Exercício aeróbico ou com pesos melhora o desempenho nas atividades da vida diária de mulheres idosas

Este estudo aleatorizado não controlado teve como objetivo determinar o efeito de um protocolo de exercício com pesos ou aeróbico no desempenho das atividades da vida diária em mulheres idosas. Para tanto, a amostra foi constituída por 41 mulheres idosas aparentemente saudáveis na faixa etária de 60 a 85 anos de idade (x: 65,1 ± 7,9 anos) divididas aleatoriamente em grupo exercício com pesos (n: 22) ou aeróbico (n: 19). O grupo exercício com pesos consistiu na execução de três séries de oito a 12 repetições a 60% de uma repetição máxima no exercício leg press 45º. O grupo exercício aeróbico consistiu em pedalar em cicloergômetro durante 40 minutos a 60% da frequência cardíaca de reserva. Os dois protocolos foram realizados três vezes por semana durante cinco semanas. As atividades da vida diária selecionadas foram velocidade para se levantar de uma posição sentada (VLPS), velocidade para se levantar de uma posição deitada (VLPD), velocidade para subir escada (VSE) e velocidade para calçar e amarrar o tênis (VCAT). O grupo exercício aeróbico melhorou significativamente o desempenho em VCAT (19,1%), enquanto o exercício com pesos incrementou significativamente o desempenho em VSE (4,3%) e VLPS (8,9%). Os resultados deste estudo permitem concluir que tanto o exercício com pesos como o aeróbico induziram efeito positivo nas atividades da vida diária, sugerindo que ambas as modalidades de exercício devem ser associadas a um programa adequado de exercícios para a melhora da capacidade funcional de pessoas idosas.

Isokinetic analysis of ankle and ground reaction forces in runners and triathletes

OBJECTIVE: To analyze and compare the vertical component of ground reaction forces and isokinetic muscle parameters for plantar flexion and dorsiflexion of the ankle between long-distance runners, triathletes, and nonathletes. METHODS: Seventy-five males with a mean age of 30.26 (±6.5) years were divided into three groups: a triathlete group (n=26), a long-distance runner group (n = 23), and a non-athlete control group. The kinetic parameters were measured during running using a force platform, and the isokinetic parameters were measured using an isokinetic dynamometer. RESULTS: The non-athlete control group and the triathlete group exhibited smaller vertical forces, a greater ground contact time, and a greater application of force during maximum vertical acceleration than the long-distance runner group. The total work (180º/s) was greater in eccentric dorsiflexion and concentric plantar flexion for the non-athlete control group and the triathlete group than the long-distance runner group. The peak torque (60º/s) was greater in eccentric plantar flexion and concentric dorsiflexion for the control group than the athlete groups. CONCLUSIONS: The athlete groups exhibited less muscle strength and resistance than the control group, and the triathletes exhibited less impact and better endurance performance than the runners.

Equilíbrio, controle postural e força muscular em idosas osteoporóticas com e sem quedas

Um dos maiores problemas de saúde pública na população idosa são as quedas, agravando-se quando relacionadas à presença de osteoporose. Dentre os vários fatores de risco, destacam-se a diminuição do equilíbrio, controle postural e força muscular. O objetivo deste trabalho foi comparar o equilíbrio, o controle postural e a força muscular em idosas osteoporóticas com e sem quedas referidas no último ano. Foram avaliadas 45 mulheres entre 65 e 85 anos, divididas em dois grupos com base no relato de quedas nos 12 meses anteriores à avaliação: grupo com quedas (GCQ; n=21) e grupo sem quedas (GSQ; n=24). O equilíbrio foi avaliado por meio da escala de equilíbrio de Berg; o controle postural pelo teste clínico modificado de interação sensorial no equilíbrio (mCTSIB), realizado no equipamento Balance Master®; e a força muscular dos flexores e extensores de joelho e dorsiflexores de tornozelo, com dinamômetro EMG System do Brasil®. Foi considerado nível de significância α=0,05. Houve diferença significativa no equilíbrio (p<0,01) e na velocidade de oscilação do Centro de Pressão (CP) durante o teste mCTSIB nas condições olhos fechados superfície estável (p=0,05) e olhos abertos superfície instável (p<0,01), com valores maiores para o GCQ. Os grupos foram semelhantes entre si em relação à força muscular (p>0,05). Nossos resultados indicam que idosas osteoporóticas com histórico de quedas nos últimos 12 meses possuem pior equilíbrio e controle postural em relação às osteoporóticas sem quedas referidas.

