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This paper examines an approach to modeling the relationship between perceived acceptable work exposures and physical stressors in upper-extremity tasks using psychophysical methods. Several years of laboratory-based studies and results from a variety of simulated work tasks and task elements are summarized. The original impetus of these studies was founded in the pioneering work and successful application of psychophysical methods applied to manual materials handling tasks (e.g., lifting) generally beginning in the 1960s and 1970s. This approach provided unique and feasible solutions to work design problems involving exposure to the hazard of cumulative trauma. Presently, these methods were adapted to studying common upper-extremity tasks and task elements. Results provide conclusive evidence of the impact of required posture, force, gender and other variables on acceptable task frequency. These results and the psychophysical method in general, may be particularly helpful in establishing realistic and reasonable work design guidelines when workers are exposed to multiple, simultaneous hazards such as force, frequency, with deviated posture, etc, and in the absence of well-defined biomechanical or physiological-based models. Finally, a review of psychophysical theory and methods which can be applied to a wide range of occupational activities is provided. Relevance to industry Psychophysical methods have been utilized for realistic work design guidelines for jobs with risk of musculoskeletal disorders, particularly the low back. This paper summarizes psychophysical methods and results developed for upper-extremity tasks. Required task frequencies should be reduced when postural deviation, required force, and other factors such as vibration, are greater than nominal.

The primary goal of the ergonomist is to develop systems and products that increase productivity, function intuitively, and minimize the user’s risk of injury and illness. Injuries occur when a system or product does not fit or was not designed for the capabilities of the user. The physical ergonomist plays an important role in litigation in reducing the risk of large damages or settlements through improved design. This article outlines three cases that demonstrate how a physical ergonomist uses established methods and techniques to analyze litigation cases.

The NIOSH Lifting Equation, specifically the 1991 Revised Lifting Equation or RLE (Waters et al., 1993) is used worldwide by occupational ergonomists, industrial engineers and safety specialists to assess and (re)design manual lifting tasks and industrial systems that involve either single or repetitive lifting. Since the initial publication of the RLE, there have been a number of published studies on its usability, effectiveness and validation. The purpose of this panel discussion will be to critically review these RLE-related studies and examine implications of applying the RLE in various occupational settings and working populations. The first of four presentations will summarize recent epidemiological studies that have quantified exposure-response relationships between the RLE and incidence of low-back pain-related care and medication use issues, and discuss the RLE implications for job surveillance, intervention, and design approaches. The second presentation discusses practical relevance of the RLE and issues surrounding its sensitivity and specificity in correctly identifying hazardous lifting tasks. The third presentation will critically examine the conservativeness of the recommended weight limit derived from RLE by comparing the output of the RLE with the output from the specific biomechanical, psychophysical and physiological criteria utilized in its initial development of the lifting equation. Although application of the RLE has exponentially grown since its inception, the final presentation explores its feasibility in applying it to a non-US work force. The primary audience for this session will be occupational ergonomists who utilize the NIOSH equation for job assessment and (re)design, although the discussion should be of interest to researchers as well. The overall goal of this Part 1 symposium is to provide RLE users with some practical suggestions and recommendations.

Poor balance is one of the most common risk factors for falling, a common cause of work-related injury and death. To evaluate the effects of a 10-week intervention program on balance in older adults, 12 participants aged 61–77 years (age = 70.4 ± 5.4 years; mean ± SD) completed an exercise program (60 min, 2 days · week−1 for 10 weeks) performed while laying/sitting on large air-filled exercise balls (Thera-Band®). Several postural sway composite scores (determined while standing with feet apart and semitandem, eyes open and closed) improved (p ≤ 0.05) including medial–lateral amplitude and speed of sway (reduced by ∼9%), and instantaneous speed (reduced by ∼13%). Reductions in XY area approached (p = 0.06) statistical significance and anterior–posterior amplitude and speed of sway did not change. Functional reach also improved (20.3%). These results suggest that challenging the physiological systems involved in balance control while on the nonstable support surface of the exercise balls improves both static and dynamic balance in older adults and may reduce the risk for falling.

