Non-experienced Subjects Research Articles

The Relationship of Trunk Muscle Activation and Core Stability: A Biomechanical Analysis of Pilates-Based Stabilization Exercise.

Pilates is an effective exercise method for rehabilitating musculoskeletal disorders as its principles are based on the activation of local muscles. This study aimed to compare the subjects with and without Pilates experience to find out the effect of the experience on the core muscle activity and muscle co-contraction, and to examine the relationship between the core muscle activation level and the kinematic data. This study involved 32 subjects, including 16 experienced Pilates practitioners and 16 non-experienced subjects. The knee stretch on the reformer was performed in three different positions: flat back with a neutral pelvis, round back with posteriorly tilted pelvis (RPP), and extended back anteriorly tilted pelvis (EAP). The electromyography of the internal oblique (IO), rectus abdominis (RA), multifidus (MU), and iliocostalis lumborum (IL) muscles were measured, as well as kinematic data from a 3D motion analysis system. Compared to the non-experienced subjects, the experienced subjects activated the IO muscles more than the RA muscles, and the most significant difference was seen in the RPP position (p < 0.05). The experienced patients activated the MU muscles more often than the IL muscles, with the most significant difference observed in the RPP position and the least significant in the EAP position (p < 0.05). All kinematic data and muscle activity (IO, IO/RA ratio, MU/IL ratio) showed significant differences between the experienced and non-experienced subjects (p < 0.05). The subjects presented a moderate correlation between muscle activation and core stability. It was confirmed that the experienced Pilates practitioners activated the abdominal and low back core muscles effectively, and the stability of the pelvis and trunk were better than that of the non-experienced participants. In addition, the better the trunk stability was maintained, the larger and more accurate movement of the mobility segment was observed.

Pick-place of dynamic objects by robot manipulator based on deep learning and easy user interface teaching systems

PurposeDevelopment of autonomous robot manipulator for human-robot assembly tasks is a key component to reach high effectiveness. In such tasks, the robot real-time object recognition is crucial. In addition, the need for simple and safe teaching techniques need to be considered, because: small size robot manipulators’ presence in everyday life environments is increasing requiring non-expert operators to teach the robot; and in small size applications, the operator has to teach several different motions in a short time.Design/methodology/approachFor object recognition, the authors propose a deep belief neural network (DBNN)-based approach. The captured camera image is used as the input of the DBNN. The DBNN extracts the object features in the intermediate layers. In addition, the authors developed three teaching systems which utilize iPhone; haptic; and Kinect devices.FindingsThe object recognition by DBNN is robust for real-time applications. The robot picks up the object required by the user and places it in the target location. Three developed teaching systems are easy to use by non-experienced subjects, and they show different performance in terms of time to complete the task and accuracy.Practical implicationsThe proposed method can ease the use of robot manipulators helping non-experienced users completing different assembly tasks.Originality/valueThis work applies DBNN for object recognition and three intuitive systems for teaching robot manipulators.

Teaching Industrial Robot Manipulators by Easy to Use Interface Systems

The need for simple and safe teaching methods for robot manipulators need to be considered because: 1) Small size robots presence in everyday life environments is increasing requiring non-experts operators to teach the robot; 2) In small applications, the operator has to teach several different motions in a short time. In this paper, we evaluate the performance of three teaching systems for robot manipulators which utilize the following devices 1) i-phone; 2) haptic and 3) kinect. In difference from previous force sensor based teaching, proposed systems are safe because the operator keeps the distance with the robot. The performance is compared in terms of time to complete the task and accuracy. The results of 10 non-experienced subjects show the advantages of one method over the others.

The comparative effects between demonstration video and instruction manual on the performance for respiratory protective device

BackgroundRespiratory Protective Device has been used in non-residential areas such as hotels and offices. It is impossible to demonstrate how to use the safety device for all users. Many hotels...

Mountaineering experience decreases the net oxygen cost of climbing Mont Blanc (4,808 m)

The purpose of this study was to test the hypothesis that mountaineering experience decreases the net oxygen cost of uphill walking (OCw) on steep mountain trails and in ice and snow conditions. OCw was measured during an ascent of Mont Blanc in eight experienced alpinists and eight non-alpinists who were matched for sex (4 + 4) and low-altitude aerobic power (V(O)(2)(max) 50-55 ml kg(-1) min(-1)). Subjects carried a breath-by-breath gas exchange analyzer and a GPS. V(O)(2)(max) at altitude was estimated from measured low-altitude V(O)(2)(max) using Bassett's equation to calculate fractional use of V(O)(2)(max) during the ascent (FV(O)(2)(max)). OCw was calculated as the difference between V(O)(2) while climbing minus resting V(O)(2). At all elevations, Alpinists exhibited a lower OCw (P < 0.01). In all subjects, OCw increased when encountering ice and snow conditions. FV(O)(2)(max) remained stable around 75% at all elevations independent of experience or sex. In conclusion, the OCw is lower in experienced mountaineers compared to non-experienced subjects, and increases when going from steep rocky mountain terrain to ice and snow conditions, independent of mountaineering experience or sex.

