Chronic effects of stretching on range of motion with consideration of potential moderating variables:A systematic review with meta-analysis

Background:It is well known that stretch training can induce prolonged increases in joint range of motion(ROM).However,to date more information is needed regarding which training variables might have greater influence on improvements in flexibility.Thus,the purpose of this metaanalysis was to investigate the effects of stretch training on ROM in healthy participants by considering potential moderating variables,such as stretching technique,intensity,duration,frequency,and muscles stretched,as well as sex-specific,age-specific,and/or trained state-specific adaptations to stretch training.Methods:We searched through PubMed,Scopus,Web of Science,and SportDiscus to find eligible studies and,finally,assessed the results from 77 studies and 186 effect sizes by applying a random-effect meta-analysis.Moreover,by applying a mixed-effect model,we performed the respective subgroup analyses.To find potential relationships between stretch duration or age and effect sizes,we performed a meta-regression.Results:We found a significant overall effect,indicating that stretch training can increase ROM with a moderate effect compared to the controls(effect size=-1.002;Z=-12.074;95%confidence interval:-1.165 to-0.840;p<0.001;I^(2)=74.97).Subgroup analysis showed a significant difference between the stretching techniques(p=0.01)indicating that proprioceptive neuromuscular facilitation and static stretching produced greater ROM than did ballistic/dynamic stretching.Moreover,there was a significant effect between the sexes(p=0.04),indicating that females showed higher gains in ROM compared to males.However,further moderating analysis showed no significant relation or difference.Conclusion:When the goal is to maximize ROM in the long term,proprioceptive neuromuscular facilitation or static stretching,rather than ballistic/dynamic stretching,should be applied.Something to consider in future research as well as sports practice is that neither volume,intensity,nor frequency of stretching were found to play a significant role in ROM yields.

Foam rolling and stretching do not provide superior acute flexibility and stiffness improvements compared to any other warm-up intervention: A systematic review with meta-analysis

Background:Acute improvement in range of motion(ROM)is a widely reported effect of stretching and foam rolling,which is commonly explained by changes in pain threshold and/or musculotendinous stiffness.Interestingly,these effects were also reported in response to various other active and passive interventions that induce responses such as enhanced muscle temperature.Therefore,we hypothesized that acute ROM enhancements could be induced by a wide variety of interventions other than stretching or foam rolling that promote an increase in muscle temperature.Methods:After a systematic search in PubMed,Web of Science,and SPORTDiscus databases,38 studies comparing the effects of stretching and foam rolling with several other interventions on ROM and passive properties were included.These studies had 1134 participants in total,and the data analysis resulted in 140 effect sizes(ESs).ES calculations were performed using robust variance estimation model with R-package.Results:Study quality of the included studies was classified as fair(PEDro score=4.58)with low to moderate certainty of evidence.Results showed no significant differences in ROM(ES=0.01,p=0.88),stiffness(ES=0.09,p=0.67),or passive peak torque(ES=-0.30,p=0.14)between stretching or foam rolling and the other identified activities.Funnel plots revealed no publication bias.Conclusion:Based on current literature,our results challenge the established view on stretching and foam rolling as a recommended component of warm-up programs.The lack of significant difference between interventions suggests there is no need to emphasize stretching or foam rolling to induce acute ROM,passive peak torque increases,or stiffness reductions.

Effects of Tai Ji Quan training on gait kinematics in older Chinese women with knee osteoarthritis: A randomized controlled trial

