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Mitochondrial quality control processes are essential in governing mitochondrial integrity and function. The purpose of the study was to examine the effects of 10 weeks of high-intensity interval training (HIIT) on the regulatory protein machinery of skeletal muscle mitochondrial quality control and whole-body glucose homeostasis in diet-induced obese mice. Male C57BL/6 mice were assigned to low-fat diet (LFD) or high-fat diet (HFD) group. After 10 weeks, HFD-fed mice were divided into sedentary and HIIT (HFD + HIIT) groups for another 10 weeks (n = 9/group). Graded exercise test, glucose and insulin tolerance tests, mitochondrial respiration, and protein markers of mitochondrial quality control processes were determined. HFD-fed mice exhibited lower ADP-stimulated mitochondrial respiration (p < 0.05). However, 10 weeks of HIIT prevented this impairment (p < 0.05). Importantly, the ratio of Drp1(Ser616) over Drp1(Ser637) phosphorylation, an indicator of mitochondrial fission, was significantly higher in HFD-fed mice (p < 0.05), but such increase was attenuated in HFD-HIIT compared to HFD (-35.7%, p < 0.05). Regarding autophagy, skeletal muscle p62 content was lower in the HFD group than the LFD group (-35.1%, p < 0.05); however, such reduction was disappeared in the HFD + HIIT group. In addition, LC3B II/I ratio was higher in the HFD group than the LFD group (15.5%, p < 0.05) but was ameliorated in the HFD + HIIT group (-29.9%, p < 0.05). Overall, our study demonstrated that 10 weeks of HIIT was effective in improving skeletal muscle mitochondrial respiration and the regulatory protein machinery of mitochondrial quality control in diet-induced obese mice through the alterations of mitochondrial fission protein Drp1 phosphorylations and p62/LC3B-mediated regulatory machinery of autophagy.
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Treinamento Intervalado de Alta Intensidade , Resistência à Insulina , Masculino , Camundongos , Animais , Camundongos Obesos , Camundongos Endogâmicos C57BL , Músculo Esquelético/fisiologia , Dieta Hiperlipídica , Glucose/metabolismoRESUMO
OBJECTIVE: Dynamin-related protein 1 (Drp1) is the key regulator of mitochondrial fission. We and others have reported a strong correlation between enhanced Drp1 activity and impaired skeletal muscle insulin sensitivity. This study aimed to determine whether Drp1 directly regulates skeletal muscle insulin sensitivity and whole-body glucose homeostasis. METHODS: We employed tamoxifen-inducible skeletal muscle-specific heterozygous Drp1 knockout mice (mDrp1+/-). Male mDrp1+/- and wildtype (WT) mice were fed with either a high-fat diet (HFD) or low-fat diet (LFD) for four weeks, followed by tamoxifen injections for five consecutive days, and remained on their respective diet for another four weeks. In addition, we used primary human skeletal muscle cells (HSkMC) from lean, insulin-sensitive, and severely obese, insulin-resistant humans and transfected the cells with either a Drp1 shRNA (shDrp1) or scramble shRNA construct. Skeletal muscle and whole-body insulin sensitivity, skeletal muscle insulin signaling, mitochondrial network morphology, respiration, and H2O2 production were measured. RESULTS: Partial deletion of the Drp1 gene in skeletal muscle led to improved whole-body glucose tolerance and insulin sensitivity (P < 0.05) in diet-induced obese, insulin-resistant mice but not in lean mice. Analyses of mitochondrial structure and function revealed that the partial deletion of the Drp1 gene restored mitochondrial dynamics, improved mitochondrial morphology, and reduced mitochondrial Complex I- and II-derived H2O2 (P < 0.05) under the condition of diet-induced obesity. In addition, partial deletion of Drp1 in skeletal muscle resulted in elevated circulating FGF21 (P < 0.05) and in a trend towards increase of FGF21 expression in skeletal muscle tissue (P = 0.095). In primary myotubes derived from severely obese, insulin-resistant humans, ShRNA-induced-knockdown of Drp1 resulted in enhanced insulin signaling, insulin-stimulated glucose uptake and reduced cellular reactive oxygen species (ROS) content compared to the shScramble-treated myotubes from the same donors (P < 0.05). CONCLUSION: These data demonstrate that partial loss of skeletal muscle-specific Drp1 expression is sufficient to improve whole-body glucose homeostasis and insulin sensitivity under obese, insulin-resistant conditions, which may be, at least in part, due to reduced mitochondrial H2O2 production. In addition, our findings revealed divergent effects of Drp1 on whole-body metabolism under lean healthy or obese insulin-resistant conditions in mice.
