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1.
Abstract

The developmental nature of reaction time (RT) and anticipation timing (AT) performance, as well as the relationship between them, was investigated using 15 male and 15 female subjects at each of five age levels—7, 9, 11, 13, and 20 yrs. Each subject was given 40 trials for both RT and AT performance with task order counterbalanced. Results indicated that as age increased RT decreased, with males having more rapid RT than females. The two younger age groups differed from the three older groups on AT performance. RT was significantly correlated with AT (|CE| measure) for the 7, 9, and 11 yr old males but not in any other age by gender condition. Apparently neither young males nor young females have a good motor plan in memory to control AT performance. However, the more rapid RT (and thus better response initiation) of the males allows better AT performance at the younger ages. Beginning about 10–11 yrs of age, better motor plans are developed in children's memory system, leading to less reliance on rapid RT for good AT performance, and thus the correlation between RT and AT performance is not present.  相似文献   

2.
探讨不同状态焦虑水平下特质焦虑运动员对情绪信息的注意偏向.被试为高/低特质焦虑运动员各30名（两个实验各15名）,以正性情绪词、负性情绪词和中性词为刺激材料.通过诱发程序,在实验1中诱发低状态焦虑情绪,在实验2中诱发高状态焦虑情绪,然后进行点探测反应时实验.结果表明,在低状态焦虑水平下,高/低特质焦虑运动员对正性情绪词和负性情绪词的同侧位置反应时与异侧位置反应时均无显著性差异;在高状态焦虑水平下,高特质焦虑运动员的负性情绪词的同侧位置反应时短于异侧位置反应时,对负性情绪词警觉,低特质焦虑运动员负性情绪词的同侧位置反应时长于异侧位置反应时,对负性情绪词回避.在状态焦虑与特质焦虑交互作用下,特质焦虑运动员对负性情绪信息存在注意偏向.  相似文献   

3.
The aim of this study was to determine the influence of breathing frequency and tidal volume on resting heart rate variability in children aged 9 years ( n = 29) and 16 years ( n = 19). Heart rate variability was measured in four conditions: (1) without the control of ventilation followed at random by (2) a fixed breathing frequency of 12 breaths· min -1 , (3) a breathing frequency of 12 breaths· min -1 but with a fixed tidal volume of 30% vital capacity and (4) a fixed breathing frequency of 6 breaths·min -1 and a tidal volume of 30% vital capacity. A total of 128 RR intervals (the time between two spikes in the heart rate) were detected and absolute high- and low-frequency spectral components were calculated using autoregressive modelling. The younger children were unable to control ventilation to achieve conditions 3 and 4; therefore, a 2 2 2 (group 2 condition) analysis of variance was used to analyse conditions 1 and 2. There were significant interactions between group and heart rate variability conditions for the low-frequency component and the ratio of low to high frequencies ( P ? 0.001). The main effect for condition showed that at 12 breaths· min -1 with no fixed tidal volume there was a significantly higher standard deviation of the RR interval, total power and high-frequency ( P ? 0.01) and lowfrequency spectral components ( P ? 0.05) than in the condition with no ventilatory control. Across the four breathing conditions for the older participants, the high-frequency spectral component was significantly higher in the condition at 6 breaths· min -1 with a fixed tidal volume than in that with no ventilatory control ( P ? 0.005); the ratio of high to low frequencies was significantly lower for the spontaneous condition than those performed at 12 breaths· min -1 ( P ? 0.001). The results provide evidence of the need for ventilatory control when assessing short-term resting heart rate variability in children.  相似文献   