Background: Although Tai Ji Quan has been shown to relieve pain and improve functional mobility in people with knee osteoarthritis(OA), little is known about its potential benefits on gait characteristics among older Chinese women who have a high prevalence of both radiographic and symptomatic knee OA. This study aims to assess the efficacy of a tailored Tai Ji Quan intervention on gait kinematics for older Chinese women with knee OA.Methods: A randomized controlled trial involving 46 older women in Shanghai, China, with clinically diagnosed knee OA. Randomized(1:1)participants received either a 60 min Tai Ji Quan session(n = 23) 3 times weekly or a 60 min bi-weekly educational session(n = 23) for 24 weeks.Primary outcomes were changes in gait kinematic measures from baseline to 24 weeks. Secondary outcomes included changes in scores on the Western Ontario and Mc Master University Osteoarthritis Index(WOMAC) and Short Physical Performance Battery(SPPB).Results: After 24 weeks the Tai Ji Quan group demonstrated better performance in gait velocity(mean difference, 8.40 cm/s, p = 0.01), step length(mean difference, 3.52 cm, p = 0.004), initial contact angle(mean difference, 2.19°, p = 0.01), and maximal angle(mean difference, 2.61°,p = 0.003) of flexed knees during stance phase compared to the control group. In addition, the Tai Ji Quan group showed significant improvement in WOMAC scores(p < 0.01)(mean difference,-4.22 points in pain, p = 0.002;-2.41 points in stiffness, p < 0.001;-11.04 points in physical function, p = 0.006) and SPPB scores(mean difference, 1.22 points, p < 0.001).Conclusion: Among older Chinese women with knee OA, a tailored Tai Ji Quan intervention improved gait outcomes. The intervention also improved overall function as indexed by the WOMAC and SPPB. These results support the use of Tai Ji Quan for older Chinese adults with knee OA to both improve their functional mobility and reduce pain symptomatology.

Canadian Agility and Movement Skill Assessment(CAMSA):Validity, objectivity, and reliability evidence for children 8–12 years of age

Purpose: The primary aim of this study was to develop an assessment of the fundamental, combined, and complex movement skills required to support childhood physical literacy. The secondary aim was to establish the feasibility, objectivity, and reliability evidence for the assessment.Methods: An expert advisory group recommended a course format for the assessment that would require children to complete a series of dynamic movement skills. Criterion-referenced skill performance and completion time were the recommended forms of evaluation. Children, 8–12 years of age, self-reported their age and gender and then completed the study assessments while attending local schools or day camps. Face validity was previously established through a Delphi expert(n = 19, 21% female) review process. Convergent validity was evaluated by age and gender associations with assessment performance. Inter-and intra-rater(n = 53, 34% female) objectivity and test–retest(n = 60, 47% female) reliability were assessed through repeated test administration.Results: Median total score was 21 of 28 points(range 5–28). Median completion time was 17 s. Total scores were feasible for all 995 children who self-reported age and gender. Total score did not differ between inside and outside environments(95% confidence interval(CI) of difference:-0.7 to 0.6;p = 0.91) or with/without footwear(95%CI of difference:-2.5 to 1.9; p = 0.77). Older age(p < 0.001, η2= 0.15) and male gender(p < 0.001, η2= 0.02)were associated with a higher total score. Inter-rater objectivity evidence was excellent(intraclass correlation coefficient(ICC) = 0.99) for completion time and substantial for skill score(ICC = 0.69) for 104 attempts by 53 children(34% female). Intra-rater objectivity was moderate(ICC = 0.52) for skill score and excellent for completion time(ICC = 0.99). Reliability was excellent for completion time over a short(2–4 days; ICC = 0.84) or long(8–14days; ICC = 0.82) interval. Skill score reliability was moderate(ICC = 0.46) over a short interval, and substantial(ICC = 0.74) over a long interval.Conclusion: The Canadian Agility and Movement Skill Assessment is a feasible measure of selected fundamental, complex and combined movement skills, which are an important building block for childhood physical literacy. Moderate-to-excellent objectivity was demonstrated for children 8–12 years of age. Test–retest reliability has been established over an interval of at least 1 week. The time and skill scores can be accurately estimated by 1 trained examiner.

Parents' participation in physical activity predicts maintenance of some,but not all, types of physical activity in offspring during early adolescence:A prospective longitudinal study

Purpose: We aimed to examine the longitudinal associations between parents' and youth's participation in physical activity(PA).Methods-: One hundred and ninety youth cuompleted self-admitiistered questionnaires 3 times per year from 2011 to 2015, and their parents completed an interviewer-administered questionnaire during a telephone interview once in2011-2012. Data on youth's and parents' activities were classified as interdependent or coactive/imdependent.Results: Youth with one or both parents who participated in interdependent activities were more likely to maintain participation in interdependent activities(hazard ratio(HR) = 3.63: 95% confidence interval(CI) = 1.30-10.17). Youth's sustained participation in coactive/independent activities was not associated with parents' participation in coactive/independent activities(HR= 0.97; 95%CI=0.46-2.06).Conclusion: Longitudinal associations between parents' and youth's participation in PA differed across type of PA. Encouraging parents' participation in interdependent activities may promote sustained participation in interdependent activities in youth.

