Comparing the Effectiveness of Physical Exercise Intervention and Melatonin Supplement in Improving Sleep Quality in Children with ASD.

PURPOSE: Previous studies have demonstrated that physical exercise can modulate the endogenous melatonin level in children with autism spectrum disorder (ASD) and improve their sleep quality. However, it remains unclear whether physical exercise or melatonin supplement, or a combination of both, is more effective in improving sleep quality in this population. The purpose of this study is to answer this research question by comparing the effectiveness of three types of interventions (physical exercise vs. melatonin supplement or a combination of both) in improving sleep quality in children with ASD. METHODS: Sixty-two (62) children diagnosed with ASD were randomly assigned to one of four groups: cycling (n = 18), melatonin supplement (n = 14), a combination of both (n = 12), and placebo control group (n = 18). Four (4) sleep parameters (sleep efficiency, sleep onset latency, sleep duration, and wake after sleep onset) were assessed. RESULTS: The results revealed a significant improvement in sleep efficiency, sleep onset latency, and sleep duration in all of the interventions, but not in the placebo control group. However, no significant group differences were found among the interventions (ps > .05). CONCLUSION: Our findings suggest similar effectiveness of physical exercise and melatonin supplementation in improving sleep quality in children with ASD.

Association between time spent on smartphones and digital eye strain: A 1-year prospective observational study among Hong Kong children and adolescents.

Prolonged electronic screen use can cause digital eye strain. It can be difficult to rectify due to increasing smartphone reliance, potentially leading to serious public health problems. To investigate the association between time spent on smartphones and digital eye strain (DES) among Hong Kong Chinese school-aged children. Of a total of 1,508 students (748 males, 49.6%) from 8 to 14 years old (mean age = 10.91 years, SD = 2.01) who provided valid data on DES, the 1,298 (86%) who completed the DES questionnaire at 1-year follow-up were included in the analysis. DES was measured using a 10-item scale, and the sum of the 10 dichotomised scores was used as the DES total score. The most commonly reported symptoms were eye fatigue (n = 804, 53.3%), blurred vision (changing from reading to distance viewing) (n = 586, 38.9%), and irritated or burning eyes (n = 516, 34.2%). The DES total scores at baseline and 1-year follow-up were 2.91 (SD = 2.90) and 3.20 (SD = 3.19), respectively. Linear regression controlling for demographic and socio-economic confounders showed that participants with baseline smartphone usage of 241 + min/d had a significantly higher baseline total DES score than those with baseline smartphone usage of 0-60 min/d (2.44 vs 3.21, P < 0.001), and participants with baseline smartphone usage of 181-240 min/d had a significantly higher 1-year follow-up total DES score than those with baseline smartphone usage of 0-60 min/d (2.80 vs 3.50, P = 0.003).

Bedtime smart device usage and accelerometer-measured sleep outcomes in children and adolescents.

PURPOSE: We analyzed the association between bedtime smart device usage habits and accelerometer-measured sleep outcomes (total sleeping time, sleep efficiency, and wake after sleep onset) in Hong Kong children and adolescents aged 8-14. METHODS: A total of 467 students in Hong Kong participated in this study from 2016 to 2017. They self-reported their bedtime smart device usage habits. The primary caregiver of each participant was also invited to complete a self-administered questionnaire about the family's social-economic status and bedtime smart device usage habits. An ActiGraph GT3X accelerometer was used to assess participants' 7-day sleep outcomes. RESULTS: The mean age of the participants was 10.3 (SD 1.9), and 54% were girls. Among the participants, 27% (n = 139) used a smart device before sleep, and 33% (n = 170) kept the smart device on before sleep. In total, 27% (n = 128) placed the smart device within reach before sleep, 23% (n = 107) would wake up when notifications were received, and 25% (n = 117) immediately checked the device after being awakened by a notification. Multiple regression controlling for age, sex, socio-economic status, and other confounders showed that those who woke up after receiving a notification had a statistically longer sleeping time (19.7 min, 95% CI: 0.3, 39.1, p = 0.046), lower sleep efficiency (- 0.71%, 95% CI - 1.40, - 0.02, p = 0.04), and a longer wake after sleep onset (2.6 min, 95% CI: 0.1, 5.1, p = 0.045) than those who did not. Nonetheless, all primary caregivers' bedtime smart device habits were insignificantly associated with all sleep outcomes of their children. CONCLUSION: Those who woke up after receiving smart device notifications had lower sleep efficiency and longer wake after sleep onset than those who did not, and they compensated for their sleep loss by lengthening their total sleep time.