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Resistência à Insulina , Animais , Humanos , Masculino , Camundongos , Dieta Hiperlipídica/efeitos adversos , Dinaminas/genética , Dinaminas/metabolismo , Glucose/metabolismo , Peróxido de Hidrogênio/metabolismo , Insulina/metabolismo , Resistência à Insulina/fisiologia , Camundongos Obesos , Músculo Esquelético/metabolismo , Obesidade/metabolismo , RNA Interferente Pequeno/metabolismo , Tamoxifeno/farmacologiaRESUMO
Mitochondrial quality control processes are essential in governing mitochondrial integrity and function. The purpose of the study was to examine the effects of 10 weeks of HIIT on the regulatory protein machinery of skeletal muscle mitochondrial quality control and whole-body glucose homeostasis in diet-induced obese mice. Male C57BL/6 mice were randomly assigned to a low-fat diet (LFD) or high-fat diet (HFD) group. After 10 weeks, HFD-fed mice were divided into sedentary and HIIT (HFD+HIIT) groups and remained on HFD for another 10 weeks (n=9/group). Graded exercise test, glucose and insulin tolerance tests, mitochondrial respiration and regulatory protein markers of mitochondrial quality control processes were determined by immunoblots. Ten weeks of HIIT enhanced ADP-stimulated mitochondrial respiration in diet-induced obese mice (P < 0.05) but did not improve whole-body insulin sensitivity. Importantly, the ratio of Drp1(Ser 616 ) over Drp1(Ser 637 ) phosphorylation, an indicator of mitochondrial fission, was attenuated in HFD-HIIT compared to HFD (-35.7%, P < 0.05). Regarding autophagy, skeletal muscle p62 content was lower in HFD group than LFD group (-35.1%, P < 0.05), however, such reduction was disappeared in HFD+HIIT group. In addition, LC3B II/I ratio was higher in HFD than LFD group (15.5%, P < 0.05) but was ameliorated in HFD+HIIT group (-29.9%, P < 0.05). Overall, our study demonstrated that 10 weeks of HIIT was effective in improving skeletal muscle mitochondrial respiration and the regulatory protein machinery of mitochondrial quality control in diet-induced obese mice through the alterations of mitochondrial fission protein Drp1 activity and p62/LC3B-mediated regulatory machinery of autophagy.
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BACKGROUND: Understanding fall circumstances can help researchers better identify causes of falls and develop effective and tailored fall prevention programs. This study aims to describe fall circumstances among older adults from quantitative data using conventional statistical approaches and qualitative analyses using a machine learning approach. METHODS: The MOBILIZE Boston Study enrolled 765 community-dwelling adults aged 70 years and older in Boston, MA. Occurrence and circumstances of falls (ie, locations, activities, and self-reported causes of falls) were recorded using monthly fall calendar postcards and fall follow-up interviews with open- and close-ended questions during a 4-year period. Descriptive analyses were used to summarize circumstances of falls. Natural language processing was used to analyze narrative responses from open-ended questions. RESULTS: During the 4-year follow-up, 490 participants (64%) had at least 1 fall. Among 1 829 falls, 965 falls occurred indoors and 804 falls occurred outdoors. Commonly reported activities when the fall occurred were walking (915, 50.0%), standing (175, 9.6%), and going down stairs (125, 6.8%). The most commonly reported causes of falls were slip or trip (943, 51.6%) and inappropriate footwear (444, 24.3%). Using qualitative data, we extracted more detailed information on locations and activities, and additional information on obstacles related to falls and commonly reported scenarios such as "lost my balance and fell." CONCLUSIONS: Self-reported fall circumstances provide important information on both intrinsic and extrinsic factors contributing to falls. Future studies are warranted to replicate our findings and optimize approaches to analyzing narrative data on fall circumstances in older adults.
