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1.
Health Res Policy Syst ; 10: 14, 2012 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-22512780

RESUMO

BACKGROUND: Purpose of the study was to test a theoretical model to assess and develop policies for the promotion of physical activity among older people as part of an international intervention study. METHODS: 248 semi-standardized interviews with policy-makers were conducted in 15 European nations. The questionnaire assessed policy-makers' perceptions of organizational goals, resources, obligations, as well as organizational, political and public opportunities in the area of physical activity promotion among older people. In order to develop policies, workshops with policy-makers were conducted. Workshop outputs and outcomes were assessed for four nations nine months after the workshops. RESULTS: Policy assessment: Results of the policy assessment were diverse across nations and policy sectors. For example, organizational goals regarding actions for physical activity promotion were perceived as being most favorably by the sports sector. Organizational obligations for the development of such policies were perceived as being most favorably by the health sector. Policy development: The workshops resulted in different outputs: a national intersectoral action plan (United Kingdom), a national alliance (Sweden), an integrated policy (the Netherlands), and a continuing dialogue (Germany). CONCLUSIONS: Theory-driven policy assessment and policy-maker workshops might be an important means of scientific engagement in policy development for health promotion.


Assuntos
Exercício Físico , Política de Saúde , Promoção da Saúde/organização & administração , Formulação de Políticas , Idoso , Coleta de Dados , Europa (Continente) , Humanos , Cooperação Internacional , Objetivos Organizacionais , Política Organizacional , Inquéritos e Questionários
2.
Arch Phys Med Rehabil ; 92(2): 295-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21272727

RESUMO

OBJECTIVE: To determine the relationship between a measure of fatigue and 2 indices of physical fitness, lower limb extensor power (LLEP) and walking economy. DESIGN: This was a cross-sectional study of patients with stroke. Fatigue was assessed by vitality (VIT) score of the Medical Outcomes Study 36-Item Short-Form Health Survey version 2 (SF-36v2). LLEP of the unaffected limb was measured using a lower leg extensor power rig. Walking economy was calculated by measuring oxygen consumption (mL·kg(-1)·m(-1)) during walking at a comfortable speed. Bivariate analyses were performed relating VIT to indices of fitness. Multiple regression analyses were also performed and included age, sex, and either SF-36v2 emotional role function or SF-36v2 mental health, as predictors of VIT. SETTING: Community setting. PARTICIPANTS: Participants (N=66; 36 men; mean age ± SD, 71.0±9.9y) were all community dwelling, had survived a stroke, were able to walk independently, and had completed their stroke rehabilitation. INTERVENTIONS: Not applicable MAIN OUTCOME MEASURES: The main outcome measure is SF-36v2 (VIT), with walking economy and LLEP of the limb unaffected by the stroke being independent variables. RESULTS: Walking economy was not significantly related to VIT (R=-.024, P=.86, n=60). LLEP was positively related to VIT in bivariate analysis (R=.38, P=.003, n=58). After controlling for age, sex, and SF-36 emotional role function (or SF-36v2 mental health if the extreme outlier was excluded), LLEP remained a significant predictor of VIT. CONCLUSIONS: We found an association between fatigue and reduced LLEP. If a larger study confirms these findings, it would support the need to develop and test interventions to increase LLEP as a treatment for fatigue after stroke.


Assuntos
Fadiga/fisiopatologia , Aptidão Física/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Idoso , Estudos Transversais , Fadiga/etiologia , Fadiga/reabilitação , Feminino , Humanos , Extremidade Inferior/fisiopatologia , Masculino , Consumo de Oxigênio/fisiologia , Análise de Regressão , Fatores de Risco , Reabilitação do Acidente Vascular Cerebral , Inquéritos e Questionários , Caminhada/fisiologia
3.
Cochrane Database Syst Rev ; (4): CD003316, 2009 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-19821305