The Effect Of Climbing Experience On Metabolic Responses To Graded Exercise Tests Performed On A "Treadwall", Treadmill, And Cycle Ergometer

Evidence suggests that subjects will achieve an ∼16% lower VO2 during a GXT performed on a cycle ergometer (CE) and a vertical treadmill {treadwall (TW)} as compared to a treadmill (TM). However, there appears to be no data comparing the same parameters between experienced (Ex) and nonexperienced (NEx) climbers. PURPOSE: To compare metabolic data between Ex and NEx subjects that performed GXT's on a TM, CE, and a TW. METHODS: NEx {n=22 (11 males & 11 females); 24.0 ± 3.5yrs; 170.8 ± 12.4cm; 69.7 ± 14.0kg; 19.1 ± 7.5%bf} and Ex {n=8 (7 males & 1 female); 28.0 ± 8.7yrs; 175.8 ± 5.4cm; 67.9 ± 10.3kg; 8.6 ± 4.6%bf} subjects were tested on the different ergometers on separate days to determine their highest achievable VO2 (order counterbalanced). VO2, respiratory exchange ratio (RER), and heart rate (HR) were measured, along with several metabolic parameters. RESULTS: A significant difference (p<0.05) was found between groups (Ex vs. NEx) for VO2 on the TM, CE, and TW, but not for RER or HR on any ergometer. With Ex and NEx grouped separately, a significant main effect was found between all ergometers for VO2, RER, and HR. A significant difference was found for VO2 between TM (Ex = 52.1 + 6.0; NEx = 42.9 + 4.6) and CE (Ex = 48.0 + 4.4; NEx = 35.9 + 4.9) and between TM and TW (Ex = 45.3 + 6.1; NEx = 36.2 + 4.1) in both the Ex and NEx groups. There was also a significant difference found for RER between TM (Ex = 1.11 + 0.08; NEx = 1.10 + 0.04) and CE (Ex = 1.19 + 0.08; NEx = 1.19 + 0.06), between TM and TW (Ex = 1.01 + 0.05; NEx = 1.05 + 0.06), and between CE and TW in both the Ex and NEx groups. Lastly, a significant difference was found for HR between TM (195.1 + 7.2) and CE (183.3 + 10.1) and between TM and TW (180.6 + 7.7) in the NEx group. However, in the Ex group the only significant difference found for HR was between TM (186.6 + 15.9) and TW (175.8 + 17.7). CONCLUSION: There was found to be a 7.9% difference between TM and CE for VO2 in Ex. However, the difference in VO2 between TM and CE was 16.3% in NEx. The percentage difference for VO2 was more similar for the Ex and NEx groups between TM and TW (13.1% and 15.6% respectively), which suggests regardless of climbing experience subjects performing a GXT on a TW will hit a ceiling in VO2 at approximately the same point relative to their aerobic fitness.

Initial validation of a virtual-reality robotic simulator.

Robotic surgery is an accepted adjunct to minimally invasive surgery, but training is restricted to console time. Virtual-reality (VR) simulation has been shown to be effective for laparoscopic training and so we seek to validate a novel VR robotic simulator. The American Urological Association (AUA) Office of Education approved this study. Subjects enrolled in a robotics training course at the 2007 AUA annual meeting underwent skills training in a daVinci dry-lab module and a virtual-reality robotics module which included a three-dimensional (3D) VR robotic simulator. Demographic and acceptability data were obtained, and performance metrics from the simulator were compared between experienced and nonexperienced roboticists for a ring transfer task. Fifteen subjects-four with previous robotic surgery experience and 11 without-participated. Nine subjects were still in urology training and nearly half of the group had reported playing video games. Overall performance of the daVinci system and the simulator were deemed acceptable by a Likert scale (0-6) rating of 5.23 versus 4.69, respectively. Experienced subjects outperformed nonexperienced subjects on the simulator on three metrics: total task time (96s versus 159s, P<0.02), economy of motion (1,301mm versus 2,095mm, P<0.04), and time the telemanipulators spent outside of the center of the platform's workspace (4s versus 35s, P<0.02). This is the first demonstration of face and construct validity of a virtual-reality robotic simulator. Further studies assessing predictive validity are ultimately required to support incorporation of VR robotic simulation into training curricula.

