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Biomedical subjects

A Mital

Publications and source records attributed to A Mital.

63 records · Page 4Linked to original sources
PubMed1981

Effect of task variables and their interactions in lifting and lowering loads.

An experiment was designed to study the effect of several task variables on the metabolic energy expenditure and heart rate of individuals performing lifting and lowering tasks. The task variables studied were: load of lift (lower), frequency of lift (lower), height of lift (lower), presence of absence of handles, container height, container width (in the frontal plane) and container length (in the sagittal plane). Four male subjects participated in the experiment. Their oxygen uptake and heart rate were monitored. Various strength measurements were made on the subjects before their participation in the study and after the study was over. The data were analyzed separately for lifting and lowering, using the analysis of variance. Container height did not affect the metabolic energy expenditure or heart rate of the subjects for lifting or lowering activities. Presence or absence of handles did not cause a significant change (alpha greater than or equal to .10) in the physiological responses for lowering tasks. All other task variable effects, however, were significant (alpha less than or equal to .01). A strong first and second order interaction was observed among the task variables. There was a significant increase in the strength (alpha less than or equal to .025) of subjects after performing manual materials handling activities for about seven weeks. A dimensional sensitivity analysis indicated that unit change in box width was more expensive than unit change in box length up to .56 m (22 inches). Beyond this, unit change in box length became critical. The weight/bulk ratio of the object did not affect the physiological responses.

Adolescent↗
PubMedDate not supplied

Psychophysical capacity of industrial workers for lifting symmetrical and asymmetrical loads symmetrically and asymmetrically for 8 h work shifts.

This paper presents comprehensive maximum acceptable weight of lift (psychophysical lifting capacity) database for male and female industrial workers for lifting symmetrical and asymmetrical loads symmetrically and asymmetrically for 8 h work shifts. The experimental data collected in previous studies on experienced (industrial) and inexperienced (non-industrial) materials handlers (Mital 1984a, Mital and Fard 1986) and the patterns of responses between the two populations (Mital 1985, 1987) were used to generate this database. Since previous work (Mital 1985, 1987) showed that responses of both experienced and inexperienced materials handlers to task variables are similar and also provided multipliers relating the psychophysical lifting capacities of the two populations, it was possible: (1) to convert psychophysical capacity data for asymmetrical lifting of symmetrical and asymmetrical loads, collected on inexperienced workers to reflect psychophysical lifting capacity of experienced workers for asymmetrical lifting; and (2) to take psychophysical lifting capacity data of experienced industrial workers for symmetrical lifting of symmetrical loads and generate from it their psychophysical lifting capacity for symmetrical and asymmetrical lifting of symmetrical and asymmetrical loads by using the response patterns of inexperienced workers to lifting symmetrical and asymmetrical loads symmetrically and asymmetrically. Both approaches were used and, as expected, provided almost identical values for the psychophysical lifting capacity of industrial workers for symmetrical and asymmetrical lifting of symmetrical and asymmetrical loads. Therefore, the final database tables provided in this paper used combined values generated by the two methods.

Databases, Bibliographic↗
PubMedDate not supplied

Margin of safety for the human back: a probable consensus based on published studies.

Despite numerous efforts to control occurrences of work-related low back pain, it continues to be a significant problem. Since the causation of low back pain is under multifactorial control, it is suggested that the factor most vulnerable at any given time will determine the safety. Epidemiological, biomechanical, physiological, and psychophysical information presented in published literature has been analysed. The data available are related to injuries and the projected margin of safety. This paper therefore, is an integrative, inferential synthesis of the published work to discern the margin of safety. An attempt has been made to conclude, on the basis of objective evidence, an all encompassing criterion to ensure the safety of the back. The psychophysical approach appears to integrate biomechanical and physiological variables on a short term basis in the studies surveyed. However, it remains to be proven that the sensory conditioning due to prolonged and repetitive occupational tasks will remain responsive to cumulative load and fatigue failures.

