摘要:

RODGERS, C. D., J. L. VANHEEST, and C. L. SCHACHTER. Energy expenditure during submaximal walking with Exerstriders.Med. Sci. Sports Exerc., Vol. 27, No. 4, pp. 607–611, 1995. This study was designed to determine whether Exerstriding, a modified form of walking using walking sticks (Exerstriders), resulted in an augmented cardiorespiratory response and a greater energy expenditure than when walking without Exerstriders. Female subjects (23.6 ± 4.0 yr; 58.5 ± 5.5 kg) completed two randomly assigned trials of treadmill walking (6.7 km·h-1; 0% grade; 30 min.) with (Exerstrider ± (E)) and without Exerstriders (Control (C)). Mean oxygen consumption (E = 20.5 ± 1.2 ml·min-1·kg-1; C = 18.3 ± 2.5 ml·min-1·kg-1), heart rate (E = 132.5 ± 19.2 beats·min-1; C = 121.5 ± 21.2 beats·min-1) and respiratory exchange ratio (E = .82 ± .03; C = .78 ± .04) were significantly greater (P≥ 0.05) while walking with Exerstriders. Total caloric expenditure was also significantly greater during the Exerstrider condition (E = 173.7 ± 20.9 kcal; C = 140.7 ± 27.2 kcal.). In contrast, the rating of perceived exertion did not differ significantly between the two conditions. These data suggest that Exerstriding provides a means to increase caloric expenditure during submaximal walking, a factor that may be of critical importance in enhancing health benefits–such as improved body composition and aerobic capacity–typically associated with walking programs.

ISSN:0195-9131    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

HOLIDAY, D. B., J. E. BALLARD, and B. C. McKEOWN. PRESS-related statistics: regression tools for cross-validation and case diagnostics.Med. Sci. Sports Exerc., Vol. 27, No. 4, pp. 612–620, 1995. In the health science literature, a common approach of validating a regression equation is data-splitting, where a portion of the data fits the model (fitting sample) and the remainder (validation sample) estimates future performance. TheR2and SEE obtained by predicting the validation sample with the fitting sample equation is a proper estimate of future performance, tending to correct for the natural upward bias of theR2and SEE obtained from fitting sample alone. Data-splitting has several disadvantages, however. These include: 1) difficulty, arbitrariness, and inconvenience of matching samples; 2) the need to report two sets of statistics to determine homogeneity; and 3) the lack of equation stability due to diluted sample size. The PRESS statistic and associated residuals do not require the data to be split, yield alternative unbiased estimates ofR2and SEE, and provide useful case diagnostics. This procedure is easy to use, is widely available in modern statistical packages, but is rarely utilized. The two methods are contrasted here using a simulation from original data for predicting body density from anthropomctric measurements of a group of 117 women. The PRESS approach is particularly appropriate for smaller datascts; methods of reporting these statistics are recommended.

ISSN:0195-9131    

出版商:OVID    

年代:1995

数据来源: OVID

ISSN:0195-9131    

出版商:OVID    

年代:1995

数据来源: OVID

ISSN:0195-9131    

出版商:OVID    

年代:1995

数据来源: OVID