Assessment of the ergonomic design of diagnostic ultrasound transducers through wrist movements and subjective evaluation

Abstract This study presents procedures for assessing the redesign of ultrasound transducers. Wrist movements were recorded using electrogoniometers. Perceptions of discomfort and acceptability of the new transducers were evaluated. The assessment was performed in two phases: (1) design of the product and an initial evaluation of movements during simulated activity with one mock-up and with two commercially available transducers; (2) project review and the development and evaluation of new mock-ups (2 and 3) by non-experienced subjects, and subjective assessment of all the mock-ups and commercial transducers by non-experienced subjects and trained physicians. First mock-up did not present improvements regarding the wrist movements and the time spent within safe amplitudes. The project review resulted in two new mock-ups that led to lower average amplitudes of movements ( p ⩽0.05) and more time spent within safe amplitudes. Thus, the application of quantitative (recording movements) and subjective (perceptions of discomfort and acceptability) approaches allowed for subsequent redesigns of the transducers that led to improvement of the product under evaluation. Relevance to Industry Systematic assessment methodology can be used for safer and more comfortable products. New designs of diagnostic ultrasound transducers are proposed in this study.

Body Physique and Prior Training Experience as Determinants of SEFIP Score for University Dancers

The Self-Estimated Functional Inability because of Pain (SEFIP) questionnaire is a simple tool used to define the pain status in different body regions of performers in aesthetic sports. In this study we revalidated the SEFIP in a sample of nonprofessional female university dancers (n = 45; mean age, 22.3 yrs). The dancers were divided into two groups according to their previous experience in dance and aesthetic-based sports: experienced (n = 24) and nonexperienced (n = 21). SEFIP was measured before and after the 6-week dance and aesthetic-based training program. Morphologic variables were measured at study entry and included body weight, height, body mass index (BMI), calf circumference, sum of two skinfolds, and percent body fat. We analyzed 1) the differences between experienced and nonexperienced dancers in all variables, 2) pre- and post-training differences in SEFIP, 3) pre- and post-training differences in pain sensation for each body region, and 4) the prediction of the SEFIP score from morphologic variables in the experienced and nonexperienced subjects. Statistical analysis using the t-test found no significant differences between the groups but identified significant pre- vs. post-training differences in SEFIP in the sample taken as a whole. The nonparametric sign test showed a significant pre- to post-training decrease in pain sensation in the calf region. Multiple regression analysis revealed BMI as a significant predictor of the SEFIP, but only for the nonexperienced dancers. In order to avoid pain occurrence in university dancers, previous training of the calf, thigh, and back muscles is suggested, especially in those subjects with BMI &gt; 21 kg/m2.

Evaluating Tactile Sensitivity Adaptation by Measuring the Differential Threshold of Archers

This study investigated the relationship between the force applied to a finger and the differential threshold of the force. Further, it presented an improvement function for tactile perception in archers by adapting to circumstances in which enhanced tactile perception and finger dexterity are required to practice archery on a daily basis. For this purpose, a tactile display using an air jet was developed. The air was aimed at the center of the fingertip of the index finger. The inner diameter of the nozzle was set to 3 mm. In this study, a psychophysical experiment was conducted to obtain the differential threshold from two subject groups-an archery athlete group and a control group. A total of six levels of standard stimuli ranging from 2.0 gf to 7.0 gf was obtained. As a result, the differential threshold of the archery group was significantly higher than that of the control group. The Weber ratio of the archery group remained around 0.13 and that of control group was 0.10. The experiment also revealed that the differential threshold for archers exhibited less fluctuation between the trials and between the days, which implied that the tactile perception of archery athletes may be more stable than that of non-experienced subjects. This may be a plasticity property of tactile perception.

Biomechanics of Rowing. I. A Model Analysis of Musculo-Skeletal Loads in Rowing for Fitness.

