RESUMO
BACKGROUND: Among the types of physical exercise, resistance exercises have been gaining significant attention in the COPD population. The aim of this study was to compare effects of conventional resistance training and of training by using elastic tubes on muscle strength, exercise capacity, and creatine kinase clearance in subjects with COPD. METHODS: Twenty-eight subjects with COPD were randomized into the following: resistance training with the elastic tubing group and resistance training with the weight-machine training group (conventional resistance group), performed 3 times a week for 12 weeks. The subjects were submitted to spirometry, functional exercise capacity (the 6-min walk test), muscle strength (dynamometry), and the repetition maximum test. Differences between the initial and final evaluations (Δ) and the (final - initial evaluations)/initial evaluations ×100 (Δ%) of each group were expressed as mean [95% CI]. RESULTS: Nineteen subjects (FEV1 % predicted, 52 ± 18; years, 65 ± 8) completed the training program. Similar improvements were observed in both modalities on muscle strength (knee extension, Δ%18 [6 to 29]; knee flexion, Δ%35 [17 to 54]; elbow flexion, Δ%28 [9 to 48]; shoulder abduction, Δ%41 [25 to 58] and shoulder flexion, Δ%31 [11 to 51] in the weight-machine training group (conventional resistance group); knee extension, Δ%15 [8 to 21]; knee flexion, Δ%28 [15 to 41]; elbow flexion, Δ%36 [22 to 51]; and shoulder abduction, Δ%43 [32 to 55] and shoulder flexion, Δ%43 [25 to 61] in the elastic tubing group, P < .05 for intra-group analysis and P > .05 for between groups analysis), 6-min walk test (baseline 493 ± 67m vs 12 weeks 526 ± 78 in the weight-machine training group (P = .10); baseline 493 ± 71 vs 12 weeks 524 ± 68 in the elastic tubing group (P < .01), P = .88 between groups). The elastic tubing group had lower accumulated creatine kinase levels between 24 and 72 h ((Δ%-24 [-31 to 16] than subjects in the weight-machine training group Δ%3 [-21 to 28], P = .042 between the groups. CONCLUSIONS: Training with elastic resistance provided similar changes in muscle strength and exercise capacity to conventional resistance group in the subjects with COPD. The elastic tubing group had faster creatine kinase clearance after a training session than the weight-machine training group (conventional resistance group). The ease of its application associated with similar training benefits to conventional training supported its application in clinical routine.
Assuntos
Terapia por Exercício/métodos , Tolerância ao Exercício , Força Muscular , Doença Pulmonar Obstrutiva Crônica , Treinamento Resistido/métodos , Creatina Quinase/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/terapia , Testes de Função Respiratória , Resultado do TratamentoRESUMO
BACKGROUND: Lemgruber® elastic tubing has been used as an adjunct to exercise training with positive effects in healthy adults and in patients with chronic lung disease. Despite its benefits, there is a lack of information on the specific resistance, elongation, reproducibility and safety of the different types of Lemgruber® elastic tubing. OBJECTIVES: The primary outcome was to assess the length-resistance relation (E/R) of five Lemgruber® elastic tubing of different diameters. Secondary outcomes included the development of reference equations of resistance according to elongation of Lemgruber® elastic tubing types and; the description of Lemgruber® elastic tubing safety and; the description of elongation of Lemgruber® elastic tubing using a clinically useful outcome (i.e. range of motion, in degrees). METHODS: The relation between elongation and resistance of Lemgruber® elastic tubing was investigated in a laboratory environment. Secondly, reference equations for the resistance according to the elongation in each Lemgruber® elastic tubing were calculated. Finally, the elongation of the tubing during movements in different degrees of range of motion were estimated using mathematical models, so that the resistance provided by the tubing for any exercise could be predicted. RESULTS: Lemgruber® elastic tubing provided a large array of resistance varying from 3±0.1Newtons (N) to 537±13N (mean±standard deviation). The maximal resistance deemed safe for each of the five Lemgruber® elastic tubing were: 173±25N, 280±23N, 409±40N, 395±37N and 537±13N. Reference equations had nearly perfect predictive power (r2=0.99) for all polynomial non-linear models (p<0.001 for all). CONCLUSIONS: Lemgruber elastic tubing progressively increased resistance with increased elongation. The large array of resistances delivered by Lemgruber® elastic tubing, along with its safety and good estimation of reference values, support its use in clinical practice.
Assuntos
Terapia por Exercício/instrumentação , Exercício Físico/fisiologia , Fenômenos Biomecânicos , Humanos , Reprodutibilidade dos Testes , Estresse MecânicoRESUMO
CONTEXTUALIZAÇÃO: As faixas elásticas são frequentemente utilizadas em programas de treinamento resistivo, entretanto a seleção da progressão entre os níveis de resistência elástica é feita de maneira subjetiva em virtude da deficiência de dados quantitativos que expressem o valor da resistência em função da tração do material. OBJETIVOS: Investigar a resistência elástica gerada em cada um dos oito níveis de resistências das faixas elásticas em 100 por cento de alongamento e quantificar a variação existente de um nível para outro. MÉTODOS: A amostra foi constituída de 80 corpos de prova, retirados dos oito níveis de resistência. O ensaio de tração nos corpos de prova modelo C foi realizado conforme a norma técnica ASTM D 412-06ª pela máquina universal de ensaios DL EMIC 3000. Cada ciclo de tração foi realizado na velocidade de 500 mm/seg. Para a análise estatística, utilizou-se o teste Anova one-way com nível de significância de ρ<0,05. RESULTADOS: A amostra apresentou diferença significativa da resistência elástica no espectro de níveis avaliados, exceto entre as resistências suaves (amarelo) e médias (vermelho). A análise da variação da resistência entre as faixas mostra que a dourada (máximo) oferece 5,13 vezes mais resistência que a branca (extrasuave), e a maior variação na progressão encontra-se entre as faixas preta e cinza. Além disso, o módulo de Young apresentou comportamento linear entre as diferentes cores. CONCLUSÕES: Os resultados mostraram que a variação da resistência elástica e da rigidez do material são progressivas entre os diferentes níveis. Além disso, os dados sugerem a possibilidade de progressão da faixa branca para a vermelha, eliminando a amarela na prescrição de exercícios de fortalecimento.
BACKGROUND: Elastic bands are frequently used for resistance training, however the selection of the bands to progress through the levels of elastic resistance is done in a subjective manner. This is due to the lack of quantitative data on the value of the material's resistance as a function of its tension. Objectives: To investigate the elastic resistance generated by each of the eight color-coded resistance levels of elastic bands, using 100 percent elongation, and to quantify the resistance variation from one level to the next. METHODS: Tensile testing was performed in compliance with ASTM Standard D412-06a. The sample consisted of 80 die-cut test specimens (Die C) taken from the eight color-coded resistance levels. The sample was submitted to tensile testing in the universal testing machine EMIC DL-3000. Each of the tension cycles was performed at a speed of 500mm/sec. Statistical analysis was done using one-way ANOVA, with a significance level of p<0.05. RESULTS: The sample showed a significant difference between all levels of resistance, except for the yellow (thin) and red (medium) elastic bands. The variation in resistance between the bands shows that the gold (max) band offers 5.13 times more resistance than the tan (extra thin) band, and that the greatest variation in progressive resistance is between the black and the silver bands. In addition, Young's modulus showed linear behavior between the different colors. CONCLUSIONS: The results showed that the elastic resistance and stiffness of the material exhibits a linear and progressive variation. In addition, the data suggested the possibility of progressing from the tan band to the red band, skipping the yellow band, when prescribing resistance exercises.