This study examined the effects of aging on performance and preferences for two computer pointing devices (e.g. mouse and trackball). Participants made simple point-and-click and click-and-drag movements to targets of varying distance (96 and 192 mm) and widths (3, 6 and 12 mm). The results show that older adults (mean age=70) moved more slowly than younger adults (mean age=32), particularly for distant targets, yet their movements were less variable. No age differences were found in movement time or variable error between the two devices. EMG (RMS) recordings from the forearm flexor and extensor muscles showed no age related differences in between mouse and trackball. However, ratings of perceived exertion (RPE) indicated that older adults perceived greater levels of exertion than younger adults when using the mouse during click-and-drag tasks. Given the reduced grip and pinch force of older adults, manipulation of the mouse and trackball required a greater percentage of their maximum voluntary contraction (MVC) compared to younger adults. In addition, the mouse requires a larger range of motion than the trackball. These findings in conjunction with the RPE results imply that the trackball may confer greater benefit for the older computer user. Relevance to industry The work force is growing older and the selection of appropriate computer input devices is important to reduce injury and improve or maintain productivity.

This paper consists of three different investigations which focused on the implementation of an arm support system and its effect on the level of pain and/or discomfort experienced by subjects while completing either a light assembly or a computer typing task. The types of arm support systems included no arm supports, Ergorest articulating arm supports, chair arm supports at maximum breadth, midpoint breadth, minimum breadth, and counter-balanced arm slings. Results indicated that arm supports significantly impacted comfort, effort required, RPE, EMG activity, and heart rate. It was concluded that in light assembly and computer work tasks, an arm support system would be recommended to minimize effort and RPE, and to maximize comfort. Relevance to industry Computer use and light assembly work are an integral part of various workplaces which often require employees to work in constrained unsupported postures, at repetitive tasks and in precision work with hands, arms and fingers. This paper proposes a solution that could aid individuals in these environments.

The international globalization of the World markets for manufactured goods, particularly consumer goods, has placed an emphasis on nations to improve manufacturing productivity. This need to improve productivity is further prompted by a potential loss of competitive edge in the global marketplace. The market competitiveness and e$ciency of any nation is primarily dependent upon the economy, reliability, quality, quickness, and ease of its manufacturing processes and the resulting quality of outcomes (products). To a major extent, the skills of the workforce determine the e!ectiveness and the e$ciency of the process of manufacturing and the quality of goods produced. And yet, there is a severe lack of standardized and consistent worker training programs for skills needed by workers in modern manufacturing organizations. This review paper shows that there is a dire need to train workers in manufacturing organizations and thereby improve the overall e!ectiveness and e$ciency of such organizations. Relevance to industry As technology changes, so do the skills workers need. In order to compete successfully in the global market, manufacturing organizations must aim at training workers in skills necessary to produce quality goods. ( 1999 Elsevier Science B.V. All rights reserved.

In the aircraft industry, the design of floor assembly jigs (FAJs) is an important activity that directly affects productivity. It involves tool frame generation and locator and clamp placement to ensure that the assembly components are held properly with respect to each other to meet the required tolerances. The tool designer also has to analyze the design to ensure that the assembly process does not pose accessibility and ergonomics related problems. The current approach is dependent on the experience of the tool designer and the limited visualization possible on commercial CAD systems. This leads to extensive redesign when accessibility and ergonomic related problems are detected on the physical prototype. In this research, an integrated Virtual Reality-based environment is being developed for the analysis of assembly product and jig designs. CAD models of the assembly product and jig are imported into a Virtual Reality (VR)-based visualization system for accessibility analysis. A motion tracking system is integrated to allow ergonomic posture analysis. The combined VR and motion tracking system allows evaluation of alternate assembly sequences and the jig design. In this paper, the theoretical basis for the analysis environment is presented along with details of the prototype implementation of this system. Relevance to industry Floor assembly jigs are used extensively by the aircraft industry. Improvement of their design process will lead to savings in better design and reduced development time and cost. Better designs will require fewer changes after the jigs have been fabricated. The overall result will be a reduction in product realization time and cost and improved product quality.