Surface Electromyographic Study of Peroneus Longus Activation during Ankle Eversion and Heel Lift

Prophylactic and rehabilitative ankle training programs rarely incorporate ankle eversion exercises of the weight bearing leg during one-legged stand. Such training may be necessary for the optimal PL function and dynamic ankle control. In this study, we compared a PL exercise that involved eversion of the inverted ankle of a weight bearing leg against the heel lift (HL), a popular PL strengthening exercise. The PL activation patterns were studied in 20 university students (7 male and 13 female). The self-reported dominant legs of the subjects were tested in this study. After recording the surface electromyographic (EMG) activity level of their PL maximal voluntary isometric contractions (MVIC), the subjects performed HL, and ankle eversions of the weight bearing ankle during one-legged stand. Ankle eversions were initiated from two inverted ankle positions, 20 degree inversion (EV1) and 25 degree inversion (EV2). The ankle position and the PL muscle activity were recorded with an accelerometer affixed to the dorsum of the foot and a surface EMG electrode over PL respectively. The ranges of motion for HL, EV1, and EV2 were 25, 29, and 31 degrees respectively. Expressed as percentage of MVIC, the average normalized EMG linear envelopes for EV1 (73%) and EV2 (74%) were significantly greater than HL (64%). These results demonstrated that eversions of the inverted ankle of the weight bearing leg elicited stronger PL activation that may result in better lateral ankle strength and dynamic control. Incorporation of weight bearing ankle eversions may enhance effectiveness of PL exercise and balance.

Adaptation of the Feedforward Postural Response to Repeated Continuous Postural Perturbations

We examined the adaptation of the postural response to repeated predictable platform oscillations. Our main goals were to determine whether the short-term changes that occurred during a minute long continuous postural perturbation trial were maintained in subsequent trials and to determine how many trials were required before participants fully adapted to the postural task. Ten participants performed ten minute-long postural trials on a platform that oscillated at 0.25 Hz before increasing to 0.50 Hz half way through each trial. Postural muscle onset latencies, burst amplitudes, and anterior posterior displacements of the center of pressure (COP) and center of mass (COM) were calculated for the last five cycles performed in each trial at 0.50 Hz. The postural strategy evolved in two phases: 1) immediate decrease in COP displacement;2) earlier activation of the postural muscles with smaller muscle burst amplitudes. After seven trials the postural response remained consistent.

有鞋带跑鞋和松紧鞋舌跑鞋跑步主观舒适度、足底压力和后足运动参数比较

目的:比较穿着鞋带跑鞋和采用松紧鞋舌跑鞋在主观舒适度、足底压力分布和后足运动参数方面的区别。方法:15名有经验的跑步者自愿参与本研究。采用一份可靠的问卷进行主观舒适度调查;采用Novel pedar足底压力测试系统记录受试者穿着两种跑鞋跑步时的足底压力分布;采用二维高速摄像系统和Ariel动作解析系统记录、分析受试者穿着两种跑鞋跑步时后足的运动图像及足跟相对小腿的内、外翻参数。结果:与穿着有鞋带跑鞋比较,受试者在穿着松紧鞋舌跑鞋跑步时的主观舒适度较差,第4和第5跖趾关节分区足底压强明显增加,后足外翻角度较大。结论:松紧鞋舌式设计并不适用于跑鞋。有鞋带跑鞋合脚性更好,可以帮助跑步者固定鞋内的脚。

