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921.
922.
To compare the effectiveness of training in heat and in sweat clothing in cool conditions on improving heat tolerance, two groups of active subjects (n = 6 in each) performed an interval running heat-tolerance test before and after a 7-day experimental treatment. On each treatment day the subjects attempted to complete 4 x 15 min interval treadmill running periods (a 7.5 s effort every 30 s, on 15 km h-1, 15% grade; the same exercise format as the heat-tolerance test), which were interspersed with 5-min recovery periods (total time each day = 80 min). Group 1 (heat) ran in shorts, socks and shoes in hot humid conditions, and Group 2 (sweat clothing) ran in cool conditions dressed in shorts, socks and T-shirt covered by a polyester-cotton tracksuit, over which was worn 100% nylon spray-proof pants and jacket (cotton lined) with an acrylic cloth bobble hat (beanie) on the head. Both groups displayed changes typical of heat acclimatization over the 7-day period, with significant decreases in final rectal temperature (Tr) and heart rate (HR) being evident, but no change in sweat loss. Mean skin temperature (Tsk) was similar in both groups during the training sessions (heat group: 34.8-35.7 degrees C; sweat clothing group 34.9-35.5 degrees C). After the heat-tolerance test, both groups had significantly lower Tr, Tsk and HR values than before, and sweating sensitivity (g m-2 h-1 degrees C rise in Tr) was significantly increased. There was only one significant difference between the two groups (Tsk, 20th min value). It was concluded that training in sweat clothing in cool conditions can provide the same improvements in heat tolerance as training in hot humid conditions where a fixed exercise intensity and duration are used. 相似文献
923.
924.
925.
This paper examines the earnings, work patterns, and work histories of individuals employed in the field of dance using data from a survey of graduates of the Five College Dance Department. The respondents to our survey include not only those currently working in dance, but also some who never entered the profession and many others who entered but later left the field. We find that graduate education in dance, age, and prior dance experience are highly correlated with employment in the field of dance. Our findings are similar to those of other studies on artists, in showing that the returns to dance are low and that many of those employed in dance rely on non-dance jobs to supplement their dance earnings. 相似文献
926.
927.
Many scientists and coaches are interested in mechanical power produced during cycling, and use Schoberer Rad Me\technik (SRM)
bicycle power cranks to obtain this data. However, it has been expensive and difficult to calibrate SRM cranks, causing much
of the collected data to be unreliable. We present a static method, derived from first principles, for obtaining a calibration
factor for SRM cranks.
A known mass and lever arm (chainring of a known diameter) are used to apply a known torque load to the instrument in four
positions, and the output frequencies are used to calculate the calibration factor in Hz/Nm. The reproducibility of this method
is ±0.01 Hz/Nm, which is acceptable for the application of the instrument, which is measurement of mechanical power application
by cyclists at the crank.
The method is reliable, inexpensive, and easy to set up, and will allow higher confidence in data collected using SRM power
cranks. We recommend calibration of the power meter once every six months because of the measured drift of the calibration
factor over time. 相似文献
928.
929.
930.
We examined the demographic distribution of 102 subjects with attention deficits in the Wechsler Intelligence Scale for Children-Revised (WISC-R) (Wechsler, 1974) standardization sample. Neither age nor occupational status was significant; males were overrepresented (3:1); and the West was overrepresented by 50%, largely due to the relatively high proportion of females in the West who appeared within the attention deficit sample (41% in West vs. 19% in the rest of the nation). Replication is encouraged. 相似文献