4.
The aim of this study was to determine the influence of breathing frequency and tidal volume on resting heart rate variability in children aged 9 years (n = 29) and 16 years (n = 19). Heart rate variability was measured in four conditions: (1) without the control of ventilation followed at random by (2) a fixed breathing frequency of 12 breaths x min(-1), (3) a breathing frequency of 12 breaths x min(-1) but with a fixed tidal volume of 30% vital capacity and (4) a fixed breathing frequency of 6 breaths x min(-1) and a tidal volume of 30% vital capacity. A total of 128 RR intervals (the time between two spikes in the heart rate) were detected and absolute high- and low-frequency spectral components were calculated using autoregressive modelling. The younger children were unable to control ventilation to achieve conditions 3 and 4; therefore, a 2 x 2 (group x condition) analysis of variance was used to analyse conditions 1 and 2. There were significant interactions between group and heart rate variability conditions for the low-frequency component and the ratio of low to high frequencies (P < 0.001). The main effect for condition showed that at 12 breaths x min(-1) with no fixed tidal volume there was a significantly higher standard deviation of the RR interval, total power and high-frequency (P< 0.01) and low-frequency spectral components (P < 0.05) than in the condition with no ventilatory control. Across the four breathing conditions for the older participants, the high-frequency spectral component was significantly higher in the condition at 6 breaths x min(-1) with a fixed tidal volume than in that with no ventilatory control (P < 0.005); the ratio of high to low frequencies was significantly lower for the spontaneous condition than those performed at 12 breaths x min(-1) (P < 0.001). The results provide evidence of the need for ventilatory control when assessing short-term resting heart rate variability in children.  相似文献   

5.
Abstract

This paper reports on the validity of a 14-day recall measure of leisure time physical activity (LTPA) in a sample of Australian adults (N = 986). Submaximal cycle ergometry was used to assess physical work capacity per kilogram of body mass (pwc75/kg). The self-report energy expenditure estimates were used to categorize respondents as vigorously active, moderately active, and low active/sedentary. Multiple regression analyses showed that pwc75/kg increased significantly across energy expenditure categories for adults aged less than 40 years; that the vigorous and moderate activity categories had greater mean pwc75/kg values than the low/sedentary category for 40 to 59-year-olds; and, that there were no differences in pwc75/kg between activity categories for those aged 60 years or older.  相似文献   

6.
Despite the significant health benefits of regular physical activity for older adults, only a minority achieve recommended levels. To develop effective interventions, the reasons for the low levels of physical activity in this population must be understood. The present review identifies and synthesizes qualitative studies concerning the acceptability of physical activity to community dwelling older adults. A systematic search of four electronic databases identified 10 studies meeting inclusion criteria. These were appraised, and findings were combined and compared using thematic synthesis. Older adults construed physical activity as a by-product of other activities, rather than as a purposeful activity within itself. This seemed to be linked to their self-perception as an ageing member of society, with physical activity considered irrelevant, and competing roles and responsibilities (e.g., family) taking precedence. Additionally, older adults appeared to experience conflict between maintaining their autonomy and accepting the physical and social vulnerabilities associated with ageing. As older adults do not see physical activity as purposeful within itself, interventions promoting moderate or vigorous physical activity are likely to have limited success. As even small increases in physical activity benefit older adults, future interventions may wish to target the reduction of sedentary behaviour in this population.  相似文献   

7.
Walking is a popular and easily accessible form of physical activity. However, walking instruction for older adults is based on the evidence gathered from younger populations. This study evaluated walking conditions, strength, balance, and subjective health status after a 12-week walking-training program in community-dwelling adults > 65 years old. Participants walked 1,921 m (3,158.88 steps) in 26.69 min with a heart rate of 114 beats/min. An analysis of covariance to adjust for previous exercise habits, pretest strength, and subjective health status revealed significant differences in strength and in subjective physical and mental health status between experimental and control groups. This study identified the effects of the walking-training program on community-dwelling elderly adults without changing their previous physical activities.  相似文献   

8.
PurposeThe purpose of the present study was to examine the effects of a 24-week Tai Chi exercise intervention on balance and other physical changes such as flexibility and reaction time (RT) among healthy older males.MethodsThirty-eight male subjects aged 55–65 years without prior Tai Chi experience were recruited from a local community in Shanghai, China. A 60-min Tai Chi exercise session was performed three times a week for 24 weeks. Changes in RT, sit-and-reach flexibility and balance (static balance with eyes open and closed respectively) were measured before and after the Tai Chi intervention.ResultsAfter the 24-week Tai Chi intervention, the choice RT (p < 0.05) decreased, and sit-and-reach flexibility improved (p < 0.01) over the pre-test (7.8±6.2 vs. 7.1±3.0cm). Sway length, area, X-axis deviation amplitude and Y-axis deviation amplitude performance decreased significantly after the intervention with a double-foot stance with eyes open (p < 0.05). Sway length, area and average sway speed showed a statistically significant decrease after the intervention with the double-foot stance with eyes closed. In the single-foot stance with eyes open condition, sway length and average sway speed showed a statistically significant decrease (p < 0.05).ConclusionThe 24-week Tai Chi exercise intervention had a positive influence on balance control in older males.  相似文献   