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Vida Independente , Caminhada , Humanos , Idoso , Idoso de 80 Anos ou mais , Causalidade , Autorrelato , Fatores de RiscoRESUMO
Chronic musculoskeletal pain is prevalent and undertreated in older adults. In particular, multisite pain is associated with serious functional consequences and falls and appears to be a novel geriatric syndrome. The causes of multisite pain are often multifactorial, and emerging evidence supports a complex pathway whereby multisite pain leads to cognitive problems, mobility decline, fear of falling, falls, and reduced participation in life roles. A few pharmacologic approaches are safe and effective for older adults with chronic multisite pain and evidence for effectiveness of non-pharmacologic treatments for this common condition is very limited. Compared to light physical exercise, mind-body exercise may prove to be more beneficial for older adults living with chronic pain. Tai Chi, as a movement-based mind-body exercise, can relieve pain symptoms, improve cognition and physical function, and lower risk for falls in older adults. However, little is known about the potential benefits of Tai Chi for older adults with multisite pain syndrome. Future large-scale randomized-controlled trials are needed to investigate the effectiveness of Tai Chi in alleviating pain and lowering fall risk in older adults with multisite pain, and the biological mechanisms that underlie its potential benefits to chronic pain, physical and cognitive functions, and falls in this at-risk population.
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Dor Crônica , Tai Chi Chuan , Humanos , Idoso , Dor Crônica/terapia , Acidentes por Quedas/prevenção & controle , Medo/psicologia , Exercício FísicoRESUMO
BACKGROUND: Multisite musculoskeletal pain is highly prevalent among older adults yet undertreated. Studies support the promise of Tai Chi for managing pain and lowering fall risk. Since the COVID-19 pandemic, effective alternatives to classroom-based exercise programming are warranted. AIMS: To recruit 100 racially diverse older adults with multisite pain and increased fall risk, who are interested in participating in a future Tai Chi clinical trial, and to evaluate the feasibility and acceptability of a short-term, remotely delivered home-based Tai Chi program. METHODS: A random sample of adults aged 65 years or older living in diverse Boston neighborhoods were sent mailed invitations to participate in a telephone screening survey. Eligible adults were invited to join a 4-week Tai Chi program offered online via Zoom. Primary outcomes were class attendance, experience, and program safety. RESULTS: Among 334 survey respondents, 105 were eligible for the intervention. Average age of eligible participants was 74 years, 75% were women, and 62% were Black. We assigned 32 participants to 4 Tai Chi or 2 light exercise groups conducted via Zoom; of these, 24 (75%) completed the program and 79% attended ≥6 of 8 classes. There were no adverse events reported. Two-thirds reported it was very easy to join the online classes and 88%, very easy to see the instructor. CONCLUSION: Mailed invitations were effective for recruiting a racially diverse sample. Remote exercise programming delivered online via live Zoom sessions is safe and feasible for diverse older adults who have multisite pain and risk of falls.
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COVID-19 , Tai Chi Chuan , Humanos , Feminino , Idoso , Masculino , Projetos Piloto , Estudos de Viabilidade , Pandemias , COVID-19/terapia , DorRESUMO
Objectives: This study aims to determine domains of pain interference in daily routines assessed using the Brief Pain Inventory, in relation to multisite musculoskeletal pain among older adults living in the community. Design: The MOBILIZE Boston Study is a population-based study of 749 adults aged 70 and older. Measurements: Chronic musculoskeletal pain was assessed using a joint pain questionnaire and grouped as: no pain, single-site and multisite pain. The Brief Pain Inventory pain interference (PI) sub-scale assessed level of pain interference (0-10 rating) in 7 domains including general activity, mood, walking, work, relationships with people, sleep, and enjoyment of life. Interference ratings were grouped as: none (0), mild (>0 and ≤ 2), and moderate to severe (>2) PI. Results: PI was more common among women and those with less education compared to others. Older adults with chronic conditions such as osteoarthritis, depression, spinal stenosis, peripheral artery disease, and asthma/lung disease were more likely than their peers to report PI (p < 0.05). Multisite musculoskeletal pain was strongly associated with pain interference in all domains (p < 0.05). More than half of older adults with multisite musculoskeletal pain reported moderate to severe PI with general activity and walking. The highest prevalence of moderate to severe PI (score >2) in general activity was seen in participants with depression (62%), knee and hand osteoarthritis (71%) and peripheral artery disease (65%). Conclusion: Greater attention to PI and PI domains such as general activity and walking, could aid in efforts to reduce the overall impact of multisite musculoskeletal pain among older adults.