Improving Executive Function of Children with Autism Spectrum Disorder through Cycling Skill Acquisition.

PURPOSE: Executive dysfunction has been widely reported in children with autism spectrum disorder (ASD). Although studies have clearly documented the cognitive benefits of physical exercise on cognition in children, similar studies in children with ASD are scarce. The purpose of this study was to compare the effect of cognitively engaging exercise and noncognitively engaging exercise on executive function in children with ASD. METHODS: Sixty-two children diagnosed with ASD (50 males and 12 females, Mage = 9.89 ± 1.53 yr, Mheight = 1.43 ± 0.15 m, and Mweight = 44.69 ± 11.96 kg) were randomly assigned into three groups: learning to ride a bicycle (n = 22), stationary cycling (n = 20), and control (n = 20). Four executive function components (planning, working memory, flexibility, and inhibition) were assessed. RESULTS: Results revealed significant improvements in all executive function components in the learning to ride a bicycle group (Ps < 0.05) but not in the other two groups after controlling for age and IQ. CONCLUSION: Our findings highlight the value of cognitive engagement in exercise programs designed to improve cognition in children with ASD.

Validation of Self-Reported Smartphone Usage Against Objectively-Measured Smartphone Usage in Hong Kong Chinese Adolescents and Young Adults.

OBJECTIVE: This study evaluated the validity of self-reported smartphone usage data against objectively-measured smartphone usage data by directly tracking the activities in the participants' smartphone among Chinese adolescents and young adults in Hong Kong. METHODS: A total of 187 participants were recruited (mean age 19.4, 71.7% female) between 2017 and 2018. A smartphone usage tracking app was installed on all participants' smartphone for 7 consecutive days. After the 7-day monitoring period, they completed a selfadministered questionnaire on smartphone usage habits. RESULTS: Although the correlation between self-reported and objectively-measured total smartphone usage time was insignificant (ρ=-0.10, p=0.18), in three out of the four usage domains were positively and significantly correlated, namely social network (ρ=0.21, p=0.005), instant messaging (ρ=0.27, p<0.001), and games (ρ=0.64, p<0.001). Participants' self-report of the total time spent on smartphones exceeded the objective data by around 760 min per week (self-reported 1,930.3 min/wk vs. objectively-measured 1,170.7 min/wk, p<0.001). Most of the over-reporting was contributed by the web browsing domain (self-reported 447.8 min/wk vs. objectively-measured 33.3 min/wk, p<0.001). CONCLUSION: Our results showed large discrepancies between self-reported smartphone and objectively-measured smartphone usage except for self-reported usage on game apps.

Temporal association between objectively measured smartphone usage, sleep quality and physical activity among Chinese adolescents and young adults.