中国青春期前男性肥胖儿童步态和姿势控制变化

目的：研究中国青春期前BMI（体重指数）小于30kg／m^2的男性肥胖儿童和体重正常的男性儿童在步态和姿势控制方面是否存在差别。方法：采用横向比较性研究设计。53名7～12岁中国天津地区男性儿童自愿参加测试，其中肥胖儿童27名（BMI为25．14±3．51kg／m^2），体重正常儿童26名（BMI为16．28±1．45kg／m^2）。采用平面动作解析方法分析受试者在正常、较慢和较快三种步频条件下的步态。采用足底压力中心转移评价受试者在不同视力条件（睁眼和闭眼）和不同站立姿势（双脚站立和双脚前后站立）时的姿势控制变化。结果：在三种步频条件下，肥胖儿童的站立期和双支撑期在一个步态周期中的比例均明显增加。在以不同姿势、不同视力条件站立时，肥胖儿童在其前后和左右方向上均以较慢的转移速度及较小平均位移距离进行姿势调节；在闭眼双脚站立情况下，肥胖儿童在左右方向上的位移变异量和转移范围均较正常儿童明显增加，压力中心（COP）转移面积明显增大；在闭眼前后脚站立情况下，肥胖儿童在左右方向上的位移变异量增加，COP转移面积增大。结论：与正常体重儿童比较，肥胖儿童的步态和姿势控制发生了明显变化。在视力被屏蔽时，左右方向上肥胖儿童与正常儿童比较COP位移变异量和转移范围变化更为明显。BMI小于30kg／m^2的中国青春期前男性肥胖儿童姿势控制能力下降。

步态终止对身体姿势稳定性影响研究

步行是一个周期性的重复过程,其基本要求是身体保持平衡并完成位置移动,可分为三个阶段：步态启动阶段、中间的双足交替移动阶段和步态终止阶段,这三个阶段是一个连贯不可分割的整体。步行过程中任何一个阶段的改变都有可能影响身体姿势的稳定.

儿童背不同质量书包步态终止时动力学分析

目的了解儿童步态终止时动力学特征,比较有计划步态终止(planned gait termination,PGT)和急停(unplanned gait termination,UPGT)时的差异,以及书包质量对儿童步态终止的影响。方法通过室内模拟步态终止发生场景,经两个三维测力台记录12名男孩(年龄(9.85±1.34)岁,身高(140.89±11.57)cm,体重(34.96±9.62)kg)背不同质量书包完成PGT和UPGT过程中地面反作用力及足底压力中心(center of pressure,COP)位移变化。结果 PGT和UPGT过程中地面反作用力曲线与行进中步态有明显差异,地面反作用力峰值和COP偏移均显著大于行进中步态,且差异随书包质量增加而增大,背15%体重(15%BW)书包急停时最大。结论儿童在步态终止时地面反作用力趋向有利于完成步态终止的方向变化,但身体所受冲击力可能随之增大,且随书包质量增加而增大;步态终止时控制姿势平衡的难度加大。建议儿童宜减轻书包质量,可能有助预防突发干扰时发生意外损伤。

健康成年女性穿倒跟鞋和普通运动鞋行走时的运动学参数及下肢肌电比较

目的:比较受试者穿着倒跟运动鞋和普通运动鞋在跑台上行走时,躯干和下肢的运动学特征,以及躯干和下肢肌肉活动特征。方法:13名健康女大学生志愿受试者,分别穿着倒跟和普通两种运动鞋在测试跑台上以1.33 m/s的速度行走。采用摄像机和Ariel运动解析系统记录和分析矢状面的行走的运动学参数。采用BTS表面肌电系统采集和分析优势侧竖脊肌、腹直肌、股直肌、股二头肌、胫骨前肌和腓肠肌外侧头表面肌电。结果:与普通运动鞋相比,穿着倒跟鞋行走时,步频加快、步幅缩短;躯干和髋关节最大伸展角度、膝关节最大弯曲角度、踝关节支撑相的背屈角度以及踝关节关节活动范围显著增加(P<0.05);胫骨前肌、腓肠肌的外侧头和股二头肌积分肌电、肌肉激活时间和平均振幅显著增加(P<0.05)。结论:穿着倒跟鞋行走改变了躯干和下肢的运动学特征,并增加下肢胫骨前肌、腓肠肌外侧头和股二头肌的活动。