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BACKGROUND: Chronic pain is a risk factor contributing to mobility impairment and falls in older adults. Little is known about the patterns of circumstances of falls among older adults with chronicpain. OBJECTIVE: To examine the relationship between chronic pain and circumstances of falls including location, activities at the time of falls and self-reported causes of falls in older adults. DESIGN: Prospective cohort study. SETTING: Communities in/around Boston, Massachusetts. SUBJECTS: The MOBILIZE Boston Study enrolled 765 adults aged ≥70 years. METHODS: Pain severity, fall occurrence and fall circumstances were recorded using monthly calendar postcards and fall follow-up interviews during a 4-year follow-up period. Generalised estimating equation models were performed to examine the relation between monthly pain ratings and circumstances of the first fall in the subsequent month. RESULTS: Compared to fallers without chronic pain, fallers with moderate-to-severe pain had around twice the likelihood of reporting indoor falls (aOR = 1.93, 95%CI: 1.32-2.83), falls in living or dining rooms (aOR = 2.06, 95%CI: 1.27-3.36), and falls due to health problems (aOR = 2.08, 95%CI: 1.16-3.74) or feeling dizzy or faint (aOR = 2.10, 95%CI: 1.08-4.11), but they were less likely to report falls while going down stairs (aOR = 0.48, 95%CI: 0.27-0.87) or falls due to a slip or trip (aOR = 0.67, 95%CI: 0.47-0.95) in the subsequent month. CONCLUSIONS: Given the exploratory nature of the study, these findings should be interpreted with caution. Future studies may investigate whether better pain management and tailored fall prevention in older people with chronic pain could lead to fewer falls.
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Dor Crônica , Idoso , Boston/epidemiologia , Dor Crônica/diagnóstico , Dor Crônica/epidemiologia , Humanos , Estudos Prospectivos , Fatores de RiscoRESUMO
PURPOSE: To investigate the effects of different exercise components on physical function and mobility in adults after hip fracture. METHODS: Pubmed, Embase, Cochrane Library, Web of Science, CINAHL, and PsycINFO were searched up to March 2021. Randomized controlled trials investigating the effects of exercise interventions on physical function and mobility in adults after hip fracture were included. RESULTS: Fifteen studies (12 trials) were included (n = 1198, age = 80 ± 8 years). Exercise interventions had a moderate effect on overall physical function after hip fracture compared to non-exercise (SMD = 0.46, 95% CI = 0.27-0.65). Among different exercise components, progressive resistance exercise showed the largest effect (SMD = 0.48, 95% CI = 0.27-0.69), while aerobic exercise alone had no effect (SMD 0.41, 95% -0.44 to1.26) on physical function. Exercise had a small effect on mobility (SMD = 0.28, 95% CI = 0.12-0.43). Specifically, functional exercise showed a moderate effect (SMD = 0.41, 95% CI = 0.16-0.65) on mobility. CONCLUSIONS: Available evidence supports that exercise interventions improve physical function and mobility in older adults after hip fracture; specifically, resistance exercise with progressive load of 60-80% 1RM, and functional exercise may be critical intervention components respectively. Future high-quality research is needed to establish best practices. IMPLICATIONS FOR REHABILITATIONProgressive resistance exercise with 60-80% 1RM resulted in the largest improvement in physical function after hip fracture.Functional exercise appears to be a critical component for improving mobility after hip fracture. Functional exercise plus resistance and balance exercises was the most effective intervention for enhancing mobility.Exercise should be supervised by a trainer or a physiotherapist, and self-reported exercise may not result in the same benefits.
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Fraturas do Quadril , Idoso , Idoso de 80 Anos ou mais , Exercício Físico , Terapia por Exercício/métodos , HumanosRESUMO
Tai chi is known to improve balance and reduce falls in older adults. Yet, little is known about the impact of group tai chi on perceived social support and its relationship with participant self-efficacy and adherence. The current systematic review, guided by Social Cognitive Theory and Successful Aging, includes an overview of tai chi interventions with and without enhancements (e.g., music, mentorship, group practice) that evaluated social support among their outcomes (N = 10). PubMed, CINAHL, and PsycINFO databases were searched for studies eligible under the inclusion criteria: sample population aged ≥60 years and published between 1999 and 2019. Four articles reported on tai chi interventions with specific enhancements to promote social interaction and reported increased perceived social support (p < 0.05). Six studies evaluated social support outcomes of tai chi programs without specific modifications to promote social engagement. Four of the six traditional tai chi intervention studies reported improved social support (p < 0.05). Group tai chi interventions for older adults may increase social support and therefore further increase health benefits of tai chi exercise among this population. [Research in Gerontological Nursing, 14(3), 126-137.].
