The influence of physical fitness training on the manual material handling capability of women

This study examined the influence of a generalized physical fitness training program on manual material handling (MMH) capability. Thirteen healthy women trained for 14 weeks, performing progressive resistance training three days per week and running with interval training two days per week. Subjects attended 85 ± 6% of the sessions. Compared to values obtained before training, subjects increased the maximum mass they could lift from floor to knuckle height by 19% (68–81 kg, p < 0.001) and from floor to chest height by 16% (49–57 kg, p < 0.001). They improved by 17% their ability to lift 15kg as many times as possible in 10 min(167–195 lifts, p < 0.001), while perception of effort (measured with the Borg Rating of Perceived Exertion) did not change. Total body mass did not change, but body fat mass was reduced by 9% (18.8–17.2 kg, p = 0.036) and fat-free mass increased by 6% (48.2–51.0 kg, p < 0.001). A short-term physical fitness program, conducted about 1 h per day, five days per week, can substantially improve women's MMH capability and provide favorable changes in body composition (increased fat-free mass and decreased body fat).     

Effects of basic training on material handling ability and physical fitness of British Army recruits

No study has yet evaluated the efficacy of British Army basic training in improving material handling performance. Therefore, the purpose of this study was to evaluate the efficacy of the current British Army basic training in improving material handling performance and physical fitness. Forty-seven males (19.4 (3.2)years of age, 1753 (59)mm in height, 71.0 (9.6)kg in weight) and 10 females (21.5 (3.5)years, 1623 (45)mm, 62.5 (5.2)kg) served as subjects. Testing was carried out in the week prior to, and in the final week of, an 11-week basic training course. Maximal box lifts to two different heights, and repetitive lifting and carrying of a 10 kg load did not improve with training. Static (38 cm upright pull) and dynamic (incremental dynamic lift to 145cm) lifting strength data concurred with the maximal box lift data in that no improvement was observed. Repetitive lifting and carrying of a 22kg load improved (29.5%, p&lt;0.001), as did 3.2km loaded march performance with 25 kg (15.7%, p&lt;0.001), but march performance with a 15kg load did not. Predicted VO2 max improved from 48.4 to 51.4 ml.kg-1.min-1, a change of 6.1% (p&lt;0.05). Fat-free mass increased by 0.9 kg (1.5%, p&lt;0.01), and body fat reduced by 2.7% of body mass (20.1%, p&lt;0.001), resulting in a loss of 1.2 kg of body mass (1.7%, p&lt;0.01). It is concluded that basic training in the British Army produces some favourable adaptations in recruits, especially in terms of aerobic fitness. However, the poor development of strength and material handling ability during training fails to improve the ability of soldiers to perform simulated military tasks, and it does little to reduce future injury risk while performing these tasks.     

Effects of basic training on material handling ability and physical fitness of British Army recruits.

No study has yet evaluated the efficacy of British Army basic training in improving material handling performance. Therefore, the purpose of this study was to evaluate the efficacy of the current British Army basic training in improving material handling performance and physical fitness. Forty-seven males (19.4 (3.2) years of age, 1753 (59) mm in height, 71.0 (9.6) kg in weight) and 10 females (21.5 (3.5) years, 1623 (45) mm, 62.5 (5.2) kg) served as subjects. Testing was carried out in the week prior to, and in the final week of, an 11-week basic training course. Maximal box lifts to two different heights, and repetitive lifting and carrying of a 10 kg load did not improve with training. Static (38 cm upright pull) and dynamic (incremental dynamic lift to 145 cm) lifting strength data concurred with the maximal box lift data in that no improvement was observed. Repetitive lifting and carrying of a 22 kg load improved (29.5%, p < 0.001), as did 3.2 km loaded march performance with 25 kg (15.7%, p < 0.001), but march performance with a 15 kg load did not. Predicted VO2max improved from 48.4 to 51.4 ml.kg-1.min-1, a change of 6.1% (p < 0.05). Fat-free mass increased by 0.9 kg (1.5%, p < 0.01), and body fat reduced by 2.7% of body mass (20.1%, p < 0.001), resulting in a loss of 1.2 kg of body mass (1.7%, p < 0.01). It is concluded that basic training in the British Army produces some favourable adaptations in recruits, especially in terms of aerobic fitness. However, the poor development of strength and material handling ability during training fails to improve the ability of soldiers to perform simulated military tasks, and it does little to reduce future injury risk while performing these tasks.     

