Jacqui Raymond

Efficacy of progressive resistance training on balance performance in older adults : a systematic review of randomized controlled trials.

The serious health, social and economic consequences of falls are well documented. Lower extremity muscle weakness and power as well as balance impairment are major independent intrinsic contributors to falls and amenable to intervention. Progressive resistance training (PRT) is widely accepted as an appropriate modality for treating sarcopenia and has been reported to improve balance. However, other studies affirm no significant effect of PRT on balance. To date, there is no clear, definitive statement or synthesis of studies that has examined the effect of PRT on balance. Therefore, our objective was to systematically review the literature to probe the merit of PRT as a single intervention on balance performance in older adults. We conducted a comprehensive search of major electronic databases to October 2006, with citation searches and bibliographic searches of journal articles and literature/systematic reviews. Two independent reviewers screened for eligibility and assessed the quality of the studies using the Physiotherapy Evidence Database scale for validity assessment. Randomized controlled trials of PRT only, with any balance outcome in participants with a mean age of ≥60 years (individual minimum age >50 years) were included. Trials that contained more than one intervention, providing the PRT and control groups matched the inclusion criteria, were also included. Because of the heterogeneity of interventions and balance outcomes, a meta-analysis was not performed. However, corrected effect sizes with confidence intervals were determined for each study outcome. Twenty-nine studies were compatible with the inclusion/exclusion criteria and were eligible for review. Participants (n = 2174) included healthy, community-dwelling, mobility-limited, frail cohorts and those with chronic comorbidities. Balance outcomes conducted were extensive and were broadly categorized by the authors as: static, dynamic, functional and computerized dynamic posturography. Some studies used more than one balance outcome. The number of balance tests in all totalled 68. Fourteen studies (15 tests representing 22% of all balance tests) reported improvements, significantly greater than controls, in balance performance following PRT. Improvements were not linked to a particular type of balance performance. The inconsistent effect of PRT on balance may be explained by heterogeneity of cohort and balance tests, variability in methodology of the balance test and sample size, inadequate dose of PRT and/or compliance to training, or lack of statistical power. Standardization of balance testing methodology and better reporting of procedures may ensure greater comparability of results in future studies. It is also possible that PRT alone is not a robust intervention for balance control. This is the first systematic synthesis of the literature to examine the effectiveness of PRT alone on balance performance in older adults. The limited evidence presented in currently published data has not consistently shown that the use of PRT in isolation improves balance in this population. However, further research should explore optimal resistance training regimens that: focus on the muscles most pertinent to balance control, best target neuromuscular adaptations that protect against postural challenges and elucidate mechanism(s) by which PRT may affect balance control.

Cardiorespiratory fitness and walking ability in subacute stroke patients.

OBJECTIVES To evaluate the cardiorespiratory fitness of subacute stroke patients and to determine whether reduced fitness is associated with gait performance. DESIGN Descriptive, cross-sectional study. SETTING Rehabilitation hospital. PARTICIPANTS Seventeen patients in an inpatient rehabilitation unit who had mild to moderate gait impairments after a recent (< or =7wk) stroke. All subjects could walk at least 3m alone or with an aid but with no standby assistance. INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Peak and submaximal cardiorespiratory responses were measured during semirecumbent leg cycling exercise. Walking velocity and endurance were assessed with 10-m and 6-minute walk tests, respectively. RESULTS Peak oxygen uptake (Vo(2)peak) was 1.15+/-0.36L/min, which was only 50% of the Vo(2)peak reported in the literature for a healthy, age-matched group. Maximal walking velocity (1.02+/-0.28m/s) and endurance (294.1+/-120.2m) were also approximately 50% of an aged-matched healthy group. Pearson product-moment correlations revealed that 6-minute walking endurance was strongly associated with self-selected walking velocity (R=.91) and measures of peak cardiorespiratory fitness (R=.84). CONCLUSIONS Cardiorespiratory fitness was markedly impaired within 7 weeks after a stroke. Although muscle weakness and loss of coordination are the primary impairments that affect gait after a stroke, impaired cardiorespiratory fitness may secondarily affect gait performance by limiting walking endurance. To address this secondary impairment, current rehabilitation interventions can incorporate assessment of cardiorespiratory fitness status and aerobic exercise training for persons after stroke.