We studied the association between objectively measured smartphone usage and objectively measured sleep quality and physical activity for seven consecutive days among Hong Kong adolescents and young adults aged 11-25 years (n = 357, 67% female). We installed an app that tracked the subjects' smartphone usage and had them wear an ActiGraph GT3X accelerometer on their wrist to measure their sleep quality and physical activity level. Smartphone usage data were successfully obtained from 187 participants (52.4%). The participants on average spent 2 h 46 min per day on their smartphone. Multilevel regression showed that 1 min of daytime smartphone usage was associated with 0.07 min decrease in total sleeping time that night (p = .043, 95% confidence interval [CI]: -0.14, -0.003). Broken down for different usage purposes, 1 min of daytime social network usage and games and comics was associated with a 0.28 (p = .02, 95% CI: -0.52, -0.04) min and 0.18 min (p = .01, 95% CI: -0.32, -0.04) decrease in total sleeping time that night, respectively. One minute of daytime smartphone usage was associated with an increase of 4.55 steps in the number of steps (p = .001, 95% CI: 1.77, 7.34) on the next day. To conclude, time spent on a smartphone in the daytime was associated with total sleeping time that night and number of steps the next day, but was not associated with sleep efficiency, wake after sleep onset and moderate-to-vigorous-intensity activity (MVPA) among Hong Kong adolescents and young adults.

Investigating the Matching Relationship between Physical Exercise and Stereotypic Behavior in Children with Autism.

PURPOSE: Physical exercise has been shown to be effective in reducing stereotypic behaviors in children with autism spectrum disorder. One possible mechanism concerns the matching hypothesis between exercise and behavior. The present study sought to examine this matching exercise-behavior relationship. METHODS: Participants (N = 21, 17 males and 4 females, Mage = 11.07 ± 1.44 yr, Mheight = 1.46 ± 0.99 m, and Mweight = 40.60 ± 8.25 kg), with observable forms of hand-flapping and body-rocking stereotypic behaviors, underwent three separate days of conditions, one for the control condition, one for the 10-min ball-tapping exercise condition, and one for the 10-min jogging condition, in a randomized order. The frequency of each type of stereotypic behavior was videotaped from 15 min before to 60 min after the exercise. RESULTS: Results revealed that only hand-flapping stereotypic behaviors were significantly reduced in the ball-tapping exercise condition (P < 0.017), whereas only body-rocking stereotypic behaviors were significantly reduced in the jogging exercise condition (P < 0.017). However, the behavioral benefit diminished at 45 min after the respective exercise. CONCLUSION: Physical exercise should be topographically matched with stereotypic behavior to produce desirable behavioral benefits in children with autism spectrum disorder.

Association between Time Spent on Smart Devices and Change in Refractive Error: A 1-Year Prospective Observational Study among Hong Kong Children and Adolescents.

This study examined the association between smart device usage and the 1-year change in refractive error among a representative sample of Hong Kong children and adolescents aged 8-14 years. A total of 1597 participants (49.9% male, mean age 10.9, SD 2.0) who completed both baseline (2017-2018) and 1-year follow-up (2018-2019) eye examinations were included in the present study. The non-cycloplegic auto-refractive error was measured and the average spherical equivalent refraction (SER) was analyzed. The participants also self-reported their smart device usage at baseline. Multivariate regression adjusted for age, sex, baseline SER, parents' short-sightedness, BMI, time spent on moderate-to-vigorous physical activity (MVPA), and caregiver-reported socio-economic status showed that, compared with the reference group (<2 h per day on both smartphone and tablet usages), those who spent ≥2 h per day using a smartphone and <2 h per day using a tablet had a significantly negative shift in refractive error (1-year change in SER -0.25 vs. -0.09 D, p = 0.01) for the right eye, while the level of significance was marginal (1-year change -0.28 vs. -0.15 D, p = 0.055) for the left eye. To conclude, our data suggested spending at most 2 h per day on both smartphones and tablets.

Brief Report: Impact of a Physical Exercise Intervention on Emotion Regulation and Behavioral Functioning in Children with Autism Spectrum Disorder.