RESUMO

BACKGROUND: Physical fitness is low after stroke. It is unknown whether improving physical fitness after stroke reduces disability. OBJECTIVES: To determine whether fitness training (cardiorespiratory or strength, or both) after stroke reduces death, dependence and disability. The secondary aims were to determine the effects of fitness training on physical fitness, mobility, physical function, health status and quality of life, mood and incidence of adverse events. SEARCH STRATEGY: We searched the Cochrane Stroke Group Trials Register (last searched March 2009), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 1, 2007), MEDLINE (1966 to March 2007), EMBASE (1980 to March 2007), CINAHL (1982 to March 2007), and six additional databases to March 2007. We handsearched relevant journals and conference proceedings, and screened bibliographies. We searched trials registers and contacted experts in the field. SELECTION CRITERIA: We included randomised controlled trials if the aim of the intervention was to improve muscle strength or cardiorespiratory fitness, or both, and if the control groups comprised either no intervention, usual care or a non-exercise intervention. DATA COLLECTION AND ANALYSIS: Two review authors determined trial eligibility and quality. One review author extracted outcome data at end of intervention and follow-up scores, or as change from baseline scores. Diverse outcome measures limited the intended analysis. MAIN RESULTS: We included 24 trials, involving 1147 participants, comprising cardiorespiratory (11 trials, 692 participants), strength (four trials, 158 participants) and mixed training interventions (nine trials, 360 participants). Death was infrequent at the end of the intervention (1/1147) and follow up (8/627). No dependence data were reported. Diverse disability measures made meta-analysis difficult; the majority of effect sizes were not significant. Cardiorespiratory training involving walking, improved maximum walking speed (mean difference (MD) 6.47 metres per minute, 95% confidence interval (CI) 2.37 to 10.57), walking endurance (MD 38.9 metres per six minutes, 95% CI 14.3 to 63.5), and reduced dependence during walking (Functional Ambulation Categories MD 0.72, 95% CI 0.46 to 0.98). Current data include few strength training trials, and lack non-exercise attention controls, long-term training and follow up. AUTHORS' CONCLUSIONS: The effects of training on death, dependence and disability after stroke are unclear. There is sufficient evidence to incorporate cardiorespiratory training, involving walking, within post-stroke rehabilitation in order to improve speed, tolerance and independence during walking. Further trials are needed to determine the optimal exercise prescription after stroke and identify any long-term benefits.


Assuntos
Terapia por Exercício , Aptidão Física , Reabilitação do Acidente Vascular Cerebral , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Treinamento Resistido , Acidente Vascular Cerebral/mortalidade
4.
Can J Occup Ther ; 76(2): 73-80, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19456085

RESUMO

BACKGROUND: This study was set up to explore unexpected findings emergent from a randomized controlled trial of exercise versus relaxation post-stroke. PURPOSE: Stroke survivors' experiences of taking part in exercise and relaxation classes were explored. METHODS: In-depth, semi-structured interviews carried out with 14 community-dwelling stroke survivors in Edinburgh. The informants previously participated in a randomized exploratory trial of exercise versus relaxation. FINDINGS: The classes motivated participants to take part in other purposeful activities, to continue to practice what they had learned, and/or to attend another class in the community. Class participation also led to an improvement of self-perceived quality of life, specifically, improved confidence, physical ability, psychosocial functioning, and a sense of empowerment. IMPLICATIONS: Taking part in either exercise or relaxation classes after stroke can contribute to improved self-perceived quality of life, improved psychosocial functioning, and improved motivation to take an active role in the recovery process.


Assuntos
Terapia por Exercício , Terapia Ocupacional/métodos , Terapia de Relaxamento/psicologia , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/psicologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Motivação , Pesquisa Qualitativa , Qualidade de Vida , Características de Residência
5.
Arch Phys Med Rehabil ; 89(4): 677-83, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18373998

RESUMO

OBJECTIVE: To determine whether the explosive lower-limb extensor power of the affected and unaffected sides, and any asymmetry, are associated with activity limitations after stroke. DESIGN: Cross-sectional observational study of baseline data from a randomized controlled trial. SETTING: Measurements made in a hospital clinical research facility. PARTICIPANTS: Community-dwelling (N=66) subjects with stroke who were independently ambulatory. Subjects' mean age was 72+/-10 years. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The lower-limb extensor power of each lower limb (in W/kg), performance of specific functional activities (comfortable walking velocity, Functional Reach Test, chair-rise time, Timed Up & Go test), and global indices of activity limitation (FIM instrument, Rivermead Mobility Index, Nottingham Extended Activities of Daily Living). RESULTS: Low lower-limb extensor power in either lower limb was the principal factor from among the confounders we recorded that significantly (R(2) range, .21-.46) predicted the limitation of specific functional activities, and low lower-limb extensor power in either lower limb was the principal predictive factor for global indices of activity limitation (R(2) range, .13-.38). The degree of asymmetry of lower-limb extensor power between legs was low and had little or no predictive value. CONCLUSIONS: In ambulatory persons with stroke, activity limitations are associated with deficits in lower-limb extensor power of both lower limbs, and not the severity of any residual asymmetry. These findings suggest that interventions to increase lower-limb extensor power in both lower limbs might reduce activity limitations after stroke.