A laboratory experiment was conducted to determine maximum acceptable task frequencies (MAF) for males performing a simulated riveting task at different wrist postures and applied force levels using an operational rivet gun. Twelve healthy males from a university population served as subjects. Results indicated that MAF decreased significantly with a deviation in wrist posture and an increase in applied force. These results were supported by various physiological variables and ratings of perceived exertion. It was also determined that decrements in MAF due to vibration were 36% while decrements due to wrist posture were 19%. This would indicate that vibration, as a risk factor in the development of work-related musculoskeletal disorders, is of more concern than wrist posture. Implication of the findings are discussed in the body of the paper. Relevance to industry Ergonomic intervention may decrease the development of work-related musculoskeletal disorders thus reducing workers compensation costs and lost productivity of the worker.

Manufacturing experiments with full automation for manufacturing of goods, developed, promoted and attempted in the 1980s, have failed for economic and technical reasons. It is now widely accepted ...

This study investigated age-related differences in user performance and preferences using two widely available computer pointing devices, a mouse and trackball. Participants acquired on-screen targets of varying distance and size using point-and-click and click-and-drag motions. It was found that older adults took longer to complete movements than younger adults and did so to a greater extent for large amplitude movements, but that their movements were less variable. There was no age difference in movement time or variable error between the two devices. It has been hypothesized that the findings reflected the adoption of a device independent movement strategy by the elderly designed to compensate for age-related declines in motor control. Analysis of muscle activity (RMS) of the forearm flexor and extensor showed no age-related differences in muscle activity. Ratings of perceived extertion revealed that older adults reported higher levels of exertion than younger adults using the mouse during click-and-drag motions. In light of findings demonstrating that older adults have lower strength, this finding implies that the mouse requires a greater percentage of the elderlys' maximum force. These results taken together suggest that the trackball may be a better device for the elderly computer user especially when performing frequent, repetitive actions for prolonged periods of time.

The objective of this study was to determine the optimum time in an 8 h work day for evaluating the comfort rating of chairs. Twelve female subjects were assigned the task of evaluating three types of chairs. The evaluation was conducted using the 11 point general comfort rating scale, which was administered to the subjects at 12 different times in an 8 h work day. The results showed that the comfort rating obtained at the end of the third hour of work was not significantly different from that obtained at the end of 8 h of work. Thus, we can conclude that comfort ratings obtained at the end of 3 h of work should be used for the subjective evaluation of a chair for a typical work day, as it saves time and ensures the selection of ergonomically appropriate seating which in turn could reduce the risk of CTDs. Relevance to industry Improper seating has been the major risk factor for the occurrence of low back and upper extremity cumulative trauma disorders in the office environment. Appropriate evaluation and selection of seats could reduce this risk.

A laboratory experiment was conducted utilizing the psychophysical approach to establish the maximum acceptable frequency (MAF) for a pinching task. The type of pinch used was the lateral pinch. The psychophysically adjusted pinching frequency was determined by the method of adjustment for each of 18 combinations of wrist posture, force, and duration. Twelve healthy males served as subjects. The results indicated that the MAF was significantly reduced as the angle of wrist flexion, pinching force, and task duration increased. This decrease was exponential, not linear. These results were supported by the EMG analysis and the ratings of perceived exertion and body discomfort. The upper limit for mean intensity in this study was 12.7%. If the criteria for acceptability can be defined in terms of the absence of EMG signs of fatigue and low subjective ratings, then the tasks involving 23 maximum wrist flexion, 50% MVC, and/or 7 second task duration were not acceptable. These results are similar to those found in other studies involving different types of hand/wrist work. Relevance to industry The results of this study will be useful in determining acceptable or alternative job designs for many hand/wrist tasks which involve pinching.

The objective of this study was to determine and document the position of peak grip strength in different shoulder, elbow, and wrist posture combinations. Fifteen (15) male subjects performed maximal exertions with their dominant hands in nine wrist postures, three elbow postures, and two shoulder postures. Analysis of the data revealed that shoulder and elbow angles had significant effect upon the grip strength. Similarly, it was seen that grip strength at elbow at 135 degrees flexion was significantly different from those with elbow at 90 and 180 degrees. Further, the results revealed that peak grip strength occurred at a combined posture of shoulder abducted 0 degrees, elbow flexed 135 degrees, and the wrist in the neutral posture. Decrements of up to 42% in grip strength could be seen as elbow and wrist angles deviated. This means that use of handtools at deviated postures of shoulder, elbow, and wrist would decrease the percent of MVC at which a worker operated. Hence, the implementation of the finding of this study might be a reduction in the risk of injury, increase in productivity, and well-being of the workers.