Verbal and visual stimulation effects on rectus femoris and biceps femoris muscles during isometric and concentric

Abstract Background: Coactivation may be both desirable (injury prevention) or undesirable (strength measurement). In this context, different styles of muscle strength stimulus have being investigated. In this study we evaluated the effects of verbal and visual stimulation on rectus femoris and biceps femoris muscles contraction during isometric and concentric. Methods: We investigated 13 men (age =23.1 ± 3.8 years old; body mass =75.6 ± 9.1 kg; height =1.8 ± 0.07 m). We used the isokinetic dynamometer BIODEX device and an electromyographic (EMG) system. We evaluated the maximum isometric and isokinetic knee extension and flexion at 60°/s. The following conditions were evaluated: without visual nor verbal command (control); verbal command; visual command and; verbal and visual command. In relation to the concentric contraction, the volunteers performed five reciprocal and continuous contractions at 60°/s. With respect to isometric contractions it was made three contractions of five seconds for flexion and extension in a period of one minute. Results: We found that the peak torque during isometric flexion was higher in the subjects in the VVC condition (p > 0.05). In relation to muscle coactivation, the subjects presented higher values at the control condition (p > 0.05). Conclusion We suggest that this type of stimulus is effective for the lower limbs.

Effects of eccentric cycle ergometry in alpine skiers

Eccentric cycling, where the goal is to resist the pedals, which are driven by a motor, increases muscle strength and size in untrained subjects. We hypothesized that it could also be beneficial for athletes, particularly in alpine skiing, which involves predominantly eccentric contractions at longer muscle lengths. We investigated the effects of replacing part of regular weight training with eccentric cycling in junior male alpine skiers using a matched-pair design. Control subjects ( N=7) executed 1-h weight sessions 3 times per week, which included 4-5 sets of 4 leg exercises. The eccentric group ( N=8) performed only 3 sets, followed by continuous sessions on the eccentric ergometer for the remaining 20 min. After 6 weeks, lean thigh mass increased significantly only in the eccentric group. There was a groupxtime effect on squat-jump height favouring the eccentric group, which also experienced a 6.5% improvement in countermovement-jump height. The ability to finely modulate muscle force during variable eccentric cycling improved 50% (p=0.004) only in the eccentric group. Although eccentric cycling did not significantly enhance isometric leg strength, we believe it is beneficial for alpine skiers because it provides an efficient means for hypertrophy while closely mimicking the type of muscle actions encountered while skiing.

A smooth transition protocol for patients with multifocal motor neuropathy going from intravenous to subcutaneous immunoglobulin therapy: an open-label proof-of-concept study

Intravenous immunoglobulin (IVIG) is the first-line therapy for multifocal motor neuropathy (MMN). This open-label multi-centre study (NCT00701662) assessed the efficacy, safety, and convenience of subcutaneous immunoglobulin (SCIG) in patients with MMN over 6 months, as an alternative to IVIG. Eight MMN patients (42-66 years), on stable IVIG dosing, received weekly SCIG at doses equivalent to previous IVIG using a "smooth transition protocol". Primary efficacy endpoint was the change from baseline to week 24 in muscle strength. Disability, motor function, and health-related quality of life (HRQL) endpoints were also assessed. One patient deteriorated despite dose increase and was withdrawn. Muscle strength, disability, motor function, and health status were unchanged in all seven study completers who rated home treatment as extremely good. Four experienced 18 adverse events, of which only two were moderate. This study suggests that MMN patients with stable clinical course on regular IVIG can be switched to SCIG at the same monthly dose without deterioration and with a sustained overall improvement in HRQL.

[How to assess the nutritional status of my patient]

Protein-energy-malnutrition is a growing problem in industrialised countries. Many studies have found malnourishment in 20-60% of hospitalized medical or surgical patients, as well as out-patients. Malnutrition negatively influences patients' prognosis, immune system, muscle strength, and quality of life. As it is a largely treatable co-morbidity, systematic screening for malnutrition and effective management will improve patient outcomes and reduce healthcare costs. Early diagnosis and assessment depends on a simple and standardised screening tool that identifies at-risk patients, allowing the medical team in charge to solve patients' nutritional problems with an interdisciplinary approach.