Problems with emotion regulation and behavior are often reported in children with autism spectrum disorders (ASD). This pilot study examined the effect of physical exercise on emotion regulation and behavioral functioning in children with ASD. Twenty-seven children aged 8-12 years were randomized into either an exercise intervention group (n = 15) or a control group (n = 12). The intervention group received a 12-week jogging intervention. Children's parents completed the Emotion Regulation Checklist and the Child Behavior Checklist pre- and post-intervention. The intervention group demonstrated significant improvement in emotion regulation and reduction in behavioral problems (ps < .05). Future studies should explore the mechanisms underlying the effects of physical exercise on emotion regulation and behavior in children with ASD.

The Role of Movement-Specific Reinvestment in Visuomotor Control of Walking by Older Adults.

OBJECTIVES: The aim of this study was to examine the association between conscious monitoring and control of movements (i.e., movement-specific reinvestment) and visuomotor control during walking by older adults. METHOD: The Movement-Specific Reinvestment Scale (MSRS) was administered to 92 community-dwelling older adults, aged 65-81 years, who were required to walk along a 4.8-m walkway and step on the middle of a target as accurately as possible. Participants' movement kinematics and gaze behavior were measured during approach to the target and when stepping on it. RESULTS: High scores on the MSRS were associated with prolonged stance and double support times during approach to the stepping target, and less accurate foot placement when stepping on the target. No associations between MSRS and gaze behavior were observed. DISCUSSION: Older adults with a high propensity for movement-specific reinvestment seem to need more time to "plan" future stepping movements, yet show worse stepping accuracy than older adults with a low propensity for movement-specific reinvestment. Future research should examine whether older adults with a higher propensity for reinvestment are more likely to display movement errors that lead to falling.

The role of attentional focus on walking efficiency among older fallers and non-fallers.

BACKGROUND: This study evaluated the effect of attentional focus instructions on movement efficiency during a level-ground walking task in older adults with and without a history of falls. METHODS: One hundred and thirty-four community-dwelling older adults were categorised into older fallers (OF) (n = 37) and older non-fallers (ONF) (n = 97). Each participant was instructed to walk at a self-selected pace along a 6 m walkway under three attentional focus conditions (i.e. internal, goal-directed and control) for a total of nine trials. Average muscle activity indices of lower limb co-contractions were measured using surface electromyography. RESULTS: Both shank and thigh muscle co-contractions were higher in OF than in ONF in all three conditions. OF also demonstrated higher shank muscle co-contraction under the internal relative to the goal-directed condition, with no such change observed in ONF. CONCLUSION: Despite no significant between-group differences in functional balance and balance confidence, relative walking inefficiencies were observed in OF compared with ONF. This finding demonstrates the debilitating consequences of falling that can occur with relative independence from various physiological or psychological factors that are commonly associated with falling and used to rationalise behavioural change. We also provide evidence that OF are more susceptible to conditions that provoke them to allocate attention internally. Therefore, in clinical contexts (e.g. gait rehabilitation), verbal instructions that refer to body movements (internal focus) might serve to compromise movement efficiency in older adults with a history of falls. Such changes will, theoretically, lessen the ability to react efficiently to changing environments experienced in daily life.

Psychometric Properties and Demographic Correlates of the Smartphone Addiction Scale-Short Version Among Chinese Children and Adolescents in Hong Kong.