Effects of intermittent hypoxic training on aerobic and anaerobic performance

The aim of the present study was to determine whether short-term intermittent hypoxic training would enhance sea level aerobic and anaerobic performance over and above that occurring with equivalent sea level training. Over a 4-week period, two groups of eight moderately trained team sports players performed 30 min of cycling exercise three times per week. One group trained in normobaric hypoxia at a simulated altitude of 2750 m (F(I)O2= 0.15), the other group trained in a laboratory under sea level conditions. Each training session consisted of ten 1-min bouts at 80% maximum workload maintained for 2 min (Wmax) during the incremental exercise test at sea level separated by 2-min active recovery at 50% Wmax. Training intensities were increased by 5% after six training sessions and by a further 5% (of original Wmax) after nine sessions. Pre-training assessments of VO(2max), power output at onset of 4 mM blood lactate accumulation (OBLA), Wmax and Wingate anaerobic performance were performed on a cycle ergometer at sea level and repeated 4-7 d following the training intervention. Following training there were significant increases (p < 0.01) in VO(2max) (7.2 vs. 8.0%), Wmax (15.5 vs. 17.8%), OBLA (11.1 vs. 11.9%), mean power (8.0 vs. 6.5%) and peak power (2.9 vs. 9.3%) in both the hypoxic and normoxic groups respectively. There were no significant differences between the increases in any of the above-mentioned performance parameters in either training environment (p > 0.05). In addition, neither haemoglobin concentration nor haematocrit were significantly changed in either group (p > 0.05). It is concluded that acute exposure of moderately trained subjects to normobaric hypoxia during a short-term training programme consisting of moderate- to high-intensity intermittent exercise has no enhanced effect on the degree of improvement in either aerobic or anaerobic performance. These data suggest that if there are any advantages to training in hypoxia for sea level performance, they would not arise from the short-term protocol employed in the present study.     

DEXA-assessed regional body composition changes in young female military soldiers following 12-weeks of periodised training

Dual-energy X-ray absorptiometry (DEXA) was used to assess whole body and regional soft tissue mass, fat mass and lean body mass compositional changes in 68 female recruits (age 20.8 ± 1.14 years; body mass 59.5 ± 8.79 kg; stature 159.57 ± 5.53 cm) pre- and post 12-weeks of military basic training. A decrease in total body fat tissue mass (10.2%) and regional percent fat (10.9%) was measured with an increase in total lean body mass (8.7%). Of interest were the differences in the responses in the tissue composition of the arms (16.2% loss in fat mass with an 11.6% gain in lean mass), trunk (17.0% decrease in fat mass with a 10.4% increase in lean mass) and the legs (10.5% increase in lean mass but no change in fat mass). These findings show the importance of considering regional rather than whole body composition changes when assessing the effects of a training programme.

Statement of Relevance: Female soldiers experienced a change in total body fat tissue (?10.2%) and lean body mass (+8.7%) after basic training; however, no significant fat mass decrease was evident in the leg region. Regional rather than whole body composition changes need to be considered when assessing the effects of a training programme.     

Resistance training and the enhancement of the gains in material-handling ability and physical fitness of British Army recruits during basic training

The aim was to evaluate the efficacy of a modified British Army basic training that included resistance training in improving material-handling performance and physical fitness, and to compare the modified training directly with the normal basic training. Forty-three males [19.2 (2.6) years of age, 1764 (72) mm in height, 73.0 (10.6) kg in mass] and nine females [19.1 (2.2) years, 1641 (67) mm, 62.0 (7.2) kg] performed the modified basic training. Testing occurred in the week before and in the final week of the 11-week basic training. Improvements with the modified training were observed for all six material-handling tests, including 8–12% for maximal box lifting, 15–19% for repetitive lifting and carrying and 9–17% for loaded marching (all p <0.01), and other established measures of aerobic fitness, strength and kinanthropometric characteristics. Significantly greater improvements were observed for the modified training compared with the normal training in maximal box lift to 1.45 m (12.4 versus 1.7%, p <0.01), 3.2 km loaded march performance with 15 kg (8.9 versus 3.6%, p <0.05), estimated fat-free mass (4.2 versus 1.5%, p <0.001), predicted [Vdot]O_2max (1 min ^-1) (9.3 versus 4.1%, p <0.01) and dynamic lift to 1.45 m (15.5 versus 0.2%, p <0.001). It was concluded that the improvements in material-handling ability and other aspects of physical fitness brought about in recruits by British Army basic training can be enhanced by the use of a physical training programme that includes a carefully designed resistance training element. Of particular note are the improvements shown in performance on material-handling tasks that require muscular strength, as these represent many of the tasks that soldiers encounter in their military careers.     