Cumulative trauma disorders (CTDs) of the upper extremities are one of the major ergonomics areas of research. Pinching is a common risk factor associated with the development of hand/wrist CTDs. The capacity standards of peak pinch strength for various postures are needed to design the tasks in harmony with the workers. This paper describes the formulation, building and comparison of pinch strength prediction models that were obtained using two approaches: Statistical and artificial neural networks (ANN). Statistical and ANN models were developed to predict the peak chuck pinch strength as a function of different combinations of five elbow and seven shoulder flexion angles, and several anthropometric and physiological variables. The two modeling approaches were compared. The results indicate ANN models to provide more accurate predictions over the standard statistical models.

Defines ergonomics and discusses various issues such as anthropometry, seat design, workplace principles, manual materials handling, and cumulative trauma disorders. These important issues need to be appreciated if the objective of the facilities manager is to reduce work‐related injuries, improve productivity, and improve the quality of life of the workers.

The purpose of this study was to determine age-related changes of joint range of motion (ROM). Twenty-three joint ROM measurements based on descriptions given in the handbook of the American Academy of Orthopaedic Surgeons (1965) were performed bilaterally (where appropriate) on fifty-five Caucasian males. The group was divided into three age subgroups. The subgroups consisted of twenty-five to thirty-four years, thirty-five to forty-four years, and forty-five years to fifty-years old males. Motion was measured to the nearest one degree. Measurements were repeated until two readings within 4 degrees were obtained. Results indicated a decrease in joint ROM with age, with decreases from 4% to 30%. Right versus left side ROM were different for the wrist and glenohumeral joints. This implies that the aging population with reduced ROM may be at a higher risk of injury for manual material handling and cumulative trauma disorders.

A laboratory experiment was conducted to determine the maximum acceptable frequency (MAF) for a simulated gripping task at different gripping forces and gripping durations using a psychophysical protocol. A modified Lafayette handgrip dynamometer was used to simulate the gripping task for twelve female subjects. Results show that MAF was significantly reduced as gripping force and gripping duration increased. Also, the various physiological responses, EMG analyses, and ratings of perceived exertion supported the MAF values obtained using the psychophysical approach. MAF values for gripping task can be applied in many industrial tasks for the reduction of risk factors for cumulative trauma disorders of the upper extremities.

The effect of training on the physical work capacity (PWC) and the physiological response to simulated tasks of seven ambulatory individuals with cerebral palsy (CP) were studied. Energy demand for each work task was determined by percentage of PWC (%PWC). Results indicate that an eight week training program increased the PWC as evaluated by an exercise test on the Schwinn Air-Dyne Ergometer. The performance of the individuals for the simulated tasks measured in %PWC increased significantly, suggesting that individuals with CP could benefit from a training program and would be able to work eight hours before experiencing fatigue.

This article presents a statistical process control (SPC) approach to reduce the risk of carpal tunnel syndrome (CTS) and the cost of CTS which is estimated at about $3,500 per case. The proposed statistical problem-solving procedures are used to identi..

This paper presents the results of an anthropometric survey conducted on South Indian male workers in the electronic industry. The data were collected as part of a project to modify work stations that utilized equipment from other countries. A set of 27 body dimensions were taken from a sample of 128 workmen (aged 18-35 years). The anthropometric measurements are compared with those of Indian men from Central, Western, and Northern parts of India and with those of the American, German, and Japanese men. The results indicate that in general the South Indian man is smaller than Central, Western, and Northern Indian men, as well as smaller than men in America, Germany, Japan, and Africa. This difference needs to be allowed for when considering buying and subsequently using imported equipment for the electronics industry in South India.