Compared with the other exercise, such as walking and cycling, rowing was expected to have some fitness advantage, while there were some misgivings about the risk of injury. The objectives of this study were to quantify biomechanical characteristics of rowing for fitness and rehabilitation and to offer normative data for the prevention of injury and for determining effective exercise. An experiment was performed to collect the kinematic and kinetic data during rowing by experienced and non-experienced subjects. A three-dimensional whole-body musculo-skeletal model was used to calculate the biomechanical loads, such as the joint moments, the muscular tensions, the joint contact forces and the energy consumption. The results of this study indicate that rowing is an effective exercise for rehabilitation and fitness. However, the non-experienced rower should acquire considerable skill to obtain sufficient exercise. The rowing cadence should be decided according to the purpose of the exercise.

Focusing of Visuospatial Attention

Abstract In the present study we explored the focusing of visuospatial attention in subjects practicing and not practicing activities with high attentional demands. Similar to the studies of Castiello and Umiltà (e. g., 1990) , our experimental procedure was a variation of Posner's (1980) basic paradigm for exploring covert orienting of visuospatial attention. In a simple RT-task, a peripheral cue of varying size was presented unilaterally or bilaterally from a central fixation point and followed by a target at different stimulus-onset-asynchronies (SOAs). The target could occur validly inside the cue or invalidly outside the cue with varying spatial relation to its boundary. Event-related brain potentials (ERPs) and reaction times (RTs) were recorded to target stimuli under the different task conditions. RT and ERP findings showed converging aspects as well as dissociations. Electrophysiological results revealed an amplitude modulation of the ERPs in the early and late Nd time interval at both anterior and posterior scalp sites, which seems to be related to the effects of peripheral informative cues as well as to the attentional expertise. Results were: (1) shorter latency effects confirm the positive-going amplitude enhancement elicited by unilateral peripheral cues and strengthen the criticism against the neutrality of spatially nonpredictive peripheral cueing of all possible target locations which is often presumed in behavioral studies. (2) Longer latency effects show that subjects with attentional expertise modulate the distribution of the attentional resources in the visual space differently than nonexperienced subjects. Skilled practice may lead to minimizing attentional costs by automatizing the use of a span of attention that is adapted to the most frequent task demands and endogenously increases the allocation of resources to cope with less usual attending conditions.

EFFECT OF TWO NEAR MAXIMUM LIFTS COMPARED TO EIGHT LIFTS IN RELATION TO STRENGTH DEVELOPMENT

The purpose of this study was to determine if a new – and less time consuming – dynamic weight lifting method could be used to produce skeletal muscle strength and hypertrophy. The new weight lifting program consisted of doing three sets of two repetitions at 90 percent of 1RM maximum. A traditional eight-repetition program consisting of three sets done at 65 percent, 70 percent and 75 percent respectfully, of a 1RM maximum was used as a constant to compare against. Eighteen subjects, ranging from 18 to 25 years of age and free of any injuries took part in the study. Subjects' experience in weight lifting ranged from novice to two years. All subjects completed a predetermined four-week pre-conditioning program before being placed into one of two eight-week groups (either the two-repetition group or the eight-repetition group.) During the eight-week test period, subjects exercised twice a week with twelve different weight lifting exercises using the percentage of weight and repetitions assigned to their group. Four separate examinations were conducted during the study to gauge changes in percentage of body fat, body weight, body girths and strength. Strength was gauged using a 1RM maximum test for eight different weight lifting exercises. The data revealed that both groups experienced measurable gains in strength. There was no significant difference between the two groups, or between the experienced and non-experienced subjects in strength gains. No significant changes occurred to body composition except that percentage of fat went down for both groups. This study showed that a two-repetition three set program using 90 percent of a 1RM maximum was just as effective in producing muscle strength gains as an eight-repetition program. This study further showed that if time is a factor to be considered when choosing an exercise program, then the two-repetition program is superior to the eight-repetition program. This is because the two-repetition program session took approximately two-thirds less time to complete than the eight-repetition program did.

The Importance of Physical Fitness In the Performance of Adequate Cardiopulmonary Resuscitation