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Tai Chi Chuan , Idoso , Envelhecimento , Exercício Físico , Terapia por Exercício , Humanos , Apoio SocialRESUMO
This cross-sectional study examines the association between chronic musculoskeletal pain and foot reaction time (RT) among older community-living adults. Participants were 307 adults aged 71 years and older in the MOBILIZE Boston Study II. Pain severity, interference, and location were measured by the Brief Pain Inventory and a joint pain questionnaire. With participants seated, simple foot reaction time was measured as self-selected foot response time to an intermittent light, and choice foot reaction time was measured as response time to the light on the corresponding side of the sensored gait mat. We performed multivariable linear regression to determine associations of pain and foot RT, adjusted for sociodemographic and health characteristics, and serially adjusted for cognitive function (MMSE or Trail Making A). Pain severity and interference were associated with slower simple foot reaction time (P < .05). Pain severity and knee pain were associated with slower choice foot reaction time (P < .05). Adjustment for cognitive measures had little impact on the pain-RT relationship. This significant relationship was only observed among participants with less education. These results support the idea that chronic pain may lead to slower foot RT, thus could represent a fall hazard in older adults. Neuromotor mechanisms underlying the pain-fall relationship warrant further investigation. PERSPECTIVE: This study provides insights on the mechanisms underlying the pain-fall relationship. Chronic pain may contribute to slower foot RT thus increase fall risk in older adults. This may help inform interventions such as stepping training to reduce fall risk in older adults living with chronic pain.
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Acidentes por Quedas , Dor Crônica/fisiopatologia , Pé/fisiologia , Dor Musculoesquelética/fisiopatologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos/fisiologia , Estudos Transversais , Feminino , Humanos , Masculino , Medição da Dor , Índice de Gravidade de DoençaRESUMO
BACKGROUND: Given the evidence of the links between cognition and mobility, participation in cognitive activities may benefit neuromotor performance and mobility in older adults. AIMS: To examine the association between participation in cognitive activities and foot reaction time (RT) and gait speed in community-dwelling older adults. METHODS: The MOBILIZE Boston Study II (MBSII) re-enrolled 354 community-dwelling older adults aged ≥ 70 years from the original MBS cohort. Of these, 310 completed the performance testing and we excluded three participants who had Parkinson's disease. Cognitive Activities Scale (CAS) assessed participation in 17 cognitive activities. Simple and Choice foot RT (SRT, CRT, msec) and gait speed (m/s) were measured using a sensored GAITRite® gait mat. RESULTS: The average age of the 307 participants was 84 years; 79% were white and 65% were women. The average CAS score was 25.5 ± 11.7, indicating participation in approximately 26 activities per week on average. The average foot SRT was 245 ± 57msec and average CRT was 323 ± 85msec. Usual-paced gait speed was 0.9 ± 0.3 m/s on average. More frequent participation in cognitive activities was associated with shorter SRT (ß = - 0.759, p = 0.015) and CRT (ß = - 1.125, p = 0.013), and faster gait speed (ß = 0.003, p = 0.026), after adjusting for potential confounders. DISCUSSION: Participation in cognitively stimulating activities may be beneficial for neuromotor performance and mobility in older adults. CONCLUSIONS: Prospective and intervention studies are needed to determine whether participation in cognitive activities may prevent mobility decline over time, and thus reduce fall risk.
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Marcha , Velocidade de Caminhada , Idoso , Idoso de 80 Anos ou mais , Cognição , Feminino , Humanos , Estudos Prospectivos , Tempo de ReaçãoRESUMO
BACKGROUND: Fall injuries are a leading cause of death in older adults. The potential impact of chronic pain characteristics on risk for injurious falls is not well understood. This prospective cohort study examined the relationship between chronic pain and risk for injurious falls in older adults. METHOD: The MOBILIZE Boston Study enrolled 765 community-dwelling adults aged 70 years and older living in and around Boston, Massachusetts. Chronic pain characteristics, including pain severity, pain interference, and pain distribution, were measured at baseline using the Brief Pain Inventory subscales and a joint pain questionnaire. Occurrence of falls and fall-related injuries were recorded using monthly fall calendar postcards and fall follow-up interviews during the 4-year follow-up period. RESULTS: Negative binomial regression models showed that pain interference and pain distribution, but not pain severity, independently predicted injurious falls adjusting for potential confounders. Participants in the highest third of pain interference scores had a 61% greater risk of injurious falls compared to those reporting little or no pain interference. Compared to no pain, multisite pain was associated with a 57% greater risk of injurious falls. Stratified by gender, the association was only significant in women. In the short term, moderate-to-severe pain in a given month was associated with increased risk of injurious falls in the subsequent month. CONCLUSIONS: Global pain measures are associated with increased risk of injurious falls in older adults. Pain assessment should be incorporated into fall risk assessments. Interventions are needed to prevent fall injuries among elders with chronic pain.