Resistance training and the enhancement of the gains in material-handling ability and physical fitness of British Army recruits during basic training

The aim was to evaluate the efficacy of a modified British Army basic training that included resistance training in improving material-handling performance and physical fitness, and to compare the modified training directly with the normal basic training. Forty-three males [19.2 (2.6) years of age, 1764 (72) mm in height, 73.0 (10.6) kg in mass] and nine females [19.1 (2.2) years, 1641 (67) mm, 62.0 (7.2) kg] performed the modified basic training. Testing occurred in the week before and in the final week of the 11-week basic training. Improvements with the modified training were observed for all six material-handling tests, including 8-12% for maximal box lifting, 15-19% for repetitive lifting and carrying and 9-17% for loaded marching (all p < 0.01), and other established measures of aerobic fitness, strength and kinanthropometric characteristics. Significantly greater improvements were observed for the modified training compared with the normal training in maximal box lift to 1.45 m (12.4 versus 1.7%, p < 0.01), 3.2 km loaded march performance with 15 kg (8.9 versus 3.6%, p < 0.05), estimated fat-free mass (4.2 versus 1.5%, p < 0.001), predicted VO(2max) (1 min(-1)) (9.3 versus 4.1%, p < 0.01) and dynamic lift to 1.45 m (15.5 versus 0.2%, p < 0.001). It was concluded that the improvements in material-handling ability and other aspects of physical fitness brought about in recruits by British Army basic training can be enhanced by the use of a physical training programme that includes a carefully designed resistance training element. Of particular note are the improvements shown in performance on material-handling tasks that require muscular strength, as these represent many of the tasks that soldiers encounter in their military careers.     

基于煤矿井下UWB脉冲产生电路的设计与研究

介绍了我国煤矿矿井无线通信的现状,提出将超宽带无线通信技术应用于井下。针对UWB脉冲的幅频特性,详细分析了晶体管雪崩效应理论和工作原理,利用此方法设计出多级并联同触发窄脉冲发生电路,提高了脉冲的幅值,降低了脉冲的时延和宽度,并通过仿真得以实现。此电路工作稳定,可靠性高,通过对电路参数修正,可适应不同的通信领域。     

Little effect of transfer technique instruction and physical fitness training in reducing low back pain among nurses: a cluster randomised intervention study

The aim of this study was to evaluate the effect of a transfer technique education programme (TT) alone or in combination with physical fitness training (TTPT) compared with a control group, who followed their usual routine. Eleven clinical hospital wards were cluster randomised to either intervention (six wards) or to control (five wards). The intervention cluster was individually randomised to TT (55 nurses) and TTPT (50 nurses), control (76 nurses). The transfer technique programme was a 4-d course of train-the-trainers to teach transfer technique to their colleagues. The physical training consisted of supervised physical fitness training 1 h twice per week for 8 weeks. Implementing transfer technique alone or in combination with physical fitness training among a hospital nursing staff did not, when compared to a control group, show any statistical differences according to self-reported low back pain (LBP), pain level, disability and sick leave at a 12-month follow-up. However, the individual randomised intervention subgroup (transfer technique/physical training) significantly improved the LBP-disability (p = 0.001). Although weakened by a high withdrawal rate, teaching transfer technique to nurses in a hospital setting needs to be thoroughly considered. Other priorities such as physical training may be taken into consideration. The current study supports the findings of other studies that introducing transfer technique alone has no effect in targeting LBP. However, physical training seems to have an influence in minimising the LBP consequences and may be important in the discussion of how to prevent LBP or the recurrence of LBP among nursing personnel.     