Assuntos
Terapia por Exercício/métodos , Contração Muscular/fisiologia , Reabilitação do Acidente Vascular Cerebral , Caminhada/fisiologia , Atividades Cotidianas , Idoso , Intervalos de Confiança , Estudos Transversais , Feminino , Seguimentos , Hemiplegia/diagnóstico , Hemiplegia/reabilitação , Humanos , Extremidade Inferior , Masculino , Pessoa de Meia-Idade , Limitação da Mobilidade , Debilidade Muscular/fisiopatologia , Músculo Esquelético/fisiologia , Probabilidade , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Acidente Vascular Cerebral/diagnóstico
6.
J Psychosom Res ; 63(5): 539-44, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17980228

RESUMO

OBJECTIVE: While fatigue after stroke is a common problem, it has no generally accepted definition. Our aim was to develop a case definition for post-stroke fatigue and to test its psychometric properties. METHODS: A case definition with face validity and an associated structured interview was constructed. After initial piloting, the feasibility, reliability (test-retest and inter-rater) and concurrent validity (in relation to four fatigue severity scales) were determined in 55 patients with stroke. RESULTS: All participating patients provided satisfactory answers to all the case definition probe questions demonstrating its feasibility For test-retest reliability, kappa was 0.78 (95% CI, 0.57-0.94, P<.01) and for inter-rater reliability kappa was 0.80 (95% CI, 0.62-0.99, P<.01). Patients fulfilling the case definition also had substantially higher fatigue scores on four fatigue severity scales (P<.001) indicating concurrent validity. CONCLUSION: The proposed case definition is feasible to administer and reliable in practice, and there is evidence of concurrent validity. It requires further evaluation in different settings.


Assuntos
Fadiga/etiologia , Acidente Vascular Cerebral/psicologia , Idoso , Idoso de 80 Anos ou mais , Fadiga/diagnóstico , Feminino , Humanos , Masculino , Índice de Gravidade de Doença
7.
J Am Geriatr Soc ; 55(6): 892-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17537090

RESUMO

OBJECTIVES: To determine the feasibility and effect of exercise training after stroke. DESIGN: Randomized exploratory trial comparing exercise training (including progressive endurance and resistance training) with relaxation (attention control). SETTING: Interventions were performed in a rehabilitation hospital. PARTICIPANTS: Sixty-six independently ambulatory patients (mean age 72, 36 men) without significant dysphasia, confusion, or medical contraindications to exercise training who had completed their usual rehabilitation and had been discharged from hospital. INTERVENTION: Both interventions were held three times a week for 12 weeks. Up to seven patients attended each session. MEASUREMENTS: The Functional Independence Measure; Nottingham Extended Activities of Daily Living; Rivermead Mobility Index; functional reach; sit-to-stand; elderly mobility score; timed up-and-go; Medical Outcomes Study 36-Item Short Form Questionnaire, version 2 (SF-36); Hospital Anxiety and Depression Score; aspects of physical fitness (comfortable walking speed, walking economy, and explosive leg extensor power) were measured at baseline, immediately after interventions (3 months), and 7 months after baseline. RESULTS: The median number of intervention sessions attended was 36 (interquartile range (IQR) 30.00-36.75) for exercise and 36 (IQR 30.50-37.00) for relaxation. Adherence to the individual exercises ranged from 94% to 99%. At 3 months, role-physical (an item in SF-36), timed up-and-go, and walking economy were significantly better in the exercise group (analysis of covariance). At 7 months, role-physical was the only significant difference between groups. CONCLUSION: Exercise training for ambulatory stroke patients was feasible and led to significantly greater benefits in aspects of physical function and perceived effect of physical health on daily life.


Assuntos
Terapia por Exercício , Reabilitação do Acidente Vascular Cerebral , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Atividade Motora/fisiologia , Cooperação do Paciente , Recuperação de Função Fisiológica/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/psicologia , Resultado do Tratamento
8.
Stroke ; 38(7): 2090-5, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17525397

