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991.
Croteau KA Richeson NE Farmer BC Jones DB 《Research quarterly for exercise and sport》2007,78(5):401-406
This study investigated the effect of a 12-week pedometer-based intervention on daily step counts of 147 older adults randomly assigned to an intervention or wait-list control group (M age = 72.9 years, SD = 8.8). The intervention group significantly increased their daily step counts after 12 weeks (M=639, SD=2239) and continued to significantly increase during a 12-week maintenance period (M=680, SD=1721). The control group exhibited no change during the control period (M = -393, SD=2050) but had a significant increase in daily step counts (M=1580, SD=2305) when enrolled in the intervention. The pedometer-based intervention was effective in increasing participants' daily step counts. 相似文献
992.
Although the importance of high motivation to engage in deliberate practice has been acknowledged, no research has directly tested this hypothesis. Therefore, the present study examined this relation in adolescent elite chess players by means of a questionnaire. In addition, to provide an explanation for dropout among promising chess players, differences in motivation between persistent and dropout chess players were analyzed. Competitiveness and the will to excel proved to be predictors of investments in deliberate practice. Moreover, achievement motivation and chess-specific motivation differed to a certain extent between persisters and dropouts. Our results suggest that motivation to engage in deliberate practice not only contains elements of the will to improve performance, but also of the will to attain exceptional levels of performance. 相似文献
993.
Effect of different recovery patterns on repeated-sprint ability and neuromuscular responses 总被引:1,自引:0,他引:1
We examined the effect of recovery pattern on mechanical and neuromuscular responses in active men during three repeated-sprint ability tests consisting of ten 6-s cycling sprints. Within each test, the recovery duration was manipulated: constant, increasing, and decreasing recovery pattern. Maximal voluntary contractions of the knee extensors were performed before and after the repeated-sprint ability tests to assess strength and electromyographic activity [root mean square (RMS)] of the quadriceps muscle. We observed different fatigue patterns for peak and mean power output between recovery patterns, with earlier decrements recorded during the increasing recovery pattern. Total work performed over the ten sprints was also lower in the increasing recovery pattern (43.8 +/- 5.4 kJ; P < 0.05). However, the decreasing recovery pattern induced a greater overall power output decrement across the sprints (-15.8%; P < 0.05), compared with the increasing recovery pattern (-5.1%) but not the constant recovery pattern (-10.1%). The decreasing recovery pattern was also associated with higher post-sprint RMS values (+16.2%; P < 0.05). Therefore, the recovery pattern within successive short sprints may influence repeated-sprint ability, and may lead to greater post-sprint neuromuscular adjustments when recovery intervals decrease between sprints. We conclude that peripheral impairments caused the major differences in repeated-sprint ability between recovery patterns. 相似文献
994.
In this study, we examined the anthropometric dimensions of powerlifters across various body mass (competitive bodyweight) categories. Fifty-four male Oceania competitive powerlifters (9 lightweight, 30 middleweight, and 15 heavyweight) were recruited from one international and two national powerlifting competitions held in New Zealand. Powerlifters were assessed for 37 anthropometric dimensions by ISAK (International Society for the Advancement of Kinanthropometry) level II and III accredited anthropometrists. The powerlifters were highly mesomorphic and had large girths and bony breadths, both in absolute units and when expressed as Z(p)-scores compared through the Phantom (Ross & Wilson, 1974). These anthropometric characteristics were more pronounced in heavyweights, who were significantly heavier, had greater muscle and fat mass, were more endo-mesomorphic, and had larger girths and bony breadths than the lighter lifters. Although middleweight and heavyweight lifters typically had longer segment lengths than the lightweights, all three groups had similar Zp-scores for the segment lengths, indicating similar segment length proportions. While population comparisons would be required to identify any connection between specific anthropometric dimensions that confer a competitive advantage to the expression of maximal strength, anthropometric profiling may prove useful for talent identification and for the assessment of training progression in powerlifting. 相似文献
995.
The aims of the study were to modify the training impulse (TRIMP) method of quantifying training load for use with intermittent team sports, and to examine the relationship between this modified TRIMP (TRIMP(MOD)) and changes in the physiological profile of team sport players during a competitive season. Eight male field hockey players, participating in the English Premier Division, took part in the study (mean+/-s: age 26+/-4 years, body mass 80.8+/-5.2 kg, stature 1.82+/-0.04 m). Participants performed three treadmill exercise tests at the start of the competitive season and mid-season: a submaximal test to establish the treadmill speed at a blood lactate concentration of 4 mmol . l(-1); a maximal incremental test to determine maximal oxygen uptake ([V]O(2max)) and peak running speed; and an all-out constant-load test to determine time to exhaustion. Heart rate was recorded during all training sessions and match-play, from which TRIMP(MOD) was calculated. Mean weekly TRIMP(MOD) was correlated with the change in [V]O(2max) and treadmill speed at a blood lactate concentration of 4 mmol x l(-1) from the start of to mid-season (P<0.05). The results suggest that TRIMP(MOD) is a means of quantifying training load in team sports and can be used to prescribe training for the maintenance or improvement of aerobic fitness during the competitive season. 相似文献
996.
Boisnoir A Decker L Reine B Natta F 《Sports biomechanics / International Society of Biomechanics in Sports》2007,6(2):215-223
Biomechanical analyses using synchronized tools [electromyography (EMG), motion capture, force sensors, force platform, and digital camera] are classically performed in a laboratory environment that could influence the performance. We present a system for studying the running sprint start that synchronizes motion capture, EMG, and ground reaction force data. To maximize motion capture (Vicon 612 with six cameras), a special dim environment was created in the stadium. "Classical" tools were combined with "purpose-built" tools intended to analyse the different aspects of movement. For example, a synchronization system was built to create a common time-base for all data recordings and a portable EMG system was synchronized by a cable that was "disconnected" by the athlete's movement out of the blocks. This disconnection represented an independent event recorded by different tools. A "gap" was measured for some sprint start events between kinetic and kinematic (motion capture) data. Calibration results, measurements of time "gap", and duration of the independent event were used to validate the accuracy of motion capture and the synchronization system. The results validate the entire experimental set-up and suggest adjustment values for motion capture data. This environment can be used to study other movements and can easily be applied to several sports. 相似文献
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