No abstract

Objective: To establish normative values and a reference equation for the number of steps climbed during the six-minute step test (6MST) in healthy adults, and to assess the reliability of the test and of the equation. Methods: This was a multicenter cross-sectional study involving 468 healthy volunteers (age range: 18-79 years) recruited from the general community in six research laboratories across different regions of Brazil, which is a country with continental dimensions. The 6MST was performed twice (30-min interval), and clinical, demographic, and functional variables were evaluated. An independent sample of 24 volunteers was evaluated to test the reference equation a posteriori. Results: The number of steps had excellent test-retest reliability (intraclass correlation coefficient = 0.96 [95%CI: 0.95-0.97]), and the mean number of steps was 175 ± 45, the number being 14% greater in males than in females. The best performance on the test was correlated with age (r = -0.60), sex (r = 0.28), weight (r = 0.13), height (r = 0.41), BMI (r = -0.22), waist circumference (r = -0.22), thigh circumference (r = 0.15), FVC (r = 0.54), and physical activity level (r = 0.17; p < 0.05 for all). In the regression analysis, age, sex, height, and weight explained 42% of the variability of the 6MST. Normative values were established for the 6MST according to age and sex. There was no difference between the 6MST values from the independent sample and its predicted values (157 ± 29 steps vs. 161 ± 25 steps; p = 0.47; 97% of predicted values). Conclusions: The normative values and the reference equation for the 6MST in this study seem adequate to accurately predict the physical functional performance in adults in Brazil.

Objective A modified incremental step test (MIST) performed in the home may facilitate entirely home-based pulmonary rehabilitation programs. The aims of this study were to investigate the reliability and responsiveness, and the utility of the MIST for exercise prescription in people with stable chronic lung disease. Methods The MIST was undertaken at the centre and home in random order, before and after pulmonary rehabilitation, with two tests at each time point. Reliability was assessed using intraclass correlation coefficient. Responsiveness was evaluated as effect size. The minimal important difference was appraised using distribution and anchor-based methods. In a sub-study, physiological responses to MIST were measured by a portable metabolic system, followed by a constant step rate test at 60% of peak oxygen uptake (v̇O2peak), to evaluate utility for exercise prescription. Results Forty-six participants were recruited (29% of eligible candidates). There was excellent reliability for number of steps recorded in home and centre-based settings (intraclass correlation coefficient 0.954, 95%CI 0.915 to 0.976). A small-moderate effect size was demonstrated following pulmonary rehabilitation (0.34) and the minimal detectable change was 7 steps. All participants in the sub-study achieved 60% of v̇O2peak and achieved steady state by the 4th minute, with 60% of v̇O2 peak corresponding to mean 37% (95%CI 29 to 44) of the MIST final level. Conclusions The MIST is reliable and responsive to pulmonary rehabilitation in people with stable chronic respiratory disease. It provides new opportunities to assess exercise capacity, prescribe exercise training and reassess exercise program outcomes in environments where established field walking tests are not feasible. Impact Pulmonary rehabilitation is a highly effective treatment that is underutilised worldwide. Home-based pulmonary rehabilitation may improve access for patients and deliver equivalent clinical outcomes, but is limited by the availability of a robust exercise test that can be used at home to assess exercise capacity and prescribe training intensity. This study tested the clinimetric properties of the modified incremental step test and demonstrated a new way to assess exercise capacity, prescribe exercise training of an appropriate intensity and reassess exercise capacity in environments where established field walking tests are not feasible.

Objetivo deste estudo foi investigar a relação entre os estados de humor, a variabilidade da frequência cardíaca (VFC) e creatina quinase (CK) de para-atletas brasileiros. Foram avaliados 12 atletas, integrantes da Seleção Brasileira de Para-Atletismo. Para avaliar a resposta autonômica foi determinada a VFC em repouso, coletando os intervalos R-R em 10 min. Foram coletadas também amostras de sangue para analisar a CK total e para conhecer os estados de humor dos atletas, foi utilizado a Escala de Brums, sendo calculados os seis estados de humor (tensão, depressão, raiva, fadiga, confusão e vigor). A análise dos dados foi realizada pela correlação de Sperman. Os principais resultados demonstraram relação entre a modulação parassimpática e o Vigor dos atletas (r = 0,50 a 0,53; p<0,05). A CK não se relacionou com nenhum marcador. Conclui-se que houve relação entre a modulação parassimpática da VFC e o Vigor, o que é positivo para o rendimento na competição.

No abstract