-standing work posture. We measured vascular parameters in the lower limbs, and muscular parameters in the trunk and neck/shoulder, and discomfort in the three regions as participants accomplished a repetitive box-folding task. Results show that blood flow in the foot (p = 0.022) and ankle mean arterial pressure (p < 0.001) were greater during standing. Left gluteus medius and external oblique activation was higher during standing, while sit-standing work resulted in higher levels of co-activation between the left erector spinae and external oblique muscle pair (p = 0.026). Neck/shoulder muscle activity was not significantly different between the conditions. Reported discomfort did not differ significantly for the trunk and neck/shoulder region, but standing resulted in higher level of reported discomfort in the lower limb. The sit-stand posture used in this experiment appears to prevent the undesirable lower limb outcomes associated with static standing work posture.Relevance to industryThis work demonstrates quantitative evidence to support the potential use of a sit-stand stool for industrial work operations, at least over relatively short durations.     

Influence of foot orthosis customisation on perceived comfort during running

Although running is associated with many health benefits, it also exposes the body to greater risk of injury. Foot orthoses are an effective strategy to prevent such injuries. Comfort is an essential element in orthosis design since any discomfort alters the runner's biomechanics, compromising performance and increasing the risk of injury. The present study analyses the perceived comfort of three types of orthoses: custom-made, prefabricated and original running shoe insoles. Nine comfort variables for each insole were assessed in a sample of 40 runners. Custom-made and prefabricated insoles were both perceived as significantly more comfortable than the original insoles. The differences were clinically relevant and were potentially causes of modifications in running gait. Although the prefabricated insoles were rated slightly higher than the custom-made insoles, the differences were not statistically significant. This study shows that prefabricated insoles constitute a reasonable alternative to custom-made insoles in terms of comfort.     

Prevalence of musculoskeletal disorders (MSDS) among primary school female teachers in Terengganu,Malaysia

BackgroundMusculoskeletal disorders (MSDs) has been a well-known occupational health issue for workers over recent years, and the prevalence among school teachers is particularly high. In Malaysia, few studies are focusing on MSDs and associated factors among school teachers, but in Terengganu, there is no data available for MSDs among school teachers. Objectives: To identify the prevalence of MSDs and associated risk factors among female teachers in Terengganu primary school. Methods: Data collection was carried out with a self-administered questionnaire. A total of 212 female school teachers participated in this study. Results: The findings show that the prevalence for any parts of the body was 40.1%. The most affected part of the body was feet, with 32.5% for the past 12-months and 36.8% for the past 7 days. The most significant risk factors that associated with body parts (lower back, thigh, calf, knee, and feet) were age, BMI, sports activity, shoe type, teaching hours, and standing hours during school. Conclusion: Female teachers in Terengganu's primary school had shown a significant prevalence of musculoskeletal disorders. The most affected body parts were feet, followed by knee, upper back, and lower back. Related risk factors such as age, BMI, sports activity, type of shoe, teaching hours and standing hours were analysed. Hence, they are prone to have higher MSDs prevalence than current results due to significant risk factors if there is no measure taken to reduce MSDs prevalence among teachers.     

Influence of pressure-relief insoles developed for loaded gait (backpackers and obese people) on plantar pressure distribution and ground reaction forces

The aims of this study were to test the effects of two pressure relief insoles developed for backpackers and obese people on the ground reaction forces (GRF) and plantar pressure peaks during gait; and to compare the GRF and plantar pressures among normal-weight, backpackers, and obese participants. Based on GRF, plantar pressures, and finite element analysis two insoles were manufactured: flat cork-based insole with (i) corkgel in the rearfoot and forefoot (SLS1) and with (ii) poron foam in the great toe and lateral forefoot (SLS2). Gait data were recorded from 21 normal-weight/backpackers and 10 obese participants. The SLS1 did not influence the GRF, but it relieved the pressure peaks for both backpackers and obese participants. In SLS2 the load acceptance GRF peak was lower; however, it did not reduce the plantar pressure peaks. The GRF and plantar pressure gait pattern were different among the normal-weight, backpackers and obese participants.     