Nearly all children and teens in Hong Kong own a smartphone. There is currently no validated instrument that measures whether they use their phone too much. This study tested the psychometric properties of a translated Chinese version of the Smartphone Addiction Scale-Short Version (SAS-SV) and examined the demographic correlates of smartphone addiction among Hong Kong children and adolescents. A total of 1,901 primary school children and secondary school pupils were recruited from 15 Hong Kong schools. Furthermore, 1,797 primary caregivers were asked to complete a self-administered questionnaire on their socioeconomic status and educational attainment. The study used exploratory factor analysis (EFA) to identify the factor structure of SAS-SV for half the participants (n = 951), while confirmatory factor analysis (CFA) was used to assess the goodness-of-fit of EFA models for the remaining half (n = 951). Spearman correlations were used to assess the convergent validity of the SAS-SV, taking account of time spent by subjects on phones per day, the Smart Device Addiction Screening Tool (SDAST), the Pittsburgh Sleep Quality Index (PSQI), the Multidimensional Scale of Perceived Social Support (MSPSS), and the Center for Epidemiological Studies Depression Scale for Children (CES-DC). EFA generated a three-factor model (with factors labeled "dependency," the incidence of a "problem," and "time spent"). CFA confirmed this model yielded an acceptable goodness-of-fit (Comparative Fit Index = 0.96, Tucker Lewis Index = 0.95, and root-mean-square error of approximation = 0.06). SAS-SV was positively correlated with SDAST (ρ = 0.59), PSQI (ρ = 0.29), and CES-D (ρ = 0.35), and negatively correlated with MSPSS (ρ = -0.10). A linear regression model showed that female adolescents, those with highly educated caregivers and those who spent more time using smartphones on their holidays, had on average higher SAS-SV scores, meaning they showed greater vulnerability to becoming addicted. The study found that SAS-SV is a valid scale for estimating excessive smartphone use among Hong Kong children and adolescents.

Application of Analogy in Learning Badminton Among Older Adults: Implications for Rehabilitation.

This study aimed to investigate the effect of applying analogy instruction for older adults in learning the badminton high serve. It was hypothesized that acquiring this motor skill by analogy instruction would bring the benefits of more robust and durable motor performance under stress and over time. A group of older adults learned badminton high serves by either a set of explicit instructions or an analogy instruction that represented the biomechanical metaphor of the badminton high serve. They were then invited to perform the motor task in two testing conditions: a stress transfer test and a retention test. It was found that the analogy instruction group improved the motor performance in badminton high serves during the learning blocks and maintained high levels of performance in the stress transfer test and retention test, whereas the explicit instruction group did not show any improvement. The analogy instruction group had better motor performance than the explicit instruction group during the stress transfer test. The results showed that analogy instruction facilitated the acquisition of new motor skills in older adults, and the benefit of stress resistance was also evidenced.

Study protocol for a randomised controlled trial examining the association between physical activity and sleep quality in children with autism spectrum disorder based on the melatonin-mediated mechanism model.

INTRODUCTION: Sleep disturbance is commonly observed in children with autism spectrum disorders (ASD). Disturbed sleep may exacerbate the core symptoms of ASD. Behavioural interventions and supplemental melatonin medication are traditionally used to improve sleep quality, but poor sustainability of behavioural intervention effects and use of other medications that metabolise melatonin may degrade the effectiveness of these interventions. However, several studies have suggested that physical activity may provide an effective intervention for treating sleep disturbance in typically developing children. Thus, we designed a study to examine whether such an intervention is also effective in children with ASD. We present a protocol (4 December 2017) for a jogging intervention with a parallel and two-group randomised controlled trial design using objective actigraphic assessment and 6-sulfatoxymelatonin measurement to determine whether a 12-week physical activity intervention elicits changes in sleep quality or melatonin levels. METHODS AND ANALYSIS: All eligible participants will be randomly allocated to either a jogging intervention group or a control group receiving standard care. Changes in sleep quality will be monitored through actigraphic assessment and parental sleep logs. All participants will also be instructed to collect a 24-hour urine sample. 6-sulfatoxymelatonin, a creatinine-adjusted morning urinary melatonin representative of the participant's melatonin levels, will be measured from the sample. All assessments will be carried out before the intervention (T1), immediately after the 12-week intervention or regular treatment (T2), 6 weeks after the intervention (T3) and 12 weeks after the intervention (T4) to examine the sustainability of the intervention effects. The first enrolment began in February 2018. ETHICS AND DISSEMINATION: Ethical approval was obtained through the Human Research Ethics Committee, Education University of Hong Kong. The results of this trial will be submitted for publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT03348982.

Diagnosis checking of statistical analysis in RCTs indexed in PubMed.