Hindfoot varus and neurologic disorders

Muscle imbalance from numerous underlying neurologic disorders can cause dynamic and static hindfoot varus deformity. Most etiologies are congenital, and therefore affect bone morphology and the shape of the foot during growth. Weak and strong muscle groups, bone deformity, and soft-tissue contractures have to be carefully assessed and considered for successful management. Because of the variety of the etiologies and the differences in presentation, treatment decisions in varus hindfoot caused by neurologic disorders must be individualized. Deformity correction includes release of soft tissue contractures, osteotomies and arthrodeses, and tenotomies or tendon transfers to balance muscle strength and prevent recurrence. To decrease elevated anteromedial ankle joint contact stress and provide lateral hindfoot stability during the entire gait cycle, the goal of static and dynamic hindfoot varus realignment is to fully correct all components of the deformity, but particularly the varus tilt of the talus.

Nerve excitability changes in critical illness polyneuropathy

Patients in intensive care units frequently suffer muscle weakness and atrophy due to critical illness polyneuropathy (CIP), an axonal neuropathy associated with systemic inflammatory response syndrome and multiple organ failure. CIP is a frequent and serious complication of intensive care that delays weaning from mechanical ventilation and increases mortality. The pathogenesis of CIP is not well understood and no specific therapy is available. The aim of this project was to use nerve excitability testing to investigate the changes in axonal membrane properties occurring in CIP. Ten patients (aged 37-76 years; 7 males, 3 females) were studied with electrophysiologically proven CIP. The median nerve was stimulated at the wrist and compound action potentials were recorded from abductor pollicis brevis muscle. Strength-duration time constant, threshold electrotonus, current-threshold relationship and recovery cycle (refractoriness, superexcitability and late subexcitability) were recorded using a recently described protocol. In eight patients a follow-up investigation was performed. All patients underwent clinical examination and laboratory investigations. Compared with age-matched normal controls (20 subjects; aged 38-79 years; 7 males, 13 females), CIP patients exhibited reduced superexcitability at 7 ms, from -22.3 +/- 1.6% to -7.6 +/- 3.1% (mean +/- SE, P approximately 0.0001) and increased accommodation to depolarizing (P < 0.01) and hyperpolarizing currents (P < 0.01), indicating membrane depolarization. Superexcitability was reduced both in patients with renal failure and without renal failure. In the former, superexcitability correlated with serum potassium (R = 0.88), and late subexcitability was also reduced (as also occurs owing to hyperkalaemia in patients with chronic renal failure). In patients without renal failure, late subexcitability was normal, and the signs of membrane depolarization correlated with raised serum bicarbonate and base excess, indicating compensated respiratory acidosis. It is inferred that motor axons in these CIP patients are depolarized, in part because of raised extracellular potassium, and in part because of hypoperfusion. The chronic membrane depolarization may contribute to the development of neuropathy.

Combined endurance/resistance training early on, after a first myocardial infarction, does not induce negative left ventricular remodelling

BACKGROUND: Resistance training (RT) is safe and practicable in low-risk populations with coronary artery disease. In patients with left ventricular (LV) dysfunction after an acute ischaemic event, few data exist about the impact of RT on LV remodelling. METHODS: In this prospective, randomized, controlled study, 38 patients, after a first myocardial infarction and a maximum ejection fraction (EF) of 45%, were assigned either to combined endurance training (ET)/RT (n=17; 15 men; 54.7+/-9.4 years and EF: 40.3+/-4.5%) or to ET alone (n=21; 17 men; 57.0+/-9.6 years and EF: 41.9+/-4.9%) for 12 weeks. ET was effectuated at an intensity of 70-85% of peak heart rate; RT, between 40 and 60% of the one-repetition maximum. LV remodelling was assessed by MRI. RESULTS: No statistically significant differences between the groups in the changes of end-diastolic volume (P=0.914), LV mass (P=0.885) and EF (P=0.763) were observed. Over 1 year, the end-diastolic volume increased from 206+/-41 to 210+/-48 ml (P=0.379) vs. 183+/-44 to 186+/-52 ml (P=0.586); LV mass from 149+/-28 to 155+/-31 g (P=0.408) vs. 144+/-36 to 149+/-42 g (P=0.227) and EF from 49.1+/-12.3 to 49.3+/-12.0% (P=0.959) vs. 51.5+/-13.1 to 54.1% (P=0.463), in the ET/RT and ET groups, respectively. Peak VO2 and muscle strength increased significantly in both groups, but no difference between the groups was noticed. CONCLUSION: RT with an intensity of up to 60% of the one-repetition maximum, after an acute myocardial infarction, does not lead to a more pronounced LV dilatation than ET alone. A combined ET/RT, or ET alone, for 3 months can both increase the peak VO2 and muscle strength significantly.

Eccentric endurance training in subjects with coronary artery disease: a novel exercise paradigm in cardiac rehabilitation?