RESUMO

BACKGROUND AND PURPOSE: There is little information on how to best measure poststroke fatigue. Our aim was to identify which currently available fatigue scale is most valid, feasible, and reliable in stroke patients. METHODS: Fatigue scales were identified by systematic search, and the 5 with the best face validity were identified by expert consensus. Feasibility (ie, did patients provide answers?) and internal consistency (an aspect of reliability) of these scales were evaluated by interviewing 55 stroke patients. Test-retest reliability was assessed by reinterviewing 51 patients, interrater reliability was assessed by rerating audio recordings, and convergent validity was assessed by measuring the correlation between scale scores. RESULTS: Of the 52 scales identified, the SF-36v2 (vitality component), the fatigue subscale of the Profile of Mood States, the Fatigue Assessment Scale, the general subscale of the Multidimensional Fatigue Symptom Inventory, and the Brief Fatigue Inventory had the best face validity. The Brief Fatigue Inventory was unfeasible to administer and was omitted. Of the remaining 4 scales, the Fatigue Assessment Scale had the poorest internal consistency. Test-retest reliability for individual scale questions ranged from fair to good; the Fatigue Assessment Scale had the narrowest limits of agreement for the total score, indicating the best test-retest reliability. Interrater reliability for individual questions ranged from good to very good, and there was no significant mean difference in total scores for any scale. Convergent validity was moderate to high for the total scores of the 4 scales. CONCLUSIONS: All four scales were valid and feasible to administer to stroke patients. The Fatigue Assessment Scale had the best test-retest reliability but the poorest internal consistency.


Assuntos
Fadiga/etiologia , Perfil de Impacto da Doença , Acidente Vascular Cerebral/complicações , Idoso , Idoso de 80 Anos ou mais , Avaliação da Deficiência , Estudos de Avaliação como Assunto , Fadiga/fisiopatologia , Humanos , Masculino , Reprodutibilidade dos Testes , Inquéritos e Questionários
9.
Eur J Appl Physiol ; 100(3): 355-62, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17429682

RESUMO

The objectives of this study were to (1) evaluate the suitability of "comfortable" self-paced walking as a mode of exercise to study VO(2) kinetics, and (2) to investigate VO(2) kinetics after hip fracture using self-paced walking as the exercise mode. The study took place in a Scottish rehabilitation hospital physiotherapy gymnasium [hip fracture (HF) group] and a Scottish University Gymnasium [young (Y) and healthy elderly (HE) groups]. Fifteen women after HF (median age 81 years) and five Y and five older HE women (median ages 22 and 78 years, respectively) took part in the study. Volunteers completed three repeats of 3 min of "comfortable" self-paced walking on two occasions. The ensemble averaged VO(2) response from walks 2 and 3 on visits 1 and 2 were combined and characterised using nonlinear regression techniques to derive a Mean Response Time (MRT). Self-paced walking was described as "constant-load" exercise (coefficient of variation of lap speeds of

Assuntos
Envelhecimento/fisiologia , Fraturas do Quadril , Consumo de Oxigênio/fisiologia , Caminhada/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Exercício Físico/fisiologia , Tolerância ao Exercício/fisiologia , Feminino , Humanos , Avaliação de Resultados em Cuidados de Saúde , Análise de Regressão
10.
Growth Horm IGF Res ; 16(5-6): 373-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17107821

RESUMO

CONTEXT: Little is known about the expression of skeletal muscle-specific isoforms of the insulin-like growth factor-I (IGF-I) gene in response to exercise in humans. Data for women are sparse and the influences of age and physical training status are unknown. Here we aimed to describe the expression of mRNA for the IGF-I isoforms in the quadriceps muscles of women at rest and after isometric exercise. OBJECTIVE: To categorize mRNA expression of the IGF-I splice variants IGF-IEa and IGF-IEc (MGF) in healthy women, determine whether isometric exercise stimulates expression, and to determine the duration of the response. DESIGN: Observational study. SETTING: Clinical research facility. PARTICIPANTS: Six healthy women (median age 38 years, range 25-43 years). INTERVENTION: Single bout of maximal isometric knee extension undertaken as 20 sets of 6 contractions. Muscle samples from the lateral mass of the quadriceps were obtained by needle biopsy at baseline, 2.5h and 50h after exercise. MAIN OUTCOME MEASURES: Quantification of mRNAs for IGF-IEa and MGF. RESULTS: mRNA for the IGF-IEa transcript was significantly elevated by 50h post-exercise compared to baseline (p=0.005) and mRNA for MGF was significantly elevated by 2.5h (p=0.026). There were no statistically significant differences between measurements at 2.5h and 50h for either transcript. CONCLUSIONS: We have shown that the upregulation of the muscle specific IGF-IEa and MGF isoforms occurs within 2.5h of a single bout of isometric exercise in women. The upregulation persists for at least 2 days after exercise. We have also demonstrated a potentially safe and effective way of studying the responsiveness of these isoforms to resistance exercise in future studies of older and/or frail individuals.