长期太极拳和慢跑锻炼对侧向突发干扰下老年男性神经肌肉反应时和肌电达峰值时间影响

目的比较长期太极拳和慢跑锻炼对老年男性突发侧向姿势干扰下神经肌肉反应时和肌电达峰值时间的差异,探索提高老年男性侧向姿势挑战下神经肌肉反应和肌肉收缩效率的有效锻炼方式。方法利用足底水平干扰触发平台对年轻男性、无规律锻炼的老年男性、长期慢跑锻炼的老年男性、长期太极拳锻炼的老年男性进行突发侧向姿势干扰。表面肌电测试和分析系统用于收集腓骨长肌、胫骨前肌、臀中肌和竖脊肌的肌电信号。结果突发侧向干扰下,无规律锻炼老年男性腓骨长肌、胫骨前肌和臀中肌的神经肌肉反应时明显地慢于年轻男性,长期太极拳锻炼老年男性胫骨前肌和竖脊肌的神经肌肉反应明显地快于老年对照组;年轻男性腓骨长肌、胫骨前肌和臀中肌的收缩速度明显地快于3组老年人。结论长期太极拳锻炼可以使老年男性踝关节和躯干肌的神经肌肉反应更加迅速以应对侧向的姿势挑战,而对于提高老年男性肌肉收缩效率的效果不明显。

Exercise training improves participation in persons with multiple sclerosis:A systematic review and meta-analysis

Background Although previous studies have examined the effects of exercise training on other International Classification of Functioning,Disability and Health(ICF)component levels in persons with multiple sclerosis(MS),the effects of exercise training on participation remain unclear.The objectives of this review were to:(1)characterize systematically the use of outcome measures that capture participation in exercise training studies;(2)quantify the effect of exercise training on participation in persons with MS.Methods A search of 6 electronic databases(CINAHL,SPORTDiscuss,Embase,MEDLINE,Cochrane Central,and Scopus)was conducted to identify controlled and noncontrolled trials involving exercise training and participation in persons with MS.Search strings were built from Medical Subject Headings and CINAHL headings.ICF linking rules were used to identify participation chapters and categories captured.Meta-analysis was used to quantify the effect of exercise training on participation in randomized controlled trials comparing exercise effects to no intervention/usual care.Results We included 49 articles involving controlled and noncontrolled exercise trials in the systematic review of outcome measures.We captured 16 different outcome measures that captured all 9 participation chapters and identified 89 unique participation categories.Across these 16 outcome measures,mobility was the most commonly represented participation chapter,with 108 items.A subsample of 23 randomized controlled trials was included in the meta-analysis.An overall effect of 0.60(standard error=0.12,95%confidence interval:0.36-0.84,z=4.9,p<0.001)was calculated,indicating a moderate,positive effect of exercise training on participation.Conclusion The current review provides information that can be used to guide the selection of outcome measures that capture participation in studies of exercise training in persons with MS.Exercise training has a positive effect on outcomes that capture participation,providing further evidence for the role of exercise training in promoting and maintaining engagement in everyday life.

Exercise is...?: A commentary response

In the recent issue of Journal of Sport Health and Science,the question of'Is exercise medicine or what?'was posed.We wish to follow the editors’suggestion to'...stimulate further discussion on the topic'1by offering additional points of consideration to those discussed by Nesti2in'Exercise for health:Serious fun for the whole person?'.We will specifically

Effects of body mass and sex on kinematics and kinetics of the lower extremity during stair ascent and descent in older adults

The effects of body mass and sex on lower limb biomechanics during ascent and descent were examined in participants aged 50 to 75 with normal weight(n=19),overweight(n=18),and obese(n=8).Peak joint angles and joint moment of the lower limb were analyzed with the VICON motion analysis system.Results from multivariate analysis of variance showed that during descent,the overweight participants had significantly higher knee extensor moment(0.98±0.30 N·m/kg^(-1))than the normal-weight participants(0.70±0.29 N·m/kg^(-1)).The obese group had significantly higher ankle abductor moment(0.21±0.11 N·m/kg^(-1))than the normal weight(0.12±0.08 N·m/kg^(-1))and overweight groups(0.09±0.06 N·m/kg^(-1)).During ascent,the obese participants had significant higher hip flexor moment(0.42±0.20 N·m/kg^(-1))than overweight participants(0.22±0.17 N·m/kg^(-1)).Significant sex differences were found in knee extension angles(4.2±3.4℃vs 7.0±3.3℃)during descent,plantar flexion angles during ascent(23.7±5.3℃vs 15.6±3.7℃)and descent(29.9±5.0℃vs 22.1±7.9℃),and ankle adduction angles(6.8±4.8℃vs 2.5±2.5℃)during ascent.It is concluded that body mass has significant impact on joint loading of lower limbs during stair walking.Being overweight and obese increased hip joint loading during ascent,and knee and ankle joint loading during descent in older adults.Sex difference in joint kinematics was presented during stair walking regardless of the body mass.