BACKGROUND: Statistical analysis is essential for reporting of the results of randomized controlled trials (RCTs), as well as evaluating their effectiveness. However, the validity of a statistical analysis also depends on whether the assumptions of that analysis are valid. OBJECTIVE: To review all RCTs published in journals indexed in PubMed during December 2014 to provide a complete picture of how RCTs handle assumptions of statistical analysis. METHODS: We reviewed all RCTs published in December 2014 that appeared in journals indexed in PubMed using the Cochrane highly sensitive search strategy. The 2014 impact factors of the journals were used as proxies for their quality. The type of statistical analysis used and whether the assumptions of the analysis were tested were reviewed. RESULTS: In total, 451 papers were included. Of the 278 papers that reported a crude analysis for the primary outcomes, 31 (27·2%) reported whether the outcome was normally distributed. Of the 172 papers that reported an adjusted analysis for the primary outcomes, diagnosis checking was rarely conducted, with only 20%, 8·6% and 7% checked for generalized linear model, Cox proportional hazard model and multilevel model, respectively. Study characteristics (study type, drug trial, funding sources, journal type and endorsement of CONSORT guidelines) were not associated with the reporting of diagnosis checking. CONCLUSION: The diagnosis of statistical analyses in RCTs published in PubMed-indexed journals was usually absent. Journals should provide guidelines about the reporting of a diagnosis of assumptions.

The quality of the reported sample size calculations in randomized controlled trials indexed in PubMed.

BACKGROUND: There are limited data on the quality of reporting of information essential for replication of the calculation as well as the accuracy of the sample size calculation. We examine the current quality of reporting of the sample size calculation in randomized controlled trials (RCTs) published in PubMed and to examine the variation in reporting across study design, study characteristics, and journal impact factor. We also reviewed the targeted sample size reported in trial registries. METHODS: We reviewed and analyzed all RCTs published in December 2014 with journals indexed in PubMed. The 2014 Impact Factors for the journals were used as proxies for their quality. RESULTS: Of the 451 analyzed papers, 58.1% reported an a priori sample size calculation. Nearly all papers provided the level of significance (97.7%) and desired power (96.6%), and most of the papers reported the minimum clinically important effect size (73.3%). The median (inter-quartile range) of the percentage difference of the reported and calculated sample size calculation was 0.0% (IQR -4.6%;3.0%). The accuracy of the reported sample size was better for studies published in journals that endorsed the CONSORT statement and journals with an impact factor. A total of 98 papers had provided targeted sample size on trial registries and about two-third of these papers (n=62) reported sample size calculation, but only 25 (40.3%) had no discrepancy with the reported number in the trial registries. CONCLUSIONS: The reporting of the sample size calculation in RCTs published in PubMed-indexed journals and trial registries were poor. The CONSORT statement should be more widely endorsed.

A new statistical model for the Day Reconstruction Method.

The Day Reconstruction Method (DRM) is a method to measure one's subjective affective status by soliciting information in a questionnaire about the previous day's activities. We developed a new model to examine the association of daily activities, the friendliness of interacting partners, and time-of-day on net affect scores among 10,377 adults participating in the World Health Organization's Study on global ageing and adult health (SAGE). A multilevel regression was fitted and the time-of-day effect was modeled by restricted cubic spline. The net affect score was a serpentine curve; stable from 4 a.m. to 6 a.m., increased from 7 a.m. to 12 noon, and became stable onwards. Participants had the highest net affect scores during religious activities (0.48, 95% confidence interval [CI]: 0.44, 0.53), and they enjoyed leisure activities, exercising, and household responsibilities more than work. Compared with events that lacked interacting partners, activities with very friendly interacting partners were associated with higher net affect scores (0.21, 95% CI: 0.19, 0.22), but events with slightly friendly interacting partners, slightly irritating or very irritating partners had lower net affect scores. To conclude, researchers using DRM for assessing well-being status across time should include the type of activities and the friendliness of the interacting partners.