Assuntos
Exercício Físico/fisiologia , Fator de Crescimento Insulin-Like I/genética , Músculo Esquelético/metabolismo , Adulto , Processamento Alternativo , Feminino , Expressão Gênica , Humanos , Isoformas de Proteínas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Tempo
11.
Cerebrovasc Dis ; 21(3): 201-7, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16401884

RESUMO

BACKGROUND: Reduced mobility after stroke may cause a loss of muscle mass which may, in theory, contribute to disability. We investigated longitudinal changes in muscle strength, lean cross-sectional area and muscle mass in all limbs after acute stroke. METHODS: We recruited 17 patients within 72 h of hospital admission and measured (a) hand grip strength, (b) knee extensor strength and (c) arm and leg lean cross-sectional area on 6 occasions over 6 months. Appendicular and total muscle mass (dual-energy X-ray absorptiometry) were measured at 3 weeks and 6 months. RESULTS: There was no significant change over time in the strength, lean cross-sectional area and muscle mass of the arms or legs. We noted that muscle strength was substantially lower in all limbs compared with population norms. CONCLUSION: We found no evidence of a decline in muscle strength or mass in any limb after the stroke, which could have been attributed to reduced mobility. The observed muscle weakness in the ipsilateral side may have pre-dated the stroke.


Assuntos
Debilidade Muscular/fisiopatologia , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Atrofia Muscular/patologia , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/fisiopatologia , Absorciometria de Fóton , Idoso , Antropometria , Braço/fisiopatologia , Índice de Massa Corporal , Feminino , Força da Mão/fisiologia , Humanos , Contração Isométrica , Joelho/fisiopatologia , Perna (Membro)/fisiopatologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Limitação da Mobilidade , Contração Muscular , Debilidade Muscular/etiologia , Debilidade Muscular/patologia , Atrofia Muscular/etiologia , Atrofia Muscular/fisiopatologia , Acidente Vascular Cerebral/complicações
12.
J Aging Phys Act ; 13(2): 172-83, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15995263

RESUMO

This study examined the effect of age on descriptive walking-speed instructions commonly used in health promotion. Participants were 9 young (20-23 years) and 9 older (75-83 years) women. Oxygen uptake and walking speed were measured in response to descriptive walking instructions ("slow," "comfortable," "brisk," and "fast"). Although the older women walked approximately 20% slower in response to all walking instructions and with significantly lower oxygen costs for brisk and fast, the intensity of the exercise represented a much greater percentage of VO2max and showed greater interindividual variation. When asked to walk at a brisk pace, the older women averaged 67% VO2max (SD 20.6), whereas the young women averaged only 45% VO2max (SD 4.5). With older people, brisk might elicit an exercise intensity unnecessarily high for physiological benefit and that might compromise safety and adherence, which emphasizes the need for validation of carefully worded exercise and training guidance for older adults.


Assuntos
Comunicação , Promoção da Saúde , Caminhada , Idoso , Feminino , Humanos , Consumo de Oxigênio , Caminhada/fisiologia
15.
J Appl Physiol (1985) ; 95(6): 2544-53, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12937026

RESUMO

Cycling on a mechanically braked cycle ergometer was used as a novel approach to compare the effects of three different 16-wk resistance-training programs on isometric force, power output, and selected functional abilities in 31 healthy 65- to 74-yr-old women. Training was conducted three times per week. During each session, individuals of the speed group performed 8 sets of 16 pedal revolutions at 40% of the maximal resistance to complete two revolutions (2 RM); strength group performed 8 sets of 8 revolutions at 80% of 2 RM; and combination group performed 4 sets of 16 revolutions at 40% and 4 sets of 8 revolutions at 80% of 2 RM. During each set, all participants were required to pedal as fast as possible with a 2-min interval between sets. All training groups significantly increased force, power, and functional abilities (maximal treadmill walking speed, vertical jumping, and box stepping) at week 8 (in the range from 6.5 to 20.8%) with no further improvement at week 16 (except maximal treadmill walking speed), but no significant differences were observed between the three groups. The novel approach to performing both low- and high-resistance training, based on the use of a cycle ergometer, has been shown to be effective in improving strength, power, and functional abilities in a group of healthy women. Even fit older women can still improve in functional abilities. Interestingly, the "high-speed" and "low-speed" programs induced an increase in both power and strength of similar magnitude.