A laboratory experiment was conducted using the psychophysical approach to determine maximum acceptable frequency (MAF) for a simulated sheet metal drilling task under varying angles of wrist flexion. Fifteen male students served as subjects for this study. The subjects were asked to perform a simulated drilling task in five different wrist flexion postures. Results indicated that MAF was significantly reduced (p

This study investigated the effectiveness of a training program for cerebral palsy (CP) adults engaged in full-time employment (8 hrs/day) that would improve their functional capacity. Seven ambulatory CP adults (5 men, 2 women, age 30.5 + 8 yrs) trained on a Schwinn Air-Dyne ergometer (SAE) twice a week for 30 minutes at 40-70% of peak VO2 for 8 weeks. Pre- and posttraining exercise tests were performed on the SAE and an arm crank ergometer. Following training, significant increases (p2 and peak ventilation (VE) were seen, with no significant increases in peak heart rate (HR) or respiratory quotient (RQ) on the SAE. No significant increases in peak VO2, HR, VE, or RQ were seen when exercised on the arm crank ergometer following training. The results indicate that the training protocol used in this study allowed ambulatory CP adults to exercise consistently and safely while demonstrating improvements in functional capacity. Although the mode of exercise involved the arms, the training program did not improve the exercise capacity of the upper body, as evaluated by arm crank ergometry.

An experimental study was conducted to evaluate the grip and fingertip pinch strength, and range of motion of females with carpal tunnel syndrome (CTS). The range of motion of the wrist was measured in the sagittal, frontal, and transverse planes. Strength and range of motion measurements were also conducted on a control group. Results indicate that some strength and range of motion measures of the females with CTS were significantly different from that of the control group. Also, measurements in different planes caused significant differences in some range of motions of the wrist for both the CTS and the control groups.

An experiment was conducted to determine isokinetic wrist flexion and extension strengths of females diagnosed with carpal tunnel syndrome (CTS). Static strength measures were also documented. These values were compared to values from a matched control group. Results show a significant reduction in isokinetic wrist flexion force, grip and tip pinch strengths within the CTS group compared to the controls. Range of motion in wrist flexion also showed a significant decrement for the CTS group. Finally, regression models were developed to predict isokinetic strength based upon static measures.

E-CAFFS is a rule-based expert system for fixturing on a CAD system using flexible fixtures. It accomplishes the automatic layout of fixture models on a CAD/CAM system for given applications through an interative process. The final fixtured simulation is graphically represented as solid models on the screen of a computer-aided design system. This paper focuses on the fixturing of planar polyhedral workpieces for face-milling operations and predicts the feasibility of a generalized expert fixturing strategy on CAD systems. The software developed as a result of this research has decreased fixturing costs by a substantial amount and has successfully reduced fixturing down-time to a mere fraction.

The effectiveness of using portable spirometric techniques on cerebral palsied (CP) individuals to measure lung capacity was investigated. Nondisabled and CP individuals were administered field spirometric tests. There were significant differences between the populations in forced vital capacity (FVC) and one-second forced expiratory volume (FEV/sub 1/) but not between the FEV/FVC ratios. The results suggest that CP individuals could have a restrictive rather than obstructive pulmonary impairment. >

The purpose of this study was to report normative values of the amplitude of joint wrist motions and grip strength for older age groups.Volunteers. (N = 147) were divided into four age groups, 60-69, 70-79, 80-89 and 90+ years, with a total of 62 men and 85 women. Maximum range motion values were obtained for wrist flexion, extension and ulnar deviation. In addition, grip strength measures were obtained for each participant.In general, the strength and ROM values for the oldest participants in this study were lower than those of the younger age group (age 60 to 69) and significantly lower than those published for subjects between 25 and 54 years of age. Furthermore, across all age groups males were significantly stronger than females. However, females tended to have greater ROM than males, particularly for wrist extension and ulnar deviations. Joint ROM and grip strength declined significantly with age for both males and females. Comparisons with published data for younger subjects (age 25-35) indicate that a 60-69 year old male, will on average experience a decline in wrist flexion, extension and ulnar deviation of 12%, 41%, and 22% respectively. By age 90, an individual may be expected to have ROM values that are only approximately 60% of an average 30 year old individual.The results suggest that the ageing population (particularly men) may face greater difficulty using an input device such as a mouse that relies on motions of the wrist. In addition, the reduced ROM of the wrist may put the elderly at greater risk of developing cumulative trauma disorders. The implications of these findings for the design of input devices are discussed.

