We compared 7 methods of measuring visual fatigue--accommodation power, visual acuity, pupil diameter, critical fusion frequency (CFF), eye movement velocity, subjective rating of visual fatigue, and task performance--for their sensitivity to visual load. In the experiment, 10 participants performed a monitoring task at 2 viewing distances, read articles under 2 levels of screen contrast, and tracked visual targets at 2 different speeds. The same measurement techniques, excluding pupil diameter and eye movement velocity, were compared by extending the task time from 20 to 60 min with the same VDT tasks to test for possible improvement in sensitivity. The results indicated that sensitivities of accommodation power, visual acuity, and CFF were greatly improved by a longer task period, but these 3 measurement techniques did not distinguish among tasks. Pupil diameter, eye movement velocity, and subjective rating of visual fatigue were sensitive in differentiating tracking from reading and monitoring tasks. Eye movement velocity and subjective rating were sensitive to the changes in target velocity of the tracking task. Although task performance was not directly comparable to other measurement techniques, it helped to ensure that participants maintained the same performance level by devoting more resources to the high-load conditions. Actual or potential applications of this research include using some of these assessment techniques for the design of adaptive displays.

Improperly designed hand tools and sports equipment contribute to undesired injuries and accidents. The idea of bending the tool, not the wrist, has been applied to sports equipment. According to Bennett's idea, the design of an ideal handle angle should be in the range of 14 degrees to 24 degrees. Thus design of the handle angle in the sport of fencing is also important. A well-designed handle angle could not only reduce ulnar deviation to avoid wrist injury but also enhance performance. An experiment with several different handle angles was conducted to analyze the effect on performance. Analysis showed an angle of 18 degrees to 21 degrees provided best overall performance in fencing.

The strength of five working muscle groups of the lower arms of 8 male fencers, including adductor pollicis, extensor carpi radialis, flexor carpi radialis, extensor carpi ulnaris, and flexor carpi ulnaris, were examined during competition. Root mean square values of muscular electromyographic signals indicated that the shape of foil handles significantly influenced distribution of working strength of each muscle group. Use of the Pistol-Viscounti type of foil handle showed better distribution of strength among the 5 muscle groups than did other types of foils. Using the Pistol-Viscounti foil handle not only reduced muscular fatigue but also lessened cumulative trauma symptoms while holding a foil for a long duration.

A long-term use of ina pp ro p riate handle t yp e and poor handle angle ma y result in cumulative trauma disorders (CTDs) for wrist es p eciall y during fencing. This research evaluated the influences of handle t yp es on workload of muscle strength distributed to the wrist during a fencing game via the EMG data. Subsequently, use different angle of handles to evaluate the fatigue p erformance on wrist as well as p re-and p ost-ex p eriment grip difference. The results show that the handle t yp e will affect fencers' muscle strength distributed to the wrist. Itshows that a viscounti-t yp e handle has equall y strengths for all muscle grou p s. Other t yp es of grip are relativel y eas y to cause muscle fatigue. Different handle angles will not affect on the average workload of the wrist, but it will influence the strength of grasp. The handle angles in 210 and 240 show a vulnerabilit y to fatigue for wrist muscles. We concluded that, for handle t yp e, the viscounti-t yp e handle is more a pp ro p riate with its handle angle at 210 to have better p erformance in effective hit rate and hit accurac y , but lead muscles to be easil y fatigue. A handle angle at 240 shows a p oor p erformance for hit rate and hit accurac y for fencers.

Subjects of this study are 12 persons divided into two even groups by the difference of involvement degree of playing video games. The subjects' brain waves of frontal lobe, parietal lobe, occipital lobe and temporal lobe are examined to find out how the subjects are affected after one hour of playing video games. The results show that a-waves and p-waves of the four lobes have no significant change. The percentages differences of relation between a-waves and p-waves are statistically significant. It was found that the a waves of right frontal lobe are larger than those of the left frontal lobe in F3-F4. The reason of the opposing results may lie on the variable of playing time, that is, one hour of playing video games may be too short after all.