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Dor Crônica , Vida Independente , Idoso , Idoso de 80 Anos ou mais , Dor Crônica/epidemiologia , Dor Crônica/etiologia , Feminino , Humanos , Estudos Prospectivos , Fatores de Risco , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Pain catastrophizing has been associated with pain intensity and mobility limitations in adults, and may be associated with mobility problems among older adults with chronic pain. This study examined the associations between pain catastrophizing and pain characteristics, and physical performance in older people. METHODS: The MOBILIZE Boston Study II (MBS) included 354 adults aged ≥70 years, living in the Boston area, originally enrolled in the MBS I from 2005-2008. Pain catastrophizing was measured using the 13-item Pain Catastrophizing Scale (PCS), with scores ranging from 13-65. Pain severity and pain interference were assessed by subscales of the Brief Pain Inventory. Pain distribution was classified as none, single site, and multisite. Mobility performance was assessed using the Short Physical Performance Battery (SPPB). Falls were assessed prospectively using monthly fall calendar postcards. RESULTS: One-fourth of all participants (24 %) had high scores on the PCS (score>30). PCS was inversely associated with age and was greater among those with osteoarthritis, depression, or anxiety (p-value<0.05). PCS score was associated with global measures of pain including pain severity (p-valueâ¯=â¯0.01), pain interference (p-valueâ¯=â¯0.004) and multisite pain compared to no pain (p-valueâ¯=â¯0.006). After adjusting for confounders, PCS was not associated with mobility and fall in this older population. CONCLUSION: Although pain catastrophizing is prevalent in older adults with chronic pain, it was not associated with mobility or falls in older people. Further research is needed to determine possible long-term effects of pain catastrophizing on chronic pain and functioning in older adults.
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Background: The validity and reliability of the Borg 6-20 rating of perceived exertion (RPE) scale has not been tested among Chinese people from Mainland China. The purpose of this study was to test: 1) The validity of Leung Chinese version and Wang Chinese version of the Borg 6-20 RPE scale; 2) The reliability of Wang Chinese version RPE scale; and 3) The agreement of these two Chinese versions of the RPE scale among young healthy adults from Mainland China. Methods: A total of 26 subjects (11 males, 15 females; age 22.7⯱â¯3.0â¯yrs) volunteered to participate. They performed one (nâ¯=â¯3), two (nâ¯=â¯14), or three trials (nâ¯=â¯9) of the Bruce treadmill protocol test within 9.0⯱â¯5.1 days (validation trials), and 30.4⯱â¯27.9 days (reliability trials). Power output, heart rate, oxygen consumption, and RPE were recorded. Results: RPE was significantly correlated with power output (Leung version rsâ¯≥â¯0.75, Wang version rsâ¯≥â¯0.73), heart rate (HR) (Leung version rsâ¯≥â¯0.84, Wang version rs â¯≥â¯0.87), and oxygen consumption (VO2) (Leung version rs â¯≥â¯0.80, Wang version rsâ¯≥â¯0.81) (all pâ¯<â¯0.01). The overall test-retest interclass correlation was 0.94 (pâ¯<â¯0.01). No significant differences in correlations (RPE against power output, HR and VO2) between trials existed for the reliability tests of Wang version scale. No significant differences in correlations (RPE against power output, HR and VO2) between the two Chinese versions of RPE scale existed. Conclusion: Both Chinese RPE scales are valid among young healthy Chinese mandarin speaking adults. The Wang scale is reliable, and the Leung and Wang scales show superior agreement with each other.