The accommodation of a task to the unique abilities of an individual with a disability is becoming increasingly the responsibility of the employer. Functional capacity evaluation (FCE) provides the information necessary for rational design decisions when modifying work stations. The currently used FCE systems have been designed to assess an individual's performance for a range of reasons other than industrial task accommodation. The Available Motions Inventory (AMI) is a system that has been developed specifically to address the design issues raised when accommodating an industrial task to a person with a neuromuscular impairment. This system has a unique scoring system that allows intra-individual ability comparisons that support task allocation decisions. Some general principles of task design are developed for persons with cerebral palsy, but the strength of assessment lies in its application to a specific individual performing a specific task.

The effects of music amplitude on participants' response time to randomly presented, unexpected, visual events were investigated. Ninety participants completed a motor-reaction task without music and with music played at 60, 70. or 80 dBA. Males preferred more intense music than females did, with males selecting a comfort level of 72 dBA and females, 66 dBA. However, participants' reaction time and the total time to respond to a randomly activated red light were independent of gender. All participants responded more quickly when the music was played at 70 dBA (close to their comfort level) than when it played at lower (60 dBA) or higher (80 dBA) amplitudes. It is proposed that people may react more quickly to visual events (e.g., the sudden appearance of a plane on the screen of an air traffic controller, or the unpredictable activation of a car's rear brake lights when driving) with music playing at a volume preset to maintain individual comfort levels against other situational background noise.

Two laboratory experiments were conducted; first, to utilize the psychophysical approach (method of adjustment) to establish maximum acceptable frequency (MAF) for a sheet metal drilling task and, second, to examine the effect of sustained, static exertion upon objective and subjective measures under similar task conditions. In both experiments, the wrist posture (flexation, ulnar deviation) required by the task was varied. Twelve healthy females served as subjects. Results show that the psychophysically adjusted task frequency was significantly lower when wrist deviation was required, particularly flexion. MAF for one-third (25 degrees) and two-thirds (50 degrees) flexion were 88% and 73%, respectively, of those selected in the neutral posture. Furthermore, these results were supported by trends in grip strength, heart rate, blood pressure, EMG and perceived exertion. Results from the sustained exertion trials revealed that significant increases in physiological parameters occurred during 3-minute sessions and that this trend was exasperated with deviated wrist posture, particularly flexion. Considering results of both experiments, it was concluded that while the neutral wrist posture may be preferred for a drilling operation, task frequency should be reduced for deviated postures when redesign is not feasible and it is further recommended that deviation be limited to one-third maximum flexion (25 degrees) and two-thirds maximum ulnar deviation (30 degrees). It is also suggested that the psychophysical approach may be utilized to establish 'acceptable' parameters for other industrial tasks involving upper extremity stress, particularly in the current absence of more objective biomechanical and/or physiological criteria for reducing the risk of exposure to cumulative trauma disorders.

The physical work capacity (PWC) and the physiological response to simulated tasks of nine ambulatory individuals with cerebral palsy (CP) were studied. Energy demand for each work task was determined by percentage of PWC (%PWC). Results demonstrated significant differences in energy demand attributed to frequency and mode of lift regardless of gender. No significant difference for energy demand, however, was seen for load lifted. The %PWC for several tasks was near or above the accepted limit for an eight-hour workday, suggesting that the subjects were performing close to their physical limits or higher and would possibly experience fatigue before the eight-hour workday ended. The results also indicated that the PWC of subjects in this study was inferior to that of their nondisabled peers.

An experiment was conducted to assess the differences between various equations and devices for estimating body fat percentage. Valid estimation of body fat is an important variable in determining the individual differences in energy expenditure or physical work capacities of workers performing various tasks. Twenty male volunteers participated in this study. Results indicate that no significant differences exist between device type. However, there were significant differences between derived estimations of body fat content with several widely used equations. These results were also related to estimation of body fat content derived from the bioelectrical impedance procedure. Results from this study indicate the need for comparison between subject population and population of prediction models before determining body fat and possible use of an average of several equations.