Exercise Blood Pressure Response and Cardiometabolic Risk Factors in Middle Aged Women: A MONET Group Study

Objective: To investigate if an exaggerated peak exercise systolic blood pressure (peak ESBP) is associated with alteration of cardiometabolic risk factors and predict future resting hypertension in middle aged women. Methods: Data analysis was performed in 95 healthy normotensive premeno-pausal women at baseline and 84 after 5-year follow-up (age, 49.9 ± 1.9 years;BMI, 23.3 ± 2.2 kg/m2;resting BP, 117/73 ± 11.8/7.6 mmHg). Blood pressure was measured at rest and during a progressive exercise test on treadmill. Women were divided into two groups according to their peak ESBP <190 mmHg vs. ≥190 mmHg. Other outcome measures were: cardiorespiratory fitness (VO2 peak), body composition, body fat distribution and fasting plasma lipids, glucose and insulin levels. Results: 15% and 27% of women presented an exaggerated peak ESBP response (≥190 mmHg) at baseline and year 5 respectively. Linear mixed model repeated measures analysis revealed higher values of fasting glucose, resting systolic and diastolic BP in women with an exaggerated peak ESBP (≥190 mmHg) compared to women with a peak ESBP (<190 mmHg). No significant difference was observed between the two groups for VO2 peak, body composition and body fat distribution indices and other cardiometabolic risk factors. Finally, baseline peak ESBP was not a significant risk factor for future resting hypertension (OR: 2.96, 95%CI [0.48 - 18.12];P = 0.24). Conclusion: Our results, despite being non significant, are of great interest because in healthy and active premenopausal women, exaggerated peak ESBP is not predictive of future hypertension after 5-year follow-up throughout menopause transition.

Unequal aging in Nigeria: evidence on pre-COVID 19

Background:The study is focused on assessing predictors of later life inequality in Nigeria with specificity to the gaps in dimension and distribution.Methods:The study employed linear mixed multi-level regression analysis to assess predictors of aged inequalities status nested between geo-political zones and households.The study utilized the general household Survey-Panel(2018-2019)dataset(n=5527 persons aged≤60).Results:Evidence from the cross-sectional study revealed that aging inequalities are prevalent and persist between geo-political zones(γ00=1.374;p<0.001)and among households(γ00=1.266;p≤0.001).Demographic,social,and economic factors were strong determinants of inequality in the country.Conclusion:These results show that inequality among older adults in place and space is prevalent.Furthermore,these dire statistics of unequal inequalities at a later age are a significant problem in Nigeria.Therefore,an in-depth evaluation of the determined risk factors related to unequal aging and actions for its prevention are warranted.

Effects of a 12-week online Tai Chi intervention on gait and postural stability in individuals with Parkinson’s disease

Parkinson's disease(PD)affects gait and postural stability.Tai Chi(TC)is recommended for PD for management of the condition,however biomechanical understanding to its effects on gait and postural stability is limited.This study aimed to examine the effects of an online 12-week biomechanical-based TC intervention on gait and posture in people with PD.Fifteen individuals in early-stage PD were recruited(Hoehn&Yahr stages 1-2).The TC intervention program was 60min session,three times weekly for 12 weeks.The pre-and post-intervention test in obstacle crossing,timed-up-and-go(TUG)test,and single leg standing(SLS)with eyes open(EO)and closed(EC)were conducted.Gait speed,crossing stride length,clearance height of the heel and toe,anterior-posterior(AP)and medial-lateral(ML)displacement and velocity of the center of mass(COM)and separation of the COM-center of pressure(COP)were analyzed.The participants significantly improved their pre-vs.post-TC intervention performance on TUG test(p=0.002).During obstacle crossing,the participants significantly increased crossing stride length of the trailing foot,increased AP COM displacement and decreased ML COM-COP separation(p<0.05);the maximal dorsiflexion angle of the leading limb significantly increased and maximal plantarflexion angle of the trailing limb significantly decreased(p<0.05).A 12-week biomechanical-based online TC training was effective towards improvement of gait and postural stability among people in the early-stage of PD.The TC program and online training could be applied for management of PD.