9.
The experiment was designed to (a) examine age-related differences in the control of aiming movements, and (b) determine the locus of slowing in movement execution of older adults. Fitts's (1954) index of difficulty (ID) was used to manipulate movement execution demands, and kinematics were used to examine the response characteristics. Twelve young and 12 older adults performed simple aiming movements 10 cm or 20 cm in amplitude to targets of 0.5 cm, 1.0 cm, or 2.0 cm in width, resulting in IDs ranging from 3.32 to 6.32. The results for both young and older subjects support the prediction that movement time (MT) increases as a function of ID and that older adults are significantly slower and more affected by increases in ID than the young adults. Velocity and acceleration profiles of the older adults' movements displayed very different response characteristics than those of the young adults. The results suggest that older adults emphasize accuracy of response and are concerned with the latter phase of the movement in order to contact a target accurately.  相似文献   

10.
Abstract

When learning verbal information, an important aspect of practice is the method of rehearsal, which has been demonstrated to vary developmentally. A young child practices on an instance-by-instance basis (passive rehearsal), whereas older children and adults practice several items together (active rehearsal). This study investigated the effects of passive and active rehearsal on developmental processing differences for movement reproduction. Three methods of rehearsal were used at ages 5, 7, 11, and 19 years. A child-like strategy forced the subjects to practice location cues for each of eight movements, which were presented one at a time. The mature-strategy group practiced each new position presented with two previously presented positions. A subject-determined strategy group which allowed subjects to choose their own methods of rehearsal was included as a control. Significant ANOVAs supported the hypothesis that quality of rehearsal (active over passive) is important. For the 5- and 7-year-old children, a mature strategy facilitated performance over the child-like strategy, while the use of a child-like strategy hindered the performance when compared to a self-determined or mature strategy. The results of this study indicated the importance of active rehearsal for the younger child.  相似文献   

11.
ABSTRACT

We performed a randomized, controlled trial to analyse the effects of resistance training (RT) on cognitive and physical function among older adults. Fifty participants (mean age 67 years, ~60% woman) were randomly assigned to an RT program or a control group. Participants allocated to RT performed three sets of 10-15RM in nine exercises, three times per week, for 12-weeks. Control group did not perform any exercise. Variables included cognitive (global and executive function) and physical function (gait, mobility and strength) outcomes. At completion of the intervention, RT was shown to have significantly mitigated the drop in selective attention and conflict resolution performance (Stroop test: -494.6; 95%CI: -883.1; ?106.1) and promoted a significant improvement in working memory (digit span forward: -0.6; 95%CI: ?1.0; ?0.1 and forward minus backward: -0.9; 95% CI: ?1.6; ?0.2) and verbal fluency (animal naming: +1.4, 95%CI 0.3, 2.5). No significant between-group differences were observed for other cognitive outcomes. Regarding physical function, at completion of the intervention, the RT group demonstrated improved fast-pace gait performance (?0.3; 95% CI: ?0.6; ?0.0) and 1-RM (+21.4 kg; 95%CI: 16.6; 26.2). No significant between-group differences were observed for other mobility-related outcomes. In conclusion, RT improves cognitive and physical function of older adults.  相似文献   