Little effect of transfer technique instruction and physical fitness training in reducing low back pain among nurses: a cluster randomised intervention study

The aim of this study was to evaluate the effect of a transfer technique education programme (TT) alone or in combination with physical fitness training (TTPT) compared with a control group, who followed their usual routine. Eleven clinical hospital wards were cluster randomised to either intervention (six wards) or to control (five wards). The intervention cluster was individually randomised to TT (55 nurses) and TTPT (50 nurses), control (76 nurses). The transfer technique programme was a 4-d course of train-the-trainers to teach transfer technique to their colleagues. The physical training consisted of supervised physical fitness training 1 h twice per week for 8 weeks. Implementing transfer technique alone or in combination with physical fitness training among a hospital nursing staff did not, when compared to a control group, show any statistical differences according to self-reported low back pain (LBP), pain level, disability and sick leave at a 12-month follow-up. However, the individual randomised intervention subgroup (transfer technique/physical training) significantly improved the LBP-disability (p = 0.001). Although weakened by a high withdrawal rate, teaching transfer technique to nurses in a hospital setting needs to be thoroughly considered. Other priorities such as physical training may be taken into consideration. The current study supports the findings of other studies that introducing transfer technique alone has no effect in targeting LBP. However, physical training seems to have an influence in minimising the LBP consequences and may be important in the discussion of how to prevent LBP or the recurrence of LBP among nursing personnel.     

Effects of respirators on performance of physical, psychomotor and cognitive tasks

Possible work decrements caused by respirator usage were examined. A battery of physical, psychomotor and cognitive tasks was used to investigate the effects of respirator wear on 12 subjects. A repeated measures experimental design was used to study the effects of three types of respirators: a disposable dust mask; an air purifying half-mask; and a full-face airline mask. Performance while wearing a mask was compared to the control condition without a respirator. The results from the physical work task of riding a bicycle ergometer indicated approximately a 10% increase in oxygen consumption when subjects wore half and full-face masks in comparison to when they performed the tasks without a mask. The results indicate that wearing the respirators did not have a significant effect on the performance of cognitive tasks but did affect significantly the performance of psychomotor tasks such as steadiness of work performance and movements requiring accurate control for positioning of objects.     

Effects of weight balance on a 3D TV shutter type glasses: Subjective discomfort and physical contact load on the nose

A two-phase experimental study examined the effects of weight balance in 3D TV shutter type glasses by subjective discomfort and physical contact load on the nose. Four 3D glasses with different weight-concentrated locations (Front, Middle, Ear, and Rear) and one Reference glasses were investigated. Subjective discomfort ratings on the overall, nose, and posterior edge of the ear were obtained using a 100 point visual analogue scale, and physical load on the nose was measured by force sensing resistor (FSR) film sensors. The overall and nose discomforts for Front were significantly higher than other conditions; the ear discomfort for Ear was significantly worse than the others. The nose load for Front (0.34 N) was significantly higher than Middle (0.22 N), Ear (0.20 N), Rear (0.16 N), and Reference (<0.05 N). A correlation analysis presented that the overall and nose discomforts were closely related (r > 0.9) to the nose load.Relevance to IndustryEffects of weight balance in 3D TV shutter type glasses were examined in terms of subjective discomfort and physical nose load. Overall discomfort and physical nose load significantly declined while the weigh-concentrated location moved from the front to the rear of temples.     

The effect of physical training on objective and subjective measures of productivity and efficiency in industry

The aims of this study were to investigate the associations between an activity logbook and the RT3 accelerometer and to assess whether the RT3 can discriminate activity levels in healthy adults. Ten participants completed two trials wearing an RT3 accelerometer over a 4–6 h period and completed a detailed activity log. Results showed a poor correlation between the RT3 in moderate activities (r = 0.22) in comparison to low (r = 0.52) and hard (r = 0.70) from the logbook. A significant difference was found in average RT3 vector magnitude (VM) counts/min in each activity level (p < 0.0001). Discriminant analysis demonstrated that an RT3VM counts/min value of approximately 500 was found to have high sensitivity (88%), and specificity (88%) for discriminating between low and moderate activity levels from the logbook. This study found that accelerometry has the potential to discriminate activity levels in free living. This study is the first to investigate whether tri-axial accelerometry can discriminate different levels of free-living activity recorded in an activity logbook. The RT3 accelerometer can discriminate between low and moderate physical activities and offers a methodology that may be applicable to future research in occupational settings.     