Specific flexion-related low back pain and sitting: comparison of seated discomfort on two different chairs

No study has examined the effectiveness of prescribing seating modifications according to the individual clinical presentation of people with low back pain (LBP). A dynamic, forward-inclined chair (‘Back App’) can reduce seated paraspinal muscle activation among pain-free participants. This study examined 21 participants whose LBP was specifically aggravated by prolonged sitting and was eased by standing. Low back discomfort (LBD) and overall body discomfort (OBD) were assessed every 15 min while participants sat for 1 h on both the dynamic, forward-inclined chair and a standard office chair. LBD increased significantly more (p = 0.005) on the standard office chair, with no significant difference (p = 0.178) in OBD between the chairs. The results demonstrate that, in a specific flexion-related subgroup of people with LBP, increased LBD during sitting can be minimised through modifying chair design. Mechanisms that minimise seated discomfort may be of relevance in LBP management, as part of a biopsychosocial management plan.

Practitioner summary: This study examined low back discomfort (LBD) during a typing task among people with low back pain (LBP). Sitting on a dynamic, forward-inclined chair resulted in less seated LBD than sitting on a standard office chair. Further research is required to examine the long-term effectiveness of ergonomics interventions in LBP.     

Effects of low back disability status on lower back discomfort during sustained and cyclical trunk flexion

A laboratory study was conducted to determine the effects of back disability status on endurance time and perceived discomfort during trunk flexion. Eighty participants (40 with chronic or recurrent low back pain (CRLBP), 40 pain-free) were tested. The trunk was flexed to 15°, 30°, 45° and 60° under three conditions: 1) continuous static flexion; 2) cyclical flexion with 20% rest; and 3) cyclical flexion with 40% rest. Each condition was performed for up to 600?s or until the participant reached his/her pain tolerance limit. Dependent variables included time to distracting discomfort (TDD), total endurance time (TET) and perceived discomfort. For continuous exertions, CRLBP participants had lower TDD (p?<?0.001), lower TET (p?<?0.001) and greater discomfort (p?<?0.001) compared to pain-free controls. In both groups, TDD and TET decreased and perceived discomfort increased as the flexion angle increased. For intermittent exertions, CRLBP participants reported greater discomfort than pain-free participants (p?<?0.001). Increasing rest from 20 to 40% reduced discomfort in CRLBP participants, but produced no consistent benefit in pain-free participants. To accommodate persons with CRLBP, consideration should be given to reducing both the magnitude (angle) and duration of trunk flexion required by their jobs.     

Effects of sitting versus standing and scanner type on cashiers

In the retail supermarket industry where cashiers perform repetitive, light manual material-handling tasks when scanning and handling products, reports of musculoskeletal disorders and discomfort are high. Ergonomics tradeoffs exist between sitting and standing postures, which are further confounded by the checkstand design and point-of-sale technology, such as the scanner. A laboratory experiment study was conducted to understand the effects of working position (sitting versus standing) and scanner type (bi-optic versus single window) on muscle activity, upper limb and spinal posture, and subjective preference of cashiers. Ten cashiers from a Dutch retailer participated in the study. Cashiers exhibited lower muscle activity in the neck and shoulders when standing and using a bi-optic scanner. Shoulder abduction was also less for standing conditions. In addition, all cashiers preferred using the bi-optic scanner with mixed preferences for sitting n = 6) and standing (n = 4). Static loading of the muscles was relatively high compared with benchmarks, suggesting that during the task of scanning, cashiers may not have adequate recovery time to prevent fatigue. It is recommended that retailers integrate bi-optic scanners into standing checkstands to minimize postural stress, fatigue and discomfort in cashiers.     

An air-spring standing platform does not increase overall movement or metabolic cost during simulated work tasks

Due to the increased popularity of standing-based occupational work stations there is a growing need to understand the impact of ergonomic aids such as standing mats. In particular, while standing mats have been studied in relation to musculoskeletal discomfort and pain, there have been no studies exploring the effects of their use on metabolism and caloric expenditure. The purpose of this study was to examine the metabolic, biomechanical, and pain/discomfort responses to the use of an air-spring standing mat over a 2-h work-simulated standing period. Sixteen participants visited the lab on two separate occasions, each to perform a 2-h standing simulated-work session, once with and once without a standing mat. Metabolic data were recorded at the start, midpoint, and end of the standing sessions. Force plate centre of pressure (COP) and visual analog discomfort score (VAS) measurements were taken every 15 min. Results demonstrated that there was no difference in caloric expenditure between the two sessions. COP variables demonstrated less movement on the standing mat compared to the control day; however, only one of the eight variables (root-mean-square velocity in the medial-lateral direction) was statistically significant (p = 0.02). VAS scores showed no clear benefit of the standing mat on low back or lower limb discomfort. The short-term introduction of an air-spring standing mat during simulated work tasks appears to have no clear benefits on energy expenditure, biomechanical centre of pressure variables, or for alleviating musculoskeletal discomfort. Whether longer term exposure to this type of mat has differential effects remains to be addressed.     