Cardiorespiratory responses to arm cranking and electrical stimulation leg cycling in people with paraplegia

PURPOSE The purpose of this study was to assess the cardiorespiratory responses during arm exercise with and without concurrent electrical stimulation-induced leg cycling in people with paraplegia. METHODS On separate days, 10 subjects with spinal cord injuries (T5-T12) performed either arm cranking (ACE), or simultaneous arm cranking + electrical stimulation-induced leg cycling (ACE+ES-LCE) graded exercise tests. RESULTS During submaximal, steady-state exercise, ACE+ES-LCE elicited significantly higher VO2, (by 0.25-0.28 L x min(-1)) stroke volume (by 13 mL), and VE(BTPS) (by 9.4 L x min(-1)) compared with ACE alone. In contrast, there were no significant differences of submaximal HR, cardiac output, or power output between the exercise modes. At maximal exercise, ACE+ES-LCE elicited significantly higher VO2 (by 0.23 L x min(-1)) compared with ACE alone, but there were no differences in power output, HR, or VE(BTPS). CONCLUSIONS These results demonstrate that during submaximal or maximal exercise there was a greater metabolic stress elicited during ACE+ES-LCE compared with during ACE alone. The higher stroke volume observed during submaximal ACE+ES-LCE, in the absence of any difference in HR, implied a reduced venous pooling and higher cardiac volume loading during ACE+ES-LCE. These results suggest that training incorporating ACE+ES-LCE may be more effective in improving aerobic fitness in people with paraplegia than ACE alone.

Cardiovascular responses to an orthostatic challenge and electrical-stimulation-induced leg muscle contractions in individuals with paraplegia

Abstract The purpose of this study was to investigate the cardiovascular and haemodynamic responses that occur during moderate orthostatic challenge in people with paraplegia, and the effect of electrical stimulation (ES)-induced leg muscle contractions on their responses to orthostatic challenge. Eight males with complete spinal lesions between the 5th and 12th thoracic vertebrae (PARA) and eight able-bodied individuals (AB) volunteered for this study. Changes in heart rate (fc), stroke volume (SV), cardiac output (Q˙c), mean arterial pressure (MAP), total peripheral resistance (TPR), limb volumes and indices of neural modulation of fc, [parasympathetic (PNS) and sympathetic (SNS) nervous system indicators] were assessed during: (1) supine rest (REST), (2) REST with lower-body negative pressure at −30 torr (LBNP −30, where 1 torr = 133.32 N/m2), and (3) for PARA only, LBNP −30 with ES-induced leg muscle contractions (LBNP + ES). LBNP −30 elicited a decrease in SV (by 23% and 22%), Q˙c (by 15% and 18%) and the PNS indicator, but an increase in fc (by 10% and 9%), TPR (by 23% and 17%) and calf volume (by 1.51% and 4.04%) in both PARA and AB subjects, respectively. The SNS indicator was increased in the AB group only. Compared to LBNP −30, LBNP + ES increased SV (by 20%) and Q˙c (by 16%), and decreased TPR (by 12%) in the PARA group. MAP was unchanged from REST during all trials, for both groups. The orthostatic challenge induced by LBNP −30 elicited similar cardiovascular adaptations in PARA and AB subjects. ES-induced muscle contractions during LBNP −30 augmented the cardiovascular responses exhibited by the PARA group, probably via reactivation of the skeletal muscle pump and improved venous return.

Cardiovascular responses during arm exercise and orthostatic challenge in individuals with paraplegia.

Abstract. In this study the cardiorespiratory responses during arm crank ergometry (ACE) performed at two submaximal intensities (30% and 50% of heart rate reserve) and moderate orthostatic challenge were investigated in individuals with paraplegia (PARA). The effect of concurrent electrical stimulation (ES)-induced leg muscle contractions on the responses to ACE during orthostatic challenge was also investigated. Eight PARA (T5–T12) and eight able-bodied (AB) individuals participated in this study, however only seven subjects from each group completed all tests and were used in subsequent data analyses. Oxygen uptake (

Functional electrical stimulation-supported interval training following sensorimotor-complete spinal cord injury: a case series.

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S.P.20 Predictors of ankle instability in children and young people with Charcot–Marie–Tooth disease

), heart rate (fc), stroke volume (SV) and cardiac output (

The placebo effect of ankle taping in ankle instability.

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Cardiovascular responses during submaximal electrical stimulation-induced leg cycling in individuals with paraplegia

) were assessed during (1) ACE alone, (2) ACE and lower body negative pressure (ACE+LBNP), and, in PARA only, (3) ACE+LBNP with ES (ACE+LBNP+ES). In both PARA and AB, ACE+LBNP decreased SV (by 13–18% and 20–23%, respectively) and increased fc (by 13–15% and 16%, respectively) compared to ACE alone. The decrease in SV was greater in AB than in PARA (significant group × trial interaction; both ACE intensities pooled), but there was no difference in the magnitude of increase in fc between groups. ES-induced leg muscle contractions increased SV (up to 16%) but did not change

Oxygen uptake and heart rate responses during arm vs combined arm/ electrically stimulated leg exercise in people with paraplegia

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