Effects of high pixel density on reading comprehension,proofreading performance,mood state,and physical discomfort

Displays with low pixel densities that were common in the 1980s and 1990s were shown to impair visual performance. Display technology, especially pixel density, has tremendously improved in recent years and new technologies allow densities of 264 ppi and beyond. Two experiments were conducted to test whether there are any measurable benefits of high pixel density displays (264 ppi) over moderate pixel density displays (132 ppi). In Experiment 1, participants performed a reading comprehension task on a display with either high or low pixel density. In Experiment 2, participants’ speed and performance in a proofreading task were compared using the same displays with high and low pixel density. There were no differences in reading comprehension and reading time (Experiment 1) as well as proofreading speed and performance (Experiment 2) between a 132 ppi and a 264 ppi display. However, subjective ratings of physical discomfort revealed significantly more complaints about headache and musculoskeletal strain in the 132 ppi condition than in the 264 ppi condition (Experiment 2). Reading comprehension, reading speed, and proofreading performance are unaffected by pixel densities above 132 ppi, but reading from high-resolution screens seems to be less exhausting at least subjectively. Thus, while large performance differences cannot be expected, displays with high pixel densities (264 ppi and above) have some advantage over displays with moderate (132 ppi or lower) pixel densities.     

The composition of a graph on the decline of total body strength with age based on pushing, pulling, twisting and gripping force

This study is part of a large project on design-relevant characteristics of ageing users. A total of 750 young and elderly, male and female subjects were tested. All subjects were able to live independently. Differences between the sexes were mapped as well as changes in force with age. The relationships between five different isometric forces (pushing, pulling, twisting and left and right gripping) were investigated. The possibilities of extending information on these forces to other forces and other subject groups were also studied. The results indicate that the different types of force are closely related. A strength score was devised. We conclude that calculation of unmeasured forces by means of a general strength score could be possible. Furthermore, we found that the percentage decrease in strength with age is similar for men and women.     

Effects of physical exertion on task performance in modern manufacturing: a taxonomy,a review,and a model

Modern manufacturing systems have the characteristic of demanding human cognitive task performance in an environment where sudden physical demands are also possible. There is little research addressing the effects of physical work on cognitive task performance and it is not well organized for application to manufacturing systems design. This paper uses an initial three-dimensional taxonomy to review the literature. Some clear findings emerge, but many studies produced contradictory results. While part of this contradiction was due to experimental technique, some was also due to the lack of a detailed structure to guide future research. Such a model is thus proposed, using the concept of limited resources for both the cognitive and physical aspects of tasks. In addition, specific predictions of research needs for modern manufacturing systems arise.     

Effects of box weight,vertical location and symmetry on lifting capacities and ratings on category scale in Japanese female workers

The aim was to clarify the effects of box weight, vertical location and symmetry on the lifting capacities and subjective burden in Japanese female workers with manual material handling tasks. Sixteen healthy females were tested. They performed 12 different lifting tasks (three heights * two weights * two symmetries). It is difficult for Japanese women to exert dynamic force in lifting a 15-kg weight from the elbow to the shoulder level. A remarkable increase was observed in heart rate and category scale with ratio properties (CR-10) on large muscle group in lifting a 15-kg weight as compared with lifting a 10-kg one. Judging from calculation of the Recommended Weight Limit using the application manual by the National Institute for Occupational Safe and Health, it was also suggested that lifting the 15-kg weight from the elbow to the shoulder level was difficult for female workers. Not only peak force, but also the average upward acceleration and peak velocity were lower in asymmetric liftings than those in symmetric liftings. CR-10 for the left back and right thigh were also higher in 90° right lateral plane lifting than in the mid-sagittal plane. Thus, asymmetric lifting was supposed to impose higher stress on the back contralaterally and thigh ipsilaterally to the location of the weight.