Influence of shoe/floor conditions on lower leg circumference and subjective discomfort during prolonged standing

Many occupations require workers to stand for prolonged periods, which can cause both discomfort and pain. This study examines the effects of different shoe and floor conditions on standing discomfort in the workplace and laboratory. Two experiments were conducted. Experiment 1 enrolled 10 subjects who performed a computer task under two floors and shoe conditions while standing for 4 h in a laboratory. Experiment 2 involved 14 subjects who stood for 4 h throughout their shift on two different floors in a real work situation (i.e., a field experiment). Analytical results demonstrate that floor type and time standing significantly affected subjective ratings for leg discomfort and circumferential shank measurements in both the laboratory and field studies. Shoe condition significantly affected subjective ratings for leg discomfort. We conclude that shoe/floor conditions and prolonged standing influence worker lower extremity discomfort during prolonged standing. These analytical findings suggest that common ergonomic interventions, such as modifying the flooring on which workers stand might some what alleviate leg edema for workers standing for 4 h shifts in laboratory and field settings. Nevertheless, prolonged standing for even 1 h without rest showed negative effects and should be avoided when possible.     

Ergonomic risk factors in glass artware industries and prevalence of musculoskeletal disorder

Glass artware manufacturing activities are highly repetitive, labor-intensive, and demand prolonged standing during the working shift. This leads to the development of musculoskeletal disorders (MSDs) symptoms among the workers. However, there is a scarce of study on the prevalence of MSDs symptoms and their associated risk factors among the glass artware workers. To address this research gap, this study aims to evaluate the prevalence of MSDs and working conditions among Indian glass artware workers. Discomfort data is collected using Cornell Musculoskeletal Discomfort Questionnaire and working posture data is collected through direct observations using Rapid Entire Body Assessment (REBA). Multiple logistic regression model is developed for each body region to study the relationship between the associated risk factors and MSDs symptoms with the help of collected data. The findings of this study are first, MSDs symptoms are highly prevalent and severe, particularly in the lower back, thigh, and foot. Second, the average REBA grand score is 7.22, which reveals the high-risk level of worker's posture while performing the task. Third, Job characteristics and individual factors are associated with MSD symptoms in multiple logistic regression models. The results highlight the prevalence and severity level of MSDs and illustrate the demand for ergonomic interventions to alleviate musculoskeletal symptoms among these working groups.Relevance to industryThis study draws attention to work-related and other associated risk factors, which would help the researchers and managers to understand the working environment of glass artware industry. These risk factors should be considered for designing and implementing ergonomic interventions to prevent and alleviate musculoskeletal discomfort among the glass artware workers.     

A comparison of the effects of floor mats and shoe in-soles on standing fatigue

In assembly line positions and other occupations, employees experience pain and discomfort associated with long periods of standing. Modifying flooring is a common intervention method used to alleviate problems associated with constrained standing. This study investigated the effects of four different standing conditions upon assembly workers' perception of general fatigue and discomfort associated with various body parts following 1 week of 8-h days of exposure to each condition. The four standing conditions were (1) on hard floor, (2) on a floor mat, (3) wearing shoe in-soles, and (4) wearing shoe in-soles while standing on a floor mat. Questions were asked regarding general fatigue and discomfort. In general, the mat, in-soles and combined conditions were more comfortable than standing on hard floor. Moderately strong correlations were found for the variables of height, age and job tenure. Shorter individuals experienced greater discomfort in the upper leg and low back when standing on a mat and when wearing in-soles. The older workers and those with more job seniority reported greater discomfort associated with body joints when standing on the hard floor and when standing on the floor mat. No significant differences in fatigue or discomfort were found when comparing the overall effects of using the floor mat to wearing the shoe in-soles or the combined condition.