Humans↗
PubMedDate not supplied

Reach profiles of men and women 65 to 89 years of age.

Reach and anthropometric data were collected on a heterogeneous group of subjects 65 to 89 years of age. The purpose of this pilot study was to determine whether the process of aging has an effect on the ability to reach. Analysis of the data collected showed that age-related changes had an effect on reaching in the vertical plane, especially for the male subjects. The vertical reach fingertip and grip (VRT and VRG) measurements for men 85 to 89 years old were significantly lower than those for all other age groups, indicating that reaching abilities decrease between the ages of 80 and 85 years. The results for women were not as conclusive, but additional analysis showed a decline in VRT and VRG in terms of stature. Horizontal reach measurements showed no age-related effect in the analysis. An attempt was made to compare reach data collected here with those collected in previous studies. However, comparisons of the reach data were limited as a result of differences in reaching activities and measuring techniques in other studies. Anthropometric measurements of this older cohort were compared with those of a younger population. It was noted that older subjects had smaller anthropometric measurements than their younger cohorts. Differences in body size and reach, whether statistically significant or not, need to be considered when designing living environments and appliances for the aged.

Aged↗
PubMedDate not supplied

Accelerating the return to work (RTW) chances of coronary heart disease (CHD) patients: part 1--development and validation of a training programme.

PURPOSE: Conventional phase II cardiac rehabilitation (CR) programmes have not resulted in an improvement in returning coronary heart disease (CHD) patients to work in over 35 years. This 4 year field-initiated research, sponsored by the National Institute on Disability and Rehabilitation Research, compares conventional CR programmes with a low-intensity CR programme that simulates elements of work (job-simulated CR programme) in terms of return to work (RTW) and physiological conditioning. The effect of training on physical capabilities of patients participating in the job-simulated CR programme was also of equal interest. METHOD: Thirty patients (15 bypass and 15 angioplasty; 15 males and 15 females) participated in a conventional CR programme (control group). The job-simulated CR programme included 15 male and 2 female bypass and angioplasty patients (experimental group). Patients in the control group underwent regular aerobic exercise training (treadmill and bicycle). Experimental group patients participated in a series of low-intensity exercises such as progressive time exercises, flexibility exercises, and dexterity exercises. RESULTS: All patients participating in the low-intensity job-simulated CR programme returned to the same job they held at the onset of myocardial infarction (MI). In contrast, only 60% of the control group patients returned to work; at least one-third of these did not go back to the same job they held at the onset of M1. Patients in both groups achieved the same level of physiological conditioning. The physical functional capabilities of the experimental group patients improved significantly throughout training. CONCLUSION: The results of this field-study lead to the conclusion that a low-intensity phase II cardiac rehabilitation programme that simulates elements of work may be far superior to conventional endurance exercise-based cardiac rehabilitation programmes in terms of returning patients to work. Such a programme also strengthens patients, improving their physical capabilities, without compromising their physiological conditioning.

Adult↗
PubMedDate not supplied

Accelerating the return to work (RTW) chances of coronary heart disease (CHD) patients: part 2--development and validation of a vocational rehabilitation programme.

PURPOSE: This paper, part 2 of the two-part paper, reviews return-to-work outcomes among individuals with coronary heart disease, who participated in an experimental field study reported in part 1 of the two-part paper. Study results reflected specific job stressors associated with physical and mental demands among various job tasks. Trends suggest that personality characteristics commonly associated with 'type a' personalities and cardiac disease risk factors may also serve as positive forces that influence return-to-work activity. METHODS/RESULTS: Relatively high levels of job satisfaction were reported among most experimental subjects. Despite having high return-to-work expectations, these patients lacked specific strategies and resources to facilitate a concrete return to work action plan. CONCLUSION: The researchers conclude that it is essential for cardiac rehabilitation staff, when creating a return to work transition for their cardiac patients, to explore the physical and psychosocial dimensions of jobs, the receptivity of the employer, and the accommodations needed to promote a safe and timely return to work.

Adult↗