Assuntos
Ciclismo/fisiologia , Músculo Esquelético/fisiologia , Aptidão Física/fisiologia , Adaptação Fisiológica , Idoso , Eletromiografia , Teste de Esforço , Feminino , Humanos , Contração Isométrica/fisiologia , Perna (Membro)/anatomia & histologia , Perna (Membro)/fisiologia , Cooperação do Paciente , Segurança
16.
Med Sci Sports Exerc ; 34(7): 1199-206, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12131263

RESUMO

PURPOSE: To determine whether explosive power and isometric strength of the lower-limb muscles in elite master Olympic weightlifters declines at a similar rate to nontrained healthy controls with increasing age. METHODS: 54 elite level masters weightlifters (aged 40-87), who were competitors at the World Masters Weightlifting Championships (1999), were compared with a similar number of aged-matched, healthy untrained individuals. Isometric knee extensor strength and lower-limb explosive power were tested. Extent of antagonist co-contraction during isometric knee extension was determined by EMG and power loading characteristics by using a variable inertial system. Muscle volume was estimated using anthropometry. RESULTS: On average, the weightlifters were able to generate 32% more peak power (P < 0.05) in the lower limbs and 32% more isometric knee extensor force (P < 0.05) than the control subjects. No significant differences in lower-leg volume were observed between the two groups. Peak power declined at a similar rate with increasing age in the weightlifters and controls (1.2 and 1.3% of a 45-yr-old's value per year), as did strength, but at a lower rate (0.6 and 0.5% per year). The inertial load at which the weightlifters achieved their maximal peak power output was greater (P < 0.05) than the controls. The torque generated at this optimal inertia was also greater in the weightlifters (P < 0.05), whereas the time taken for the weightlifters to reach their maximal peak power was on average 13% shorter (P < 0.05). No differences in antagonist co-contraction during isometric knee extension were observed between the two groups. CONCLUSIONS: Muscle power and isometric strength decline at a similar rate with increasing age in elite master weightlifters and healthy controls. In spite of inertial load optimization, muscle power declined in both groups at approximately twice the rate of isometric strength. Although similar rates of decline were observed, the absolute differences between the weightlifters and controls were such that an 85-yr-old weightlifter was as powerful as a 65-yr-old control subject. This would therefore represent an apparent age advantage of approximately 20 yr for the weightlifters.


Assuntos
Contração Isométrica/fisiologia , Músculo Esquelético/fisiologia , Levantamento de Peso/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Eletromiografia , Humanos , Articulação do Joelho/fisiologia , Perna (Membro)/fisiologia , Masculino , Pessoa de Meia-Idade
17.
Age Ageing ; 31(4): 255-60, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12147562

RESUMO

OBJECTIVE: to determine the effects of aerobic training on the maximal aerobic power of healthy, very elderly people. DESIGN: a 12-week control period followed by 24 weeks of progressive, weight bearing, aerobic training. SUBJECTS: 26 men and women aged 79 to 91 years conforming to pre-determined health criteria. METHODS: we took measurements before and after a 12 week control period and following 24 weeks of training. These were maximal aerobic power (VO(2)max), heart rate at an oxygen consumption of 10 ml x kg(-1) x min(-1) (HR at VO(2)10), resting heart rate, isometric knee extensor strength, isometric elbow flexor strength and lower limb extensor power. MAIN RESULTS: pre-control values of VO(2)max for the women and men were 14.1 (SD 2.79) and 22.0 (5.12) ml.kg(-1).min(-1) respectively. There was no significant change in the VO(2)max of either group over the control period. After training, there was a 15% increase in the VO(2)max of the women (P<0.01) but no change was observed in the men. In the women, there was no significant change in HR at VO(2)10 over the control period but a 14% decrease (P<0.01) after training. In the men there was a 7% (P<0.05) increase in HR at VO(2)10 over the control period and a 5% (P<0.05) decrease after training. No effect of training was seen on isometric knee extensor strength, isometric elbow flexor strength or lower limb extensor power of either group. CONCLUSION: progressive aerobic training can increase the maximal aerobic power of very elderly women. A 15% increase in VO(2)max may prevent many elderly women from crossing functionally important thresholds, thereby helping to maintain independence.


Assuntos
Envelhecimento/fisiologia , Exercício Físico/fisiologia , Idoso , Idoso de 80 Anos ou mais , Peso Corporal , Feminino , Frequência Cardíaca , Humanos , Pulmão/fisiologia , Masculino , Contração Muscular , Consumo de Oxigênio , Fatores de Tempo
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