The aim of the present investigation was to evaluate the influence of the physical fitness of a cardiopulmonary resuscitation (CPR) provider on the performance of and physiologic response to CPR. To this end, comparisons were made of sedentary and physically active subjects in terms of CPR performance and physiologic variables. Two study groups were established: group P (n=14), composed of sedentary, professional CPR rescuers (mean [+/-SD]; age, 34+/-6 years; VO2max, 32.5+/-5.5 mL/kg/min), and group Ex (n=14), composed of physically active, nonexperienced subjects (age, 34+/-6 years; VO2max, 44.5+/-8.5 mL/kg/min). Each subject was required to perform an 18-min CPR session, which involved manual external cardiac compressions (ECCs) on an electronic teaching mannequin following accepted standard CPR guidelines. Subjects' gas exchange parameters and heart rates (HRs) were monitored throughout the trial. Variables indicating the adequacy of the ECCs (ECC depth and the percentage of incorrect compressions and hand placements) also were determined. Overall CPR performance was similar in both groups. The indicators of ECC adequacy fell within accepted limits (ie, an ECC depth between 38 and 51 mm). However, fatigue prevented four subjects from group P from completing the trial. In contrast, the physiologic responses to CPR differed between groups. The indicators of the intensity of effort during the trial, such as HR or percentage of maximum oxygen uptake (VO2max) were higher in group P subjects than group Ex subjects, respectively (HRs at the end of the trial, 139+/-22 vs 115+/-17 beats/min, p < 0.01; percentage of VO2max after 12 min of CPR, 46.7+/-9.7% vs 37.2+/-10.4%, p < 0.05). These results suggest that a certain level of physical fitness may be beneficial to CPR providers to ensure the adequacy of chest compressions performed during relatively long periods of cardiac arrest.

Effects of Cellular Telephone Use on Driver's Mental Workload while Car Following

In this study, the effects of using a cellular telephone while driving on the driver's reaction time and subjective mental workload (SMWL) were investigated. The experiment was conducted on an expressway, in Japan. Sixteen male subjects participated in the experiment. Each subject was asked to follow a leading vehicle and to keep a constant distance while following. The subjects performed the talking task and the operating task with a cellular telephone while driving. Experience in using a cellular telephone while driving had no positive effect on reaction time. The operation task and talking task had little effect on the SMWL of the experienced subjects, but had statistically significant effects on the SMWL ofthe non-experienced subjects. Experience in using a cellular telephone while driving can reduce the SMWL of a driver, and perhaps lead to overconfidence, but such experience does not produce faster reactions. The experiments in this study were conducted under limited conditions, and therefore further investigations under various conditions are needed.

Human Operator Research with a Simulated Distillation process

This paper is concerned with the research activities on man-machine systems at the Department of industrial Engineering at Eindhoven University of Technology. The research is carried out in field situations as well as in the department laboratory by means of a digital simulation of an industrial distillation process. After a brief survey of research topics, a description is given of simulation soft- and hardware. In the second part the results of a pilot-study with the simulated process are presented. The aim of this study was to acquire experience with the simulation itself and to investigate the learning behaviour of experienced and non-experienced subjects At the same time the effects of speeding up the simulation on control performance and control behaviour were investigated.

Marijuana-produced impairments in form perception. Experienced and non-experienced subjects

1. 1. The effect of marijuana and placebo on tactual form perception ability was compared in cannabis experienced and naive subjects. A 52% impairment in form perception was observed under the marijuana condition. 2. 2. Although there was no statistically significant interaction between the drug effect and previous experience, there was a definite trend toward greater impairment for the experienced compared to the naive group.

Significance of Serum Fungal Inhibitory Factor in Dermatophytosis

An in vitro agar-diffusion system was used to assay human serum for inhibition of Trichophyton mentagrophytes growth. Sera were obtained for 30 adults representative of three major classes of susceptibility to dermatophytosis: (1) immunologically nonexperienced, (2) experienced immune, and (3) chronically infected. Although the three classes represent polar degrees of resistance/susceptibility to infection, there was no significant difference in the inhibitory power of their sera. Furthermore, nonexperienced subjects undergoing a primary infection were not found to acquire any increase in serum inhibitory activity, despite the simultaneous acquisition of a strong relative immunity. Nevertheless, other evidence suggests this unknown factor may play a role in defense against dermatophyte infection.

Cardiovascular Effects of Marihuana in Man

Twenty-eight subjects, matched by sex and Cannabis experience, received by controlled inhalation under single- and double-blind conditions 600 mg marihuana placebo and marihuana. Forearm, venous and arterial pressures, forearm blood flow, and heart rate were recorded while supine. Derived functions such as "dp/dt", regional arterial resistance, and venous compliance were calculated from these variables. (1) Placebo produced no intoxication or consistent physiological responses. (2) Marihuana produced intoxication in all Cannabis-experienced and half the non-experienced subjects. (3) Cardiovascular responses occurred in response to marihuana in the absence of intoxication, indicating that they were not psychogenically mediated. (4) Inhibition of vagal tone may contribute to the tachycardia seen with marihuana. (5) Reflexly mediated sympathetic responses may be muted in the presence of marihuana.