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This paper provides a literature review of current studies investigating the effects of meditation and mind-body exercise on peripheral concentrations of brain-derived neurotrophic factor (BDNF), an important mediator of the neuroplasticity of the central nervous system and cognitive function. A literature search was conducted to collect currently published randomized controlled, non-randomized controlled and uncontrolled intervention studies. Fifteen studies were identified; and among these studies, seven were randomized controlled studies, three were non-randomized studies, and five were uncontrolled studies. Current limited evidence tends to support that mindfulness meditation and mind-body exercise (e.g. yoga and tai chi) increase circulating BDNF concentrations in healthy and diseased individuals. It is noteworthy that these findings are based on current studies with a relatively small sample size, or without a randomized controlled design. Further studies are needed to identify a definite effect of meditation or mind-body exercise on BDNF and its role in improving/maintaining brain functions in various populations.
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PURPOSE: To test whether an 8-wk exergaming (EG) program would improve cognition and gait characteristics compared with a traditional physical exercise (TPE) program in older adults at risk for falling. METHODS: A pilot quasi-experimental study was conducted in adults age ≥65 yr at risk for falls, living in senior communities. Participants enrolled (n = 35) in either exercise program offered twice weekly for 8 wk. Cognition and single-task and dual-task gait characteristics were measured before and after the 8-wk exercise intervention. For each outcome, a repeated-measures ANCOVA adjusted for age, gender, and exercise intensity (ratings of perceived exertion, RPE) was used to examine the group-time interaction. RESULTS: Twenty-nine participants (age, 77 ± 7 yr) completed either the EG program (n = 15) or the TPE program (n = 14). Statistically significant group-time interactions were observed in Trail Making Test Part A (P < 0.05) and single-task gait speed, stride length, swing time percentage, and double support percentage (all P < 0.05), and marginal group differences were observed in Mini-Mental State Examination (P = 0.07), all favoring the EG program. There were no statistically significant group differences in dual-task gait measurements except for swing time percentage and double support percentage, favoring the EG program. CONCLUSIONS: An 8-wk EG program for older adults at risk for falls contributed to modest improvements in a number of cognitive measures and single-task but limited improvements in dual-task gait measures, compared with TPE. These findings support the need for larger trials to determine cognitive and mobility benefits related to EG.
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Acidentes por Quedas/prevenção & controle , Cognição/fisiologia , Exercício Físico/fisiologia , Exercício Físico/psicologia , Marcha/fisiologia , Jogos Recreativos/psicologia , Jogos de Vídeo/psicologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Percepção/fisiologia , Esforço Físico/fisiologia , Projetos Piloto , Fatores de RiscoRESUMO
The purpose of this exploratory study was to examine the effects of Tai Chi on blood levels of beta endorphin (ß-endorphin) and inflammatory markers in older adults with chronic pain. Forty community-dwelling older adults with chronic pain were randomized to Tai Chi or light physical exercise, and each offered twice weekly for 12 weeks. Following the 12-week intervention, neither Tai Chi nor light physical exercise changed levels of ß-endorphin and inflammatory markers. However, in older adults who completed 70% or more classes, Tai Chi significantly lowered levels of ß-endorphin (p < 0.05), whereas light physical exercise did not change levels of ß-endorphin. The results suggest that Tai Chi may reduce levels of ß-endorphin in older adults with chronic pain. Future studies are needed to better understand the role of the opioid analgesic system and immune system in regulating pain with aging and the long-term effects of Tai Chi on pain-related biomarkers.
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Dor Crônica/terapia , Tai Chi Chuan , beta-Endorfina/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Exercício Físico , Feminino , Humanos , Vida Independente , Inflamação , MasculinoRESUMO
BACKGROUND: Exergaming has the potential to improve physical function, cognition and dual-task function, and could be an effective new strategy for reducing risk of falling in older adults. OBJECTIVE: To evaluate and test custom Microsoft Kinect-based motion-tracking exergames in older adults at risk for falls. METHODS: Community-dwelling older adults who reported mobility difficulties or had fallen in the past year played three newly developed exergames (Target Trackers, Double Decision, and Visual Sweeps, 5 minutes each) in random order. Heart rate (HR) was measured during, and blood pressures (BPs), rating of perceived exertion (RPE), and rating of the enjoyment were recorded immediately after each exergame. RESULTS: Seven participants (median age 75 y; 4 females) completed the study. There were no adverse events reported during the exergaming session. Exercise HRs and RPEs were statistically significantly higher than resting for all exergames (p< 0.05). The differences were not significant for BPs. Enjoyment ratings ranged from 79.6-90.6% and there were no statistically significant differences between the exergames. CONCLUSIONS: The newly developed exergames were light in exercise intensity and enjoyable for older adults at risk for falls. Future intervention studies are warranted to examine the benefits of exergames for this special population.