12.
目的观察12周惯性哑铃练习对轻度认知损害(MCI)老年人认知功能、身体活动能力、生活质量和睡眠质量的影响,并探讨认知改善与其他功能改变之间的关系。方法将45名MCI老年人随机分为干预组(n=22)和对照组(n=23)。干预组受试者进行惯性哑铃练习(3次/周,60 min/次,持续12周),对照组不进行运动干预。结果 12周后,干预组受试者阿尔茨海默病评定量表-认知部分(ADAS-Cog)总分/指令得分、蒙特利尔认知评估量表(MoCA)评分、起立行走计时(TUG)和SF-36健康调查问卷(SF-36)心理总得分均显著改善(均P<0.05)。与对照组相比,干预组受试者ADAS-Cog总分/单词回忆得分/注意力得分、简明精神量表(MMSE)评分、TUG和匹兹堡睡眠指数(PSQI)的改善程度均具有显著差异(P<0.05或P=0.05)。偏相关分析结果显示,SF-36心理总得分改变(r=-0.712)、PSQI改变(r=-0.380)与认知改善程度均呈显著负相关。结论 12周惯性哑铃练习可显著提高MCI老年人的认知功能,并对其移动能力、生活质量和睡眠质量具有积极影响,且心理和睡眠改变程度可能影响认知功能的改善效果。  相似文献   

13.
Abstract

The experiment was designed to (a) examine age-related differences in the control of aiming movements, and (b) determine the locus of slowing in movement execution of older adults. Fitts's (1954) index of difficulty (ID) was used to manipulate movement execution demands, and kinematics were used to examine the response characteristics. Twelve young and 12 older adults performed simple aiming movements 10 cm or 20 cm in amplitude to targets of 0.5 cm, 1.0 cm, or 2.0 cm in width, resulting in IDs ranging from 3.32 to 6.32. The results for both young and older subjects support the prediction that movement time (MT) increases as a function of ID and that older adults are significantly slower and more affected by increases in ID than the young adults. Velocity and acceleration profiles of the older adults' movements displayed very different response characteristics than those of the young adults. The results suggest that older adults emphasize accuracy of response and are concerned with the latter phase of the movement in order to contact a target accurately.  相似文献   

14.
王政  岳春林 《体育科研》2012,33(2):75-78,100
针对不同COMT基因型的被试者,首次利用视觉事件相关电位P3来观测被试者在长时间心算任务中COMT基因多态型与脑皮层电生理的关系。选取20名不同基因型人员作为被试者,在执行9组不同难度的心算任务后即刻,进行5 min的3-back任务,探讨健康成人数字工作记忆能力变化情况。Val/Val基因型的被试者P3波幅显著高于Val/Met基因型（P〈0.01）,但和Met/Met基因型被试者的波幅无差异;Val/Met基因型被试者在不同的工作记忆任务中都显示了最差的成绩。  相似文献   

15.
Participation rates of older people in resistance training (RT) are low despite increasing research showing many health benefits. To increase the number of older people participating in RT it is important to know what would motivate people to become involved, what motivates those who participate to continue, and the factors preventing many older people from commencing participation. To investigate these issues, a questionnaire was mailed to three groups of older people: (1) those receiving home care services, (2) members of a peak non-government seniors’ organisation and (3) those participating in a specific gym-based RT programme. In total, 1327 questionnaires were returned (response rate = 42.5%). To feel good physically and mentally were the main reasons motivating participation among all three groups, and falls prevention was identified as an important motivator for the home care respondents. Pain, injury and illness were the main barriers to participating, or continuing to participate. However, medical advice was a factor influencing participation commencement. The results suggest organisations providing RT programmes for older people should tailor the promotion and delivery of programmes to address key motivators and barriers specific to each group to increase the proportion of older people initiating and continuing to engage in RT.  相似文献   

16.
Objectives: To investigate the effects that high-velocity, low-load (HVLL) and low-velocity, high-load (LVHL) resistance exercise, performed once or twice-weekly, have on indices of functional performance (primary outcome), maximal strength, and body composition (secondary outcomes) in older adults.

Methods: In a randomised, controlled, multi-armed, parallel design, 54 moderately-highly active, but resistance exercise naïve older adults (aged 60–79 years), attended baseline and post-10-week intervention assessment sessions. Physical and functional assessments were completed, and predicted one-repetition maximums (1-RM) were obtained for eight exercises. Participants were then randomised into one of five conditions: HVLL once-weekly (HVLL1: n?=?11) or twice-weekly (HVLL2: n?=?11), LVHL once-weekly (LVHL1: n?=?10) or twice-weekly (LVHL2: n?=?11), no-exercise control condition (CON: n?=?11). The HVLL conditions completed 3 sets of 14 repetitions at 40% 1-RM and the LVHL conditions, 3 sets of 7 repetitions at 80% 1-RM. In total, 50 participants completed all testing and were included in analyses.