Analogy motor learning by young children: a study of rope skipping.

Research in psychology suggests that provision of an instruction by analogy can enhance acquisition and understanding of knowledge. Limited research has been conducted to test this proposition in motor learning by children. The purpose of the present study was to examine the feasibility of analogy instructions in motor skill acquisition by children. Thirty-two children were randomly assigned to one of the two instruction protocols: analogy and explicit instruction protocols for a two-week rope skipping training. Each participant completed a pretest (Lesson 1), three practice sessions (Lesson 2-4), a posttest and a secondary task test (Lesson 5). Children in the analogy protocol displayed better rope skip performance than those in the explicit instruction protocol (p < .001). Moreover, a cognitive secondary task test indicated that children in the analogy protocol performed more effectively, whereas children in the explicit protocol displayed decrements in performance. Analogy learning may aid children to acquire complex motor skills, and have potential benefits related to reduced cognitive processing requirements.

Effect of Low-intensity Exercise on Physical and Cognitive Health in Older Adults: a Systematic Review.

BACKGROUND: It is well known that physical exercise is important to promote physical and cognitive health in older population. However, inconsistent research findings were shown regarding exercise intensity, particularly on whether low-intensity exercise (1.5 metabolic equivalent tasks (METs) to 3.0 METs) can improve physical and cognitive health of older adults. This systematic review aimed to fill this research gap. The objective of this study is to conduct a systematic review of the effectiveness of low-intensity exercise interventions on physical and cognitive health of older adults. METHODS: Published research was identified in various databases including CINAHL, MEDLINE, PEDro, PubMed, Science Direct, SPORTDiscus, and Web of Science. Research studies published from January 01, 1994 to February 01, 2015 were selected for examination. Studies were included if they were published in an academic peer-reviewed journal, published in English, conducted as randomized controlled trial (RCT) or quasi-experimental studies with appropriate comparison groups, targeted participants aged 65 or above, and prescribed with low-intensity exercise in at least one study arm. Two reviewers independently extracted the data (study, design, participants, intervention, and results) and assessed the quality of the selected studies. Fifteen studies met the inclusion criteria. Quality index ranged from 15 to 18 mean = 18.3 with a full score of 28, indicating a moderate quality. Most of the outcomes reported in these studied were lower limb muscle strength (n = 9), balancing (n = 7), flexibility (n = 4), and depressive symptoms (n = 3). RESULTS: Out of the 15 selected studies, 11 reported improvement in flexibility, balancing, lower limb muscle strength, or depressive symptoms by low-intensity exercises. CONCLUSIONS: The current literature suggests the effectiveness of low-intensity exercise on improved physical and cognitive health for older adults. It may be a desired intensity level in promoting health among older adults with better compliance, lower risk of injuries, and long-term sustainability.

Analogy instruction and speech performance under psychological stress.

To examine the efficacy of explicit and implicit forms of instruction for speech motor performance under conditions of psychological stress. In experiment 1, 20 participants were asked to deliver a formal presentation to validate the modified Trier Social Stress Test (TSST). In experiment 2, 40 participants were instructed explicitly by verbal explanation or implicitly by analogy to speak with minimum pitch variation and were subjected to psychological stress using the modified TSST. Acoustic correlates of pitch height (mean fundamental frequency) and pitch variation (standard deviation of fundamental frequency) significantly increased in experiment 1 when participants delivered a speech under modified TSST condition. In experiment 2, explicitly instructed participants were unable to maintain minimum pitch variation under psychological pressure caused by the modified TSST, whereas analogy-instructed participants maintained minimal pitch variation. The findings are consistent with existing evidence that analogy instructions may result in characteristics of implicit motor learning, such as greater stability of performance under pressure. Analogy instructions may therefore benefit speech motor performance and might provide a useful clinical tool for treatment of speech-disordered populations.