Objective measures of anthropometry, strength, range-of-motion, muscle activity, and task performance, and subjective ratings of pain were observed in a group of individuals diagnosed with carpal tunnel syndrome (CTS). These measures were compared to a control population showing no symptoms of CTS. Results indicate that individuals with CTS had significantly lower values on some strength tests, less range of motion on several measures, and reduced performance on a simulated task than did the control group. Ratings of pain and distress for the CTS group were also significantly higher than the control group. Occupational and personality factors associated with the CTS group were also identified and discussed.

This study set out to develop a simple field testing protocol for evaluating the aerobic capacity, forearm isometric strength, and percent body fat of mentally retarded individuals (MRI). A total of 33 (MR) (M IQ=68) subjects (26 males, 7 females) ranging in age from 12 to 49 years participated in this study. A submaximal exercise test using the Schwinn Air-Dyne ergometer was used to estimate aerobic capacity (V̇O2max). Forearm strength was determined by using a hand grip isometric dynamometer. Percent body fat (%BF) was determined by the skinfold method and bioelectrical impedance. All 33 MR subjects who were tested successfully completed the fitness assessment protocol. Correlation coefficients for directly measured versus estimated V̇O2 max and test-retest for forearm strength for 10 of the subjects was .91 and .95, respectively. Slight variations were seen in the methods used to determine %BF. Based on these statistics, it is recommended that the protocol used in this study be considered by those involved in the physical education or training of MRI.

A study was conducted to determine if segment lengths influenced the performance on the sit and reach (SR) test and if the SR test was a valid measure of hamstring and low back flexibility. Thirty-one males and forty-eight females were administered two trials of the SR test using a box as suggested by the AAHPERD's Health Related Fitness Test (1980). Each subject had the height of the acromial, trochanterion, tibial, dactylion, and olecranon measured. A mathematical model was developed to calculate the angle between the legs and the torso (θ). When only the SR test was used to predict θ, there was a coefficient of multiple determination (R 2 = 0.539). However, when torso, total arm (TARM) and total leg (TLEG) lengths were included, the coefficient increased (R 2 = 0.953). This suggest that the SR test is not a good measure of hamstring and low back flexibility for a normal population unless torso, TARM and TLEG lengths are considered. Furthermore, results indicate that segment lengths do have an influence on SR test scores.

This paper presents the results of an anthropometric survey conducted on Korean female workers in the garment industry. The data was collected as part of a project to modify work stations that utilized equipment from other countries. A set of 23 body dimensions were taken from a sample of 101 workers (aged 18-28 years). The anthropometric measurements are presented and compared with those of the Western and Japanese female. The results indicate that the body dimensions of the Korean female are different from those of both the Western and the Japanese female. The ratio of sitting height to standing height for the Korean female is closer to that of the Western female than it is the Japanese female.

A laboratory experiment using 15 male subjects was conducted to document lifting physical work capacity over the frequency range of 2 to 12 lifts per minute and to compare these values to bicycling physical work capacity. Results indicate that bicycling PWC is significantly higher than lifting PWC at the 0.05 level. A variation in lifting PWC as a function of frequency was observed. This could be attributed to lifting technique. Task design should, therefore, not only consider lifting PWC but also the frequency of lift.

This paper presents prediction models based on a study of a combination lift and lower manual handling task that was designed to simulate the loading of grocery bags into a car trunk. Twelve male subjects performed an externally-paced task of lifting plastic grocery bags (with handles) loaded with weights from 15 cm above the floor and over a wooden sill. There were two different sill heights of 70 cm and 90 cm, and for each of these heights there were two frequencies of 3 and 6 lifts per cycle. A unique lifting sequence and a modified version of the psychophysical methodology was used to determine the maximum acceptable weight of lift (MAWOL). Prediction models were determined for MAWOL based upon task, physiological and anthropometric variables as well as a combinations of these. The results indicated that MAWOL could be predicted fairly well.