52,187 research outputs found
Changes in life-style and function in 70-83 year-old subjects participating in a 1-year strength training programme
No full text
Valutazione ergonomica multifattoriale dell'attività infermieristica ospedaliera nell'assistenza ad ammalati non autosufficienti
No full textIndividual profiles of dyspnoea and fatigue on chronic brochitic patients, defined by intensity and duration of submaximal workloads performed
No full textThe subjective perception of fatigue and dyspnoea during submaximal exercise was studied in 10 chronic bronchitic patients using Borg's CR10 scale, with the aim of developing a model for the assessment of sustainable workloads (through the definition of individual perceptual profiles). Each subject performed five trials, consisting of steptests at constant submaximal workloads. Fatigue (CRf) and dyspnoea (CRd) perceptions, heart rate (HR) and duration times were measured. Maximal duration was set at 30 min. The trial was stopped if a fatigue/dyspnoea score of 7 ("very strong") or 85% of the maximum HR was reached. The growth of fatigue and dyspnoea perceptions (R) as functions of time (S) were expressed by the formula: R = a + c (S-b)n. Parameters a, b, c and n calculated for each subject and trial were (mean and SD): a = 0.49 (0.31); b = 2 (0); c = 1.3 (0.61); and n = 0.55 (0.2) for dyspnoea; a = 0.51 (0.27); b = 2 (0); c = 1.4 (0.75); and n = 0.55 (0.2) for fatigue. Individual CR3 "iso-perception" curves (W = k t alpha) for fatigue and dyspnoea in a workload/duration reference system were computed from the experimental data obtained during the five trials. Mean values of the exponent alpha were (.0.5) +/- (-0.23) for dyspnoea, and (-0.41) +/- (-0.22) for fatigue. The CR3 "iso-perception" curves represented the subjectively acceptable level of exertion (defined for load and duration). By doubling the duration and workload, CRd score increments of 1.55 (SD 0.46) and 4.9 (SD 0.42), respectively, were computed. Subjective perceptions are correlated to the intensity and duration of submaximal workload performed, and can be used in conjunction with physiological parameters to predict acceptable workloads in chronic bronchitic patients
TOLERABILITY TO PROLONGED LIFTING TASKS ASSESSED BY SUBJECTIVE PERCEPTION AND PHYSIOLOGICAL-RESPONSES
No full textProlonged physical exertion is regulated subjectively by the perception of effort. This preliminary study was conducted to validate the use of subjective perceptions of effort in assessing objectively tolerable workloads for prolonged lifting tasks. Eight healthy male subjects underwent incremental and 30-minute endurance lifting tests. Cardiorespiratory parameters were monitored with an oxygen uptake analyser and mechanical parameters were calculated using a lift dynamometer. Ratings of perceived exertion were given on Borg's 10-point scale. Physiological responses to repetitive lifting Were matched with subjective perceptions. The relationship between the perception of exertion nd the duration of the endurance tests was descried by power functions; Y = aX(n), in which 0 > n > 1. A single-variable statistical regression for power functions was performed to obtain the individual 'iso-perception' curves as functions of the mechanical work exerted. It was found that the 'iso-perception' curve corresponding to a 'moderate' perception of effort may represent the individual 'tolerance threshold' for prolonged lifting tasks, since physiological responses at this intensity of effort did not change significantly and the respiratory exchange ratio was less than one. The individually tolerable power over time for lifting tasks has been estimated
A field methodology for ergonomic analysis in occupational manual materials handling
No full textA methodology is presented for the 'on-site' evaluation of work-related physical activities, In a first session, video recordings were made of six industrial plant workers during their routine occupational tasks, Heart rate (I-IR) and subjective perception of effort were monitored, The video recordings were then analysed with appropriate software to determine the musculoskeletal load ('Vision 3000', Promatek, Montreal) and to evaluate energy expenditure ('Energy', University of Michigan), The indirect estimates of energy expenditure were validated in a second session by monitoring the six subjects' oxygen consumption (VO2) during the same activities with a portable telemetric oxgen uptake analyser (Cosmed 'K2', Rome). No statistically significant differences were found between direct measurements of (V)over dot O-2 and the computerised estimates of energy expenditure. Biomechanical parameters obtained in the two sessions did not differ, Therefore, we conclude that the 'Energy' programme and the 'Vision 3000' program provide a fast and reliable profile of job requirements. (C) 1997 Elsevier Science Ltd
Long-term strength training for community-dwelling people over 75: impact on muscle function, functional ability and life style
No full textThe objective was to determine the impact of a 1-year mixed strength-training programme on muscle function, functional ability, physical activity and life style. Twice-a-week hospital-based exercise classes and a once-a-week home session were conducted. Nineteen healthy community-dwelling training (7) men (76.6 +/- 3.1 years), 19 women (77.5 +/- 4.0 years) and 20 matched controls (C) participated in this study. Training was given with a two multi-gym machines for the lower limbs (Sitting calf and Leg press, TECHNOGYM, Italy) at 60% of the repetition maximum (1 RM) and at home it was with elastic bands. The following were the measurements made: muscle function-maximum isometric strength of the knee extensors (KE) and ankle plantar flexors (PF) measured with a Cybex Norm dynamometer, leg extensor power (LEP) with the Nottingham Power Rig; functional abilities-functional reach, chair rise, bed rise, 6-min walking test, stair climbing, get up and go, one-leg standing; physical activity-aerobic activities over 3 MET intensity (AA3), intensity classes; life-style-mean daily energy expenditure (MDEE). Significant gains in muscle function and functional abilities in both training females and males were observed, but females improved significantly more than males. Males (T + C) showed higher AA3 times than females (T + C) (P = 0.02), with females significantly more involved in light-intensity activities. We observed a 60% increase (t = 2.45) in AA3 time in T, but no increase in C. Trained males increased Class 2 physical activity time by 146% (t = 2.82) and trained females by 16% (t = 2.23). MDEE increased by 10% (t = 2.62) in trained males. Our long-term mixed programme can improve muscle function and functional abilities in elderly females and functional abilities in males. It can positively affect the amount of habitual physical activity and the life-style of males and females over 75
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