This study evaluated the effects of 8 weeks of eccentric endurance training (EET) in male subjects (age range 42-66 years) with coronary artery disease (CAD). EET was compared to concentric endurance training (CET) carried out at the same metabolic exercise intensity, three times per week for half an hour. CET ( n=6) was done on a conventional cycle ergometer and EET ( n=6) on a custom-built motor-driven ergometer. During the first 5 weeks of the training program the metabolic load was progressively increased to 60% of peak oxygen uptake in both groups. At this metabolic load, mechanical work rate achieved was 97 (8) W [mean (SE)] for CET and 338 (34) W for EET, respectively. Leg muscle mass was determined by dual-energy X-ray absorptiometry, quadriceps strength with an isokinetic dynamometer and muscle fibre composition of the vastus lateralis muscle with morphometry. The leg muscle mass increased significantly in both groups by some 3%. Strength parameters of knee extensors improved in EET only. Significant changes of +11 (4.9)%, +15 (3.2)% and +9 (2.5)% were reached for peak isometric torque and peak concentric torques at 60 degrees s(-1) and 120 degrees s(-1), respectively. Fibre size increased significantly by 19% in CET only. In conclusion, the present investigation showed that EET is feasible in middle-aged CAD patients and has functional advantages over CET by increasing muscle strength. Muscle mass increased similarly in both groups whereas muscle structural composition was differently affected by the respective training protocols. Potential limitations of this study are the cautiously chosen conditioning protocol and the restricted number of subjects.

Relationships between structural and functional measures of nutritional status in a normally nourished population

Both anthropometric and functional measurements have been used in nutritional assessment and monitoring. Hand dynamometry is a predictor of surgical outcome and peak expiratory flow rate has been used as an index of respiratory muscle function. This study aims to measure in normal subjects the relationship between anthropometric measurements, voluntary muscle strength by hand grip dynamometry and respiratory muscle function by peak expiratory flow rate.

Robot-aided neurorehabilitation of the upper extremities

Task-oriented repetitive movements can improve muscle strength and movement co-ordination in patients with impairments due to neurological lesions. The application of robotics and automation technology can serve to assist, enhance, evaluate and document the rehabilitation of movements. The paper provides an overview of existing devices that can support movement therapy of the upper extremities in subjects with neurological pathologies. The devices are critically compared with respect to technical function, clinical applicability, and, if they exist, clinical outcomes.

Energy beverages: content and safety.

Exercise is making a resurgence in many countries, given its benefits for fitness as well as prevention of obesity. This trend has spawned many supplements that purport to aid performance, muscle growth, and recovery. Initially, sports drinks were developed to provide electrolyte and carbohydrate replacement. Subsequently, energy beverages (EBs) containing stimulants and additives have appeared in most gyms and grocery stores and are being used increasingly by "weekend warriors" and those seeking an edge in an endurance event. Long-term exposure to the various components of EBs may result in significant alterations in the cardiovascular system, and the safety of EBs has not been fully established. For this review, we searched the MEDLINE and EMBASE databases from 1976 through May 2010, using the following keywords: energy beverage, energy drink, power drink, exercise, caffeine, red bull, bitter orange, glucose, ginseng, guarana, and taurine. Evidence regarding the effects of EBs is summarized, and practical recommendations are made to help in answering the patient who asks, "Is it safe for me to drink an energy beverage when I exercise?"

The effects of resistance training on well-being and memory in eldery volunteers

Objective: to determine the short- and long-term effects of resistance training on muscle strength, psychological well-being, control-beliefs, cognitive speed and memory in normally active elderly people. Methods: 46 elderly people (mean age 73.2 years; 18 women and 28 men), were randomly assigned to training and control groups (n = 23 each). Pre- and post-tests were administered 1 week before and 1 week after the 8-week training intervention. The training sessions, performed once a week, consisted of a 10 min warm-up phase and eight resistance exercises on machines. Results: there was a significant increase in maximum dynamic strength in the training group. This training effect was associated with a significant decrease in self-attentiveness, which is known to enhance psychological well-being. No significant changes could be observed in control-beliefs. Modest effects on cognitive functioning occurred with the training procedure: although there were no changes in cognitive speed, significant pre/post-changes could be shown in free recall and recognition in the experimental group. A post-test comparison between the experimental group and control group showed a weak effect for recognition but no significant differences in free recall. Significant long-term effects were found in the training group for muscular strength and memory performance (free recall) 1 year later. Conclusion: an 8-week programme of resistance training lessens anxiety and self-attentiveness and improves muscle strength.