Results: Only LVHL2 improved 30-sec chair stand performance (p?=?.035; g?=?0.89), arm curls (p?=?.011; g?=?1.65) and grip-strength (p?=?.015; g?=?0.34) compared to CON. LVHL2 improved maximal strength compared to CON for 7/8 exercises (p?p?Conclusion: Possibly due to the lower intensity nature of the HVLL conditions, LVHL, twice-weekly was most beneficial for improving functional performance and strength in moderately-highly active older adults. Therefore, we recommend that exercise professionals ensure resistance exercise sessions have sufficient intensity of effort and volume, in order to maximise functional performance and strength gains in older adults.  相似文献   

17.
Do physical activity beliefs differ by age and gender?   总被引：1，自引：0，他引：1  
Age and gender are consistently related to physical activity (PA), yet theoretical explanation for these associations is scant. The present study compared the mean values and correlations of a population sample, divided by gender and age group, with respect to theory of planned behavior beliefs (behavioral, normative, and control) and PA. Participants were a sample (N=6,739) of adults (M age=49.65, SD=16.04) who completed measures of social and health demographics, theory of planned behavior beliefs, and self-reported PA. Mean analyses identified greater perceived control over PA for seniors than for young and middle-aged adults (N>.025). Belief-behavior correlations, however, were not different across age and gender in 24 of 26 tests (q<.19). Thus, PA beliefs are invariant across age and gender with the exception of mean levels of perceived control, which are lower among younger adults than older adults. Factors such as early parenthood and career demands were considered the likely reasons for differences. Overall, the evidence suggests that adapting theoretical models for specific age groups or based on gender may not be necessary.  相似文献   

18.
Abstract

The purpose of this study was to compare reaction time (RT) and fractionated RT components (premotor and motor times) between normal and postcontraction conditions. Twelve participants performed 20 trials each of control and postcontraction RT conditions. For the control condition, participants executed a learned, rapid, knee-extension contraction response to an auditory stimulus. The postcontraction condition was identical to the control condition except that the participants performed a 3-s isometric contraction of the knee extensor muscles prior to an auditory stimulus. Muscle activity was recorded from the quadriceps muscle group. Results indicated that the postcontraction condition was significantly faster than the control condition for the average RT, premotor time, and motor time. It was concluded that reaction time, processing time, and muscle contraction time for a learned task could be significantly reduced following an isometric contraction.  相似文献   

19.
The purpose of this study was to compare reaction time (RT) and fractionated RT components (premotor and motor times) between normal and postcontraction conditions. Twelve participants performed 20 trials each of control and postcontraction RT conditions. For the control condition, participants executed a learned, rapid, knee-extension contraction response to an auditory stimulus. The postcontraction condition was identical to the control condition except that the participants performed a 3-s isometric contraction of the knee extensor muscles prior to an auditory stimulus. Muscle activity was recorded from the quadriceps muscle group. Results indicated that the postcontraction condition was significantly faster than the control condition for the average RT, premotor time, and motor time. It was concluded that reaction time, processing time, and muscle contraction time for a learned task could be significantly reduced following an isometric contraction.  相似文献   

20.
The RT3 is a relatively new triaxial accelerometer that has replaced the TriTrac. The aim of this study was to validate the RT3 against doubly labeled water (DLW) in a free-living, mixed weight sample of adults. Total energy expenditure (TEE) was measured over a 15-day period using DLW. Activity-related energy expenditure (AEE) was estimated by subtracting resting energy expenditure and thermic effect of feeding from TEE. The RT3 triaxial accelerometer was worn over 14 consecutive days. TEE and AEE were estimated using the RT3 proprietary equation. Thirty-six adults ages 18–56 years (56% women) with an average weight of 75.9 kg (SD = 14.8) completed all measurements. Compared to DLW, the RT3 underestimated TEE by 539 kJ (4%) and AEE by 485 kJ (15%) on average. The RT3 provided a relatively accurate assessment of free-living activity-related energy expenditure at the group level and generally underestimated total and activity-related energy expenditure compared to DLW.  相似文献   

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