Multicomponent exercise training in cardiovascular complexity in prefrail older adults: a randomized blinded clinical pilot study

The aim of this study was to investigate the effects of multicomponent training on baroreflex sensitivity (BRS) and heart rate (HR) complexity of prefrail older adults. Twenty-one prefrail community-dwelling older adults were randomized and divided into multicomponent training intervention group (MulTI) and control group (CG). MulTI performed multicomponent exercise training over 16 weeks and CG was oriented to follow their own daily activities. The RR interval (RRi) and blood pressure (BP) series were recorded for 15 min in supine and 15 min in orthostatic positions, and calculation of BRS (phase, coherence, and gain) and HR complexity (sample entropy) were performed. A linear mixed model was applied for group, assessments, and their interaction effects in supine position. The same test was used to assess the active postural maneuver and it was applied separately to each group considering assessments (baseline and post-intervention) and positions (supine and orthostatic). The significance level established was 5%. Cardiovascular control was impaired in prefrail older adults in supine position. Significant interactions were not observed between groups or assessments in terms of cardiovascular parameters. A 16-week multicomponent exercise training did not improve HR complexity or BRS in supine rest or in active postural maneuver in prefrail older adults.

Baroreflex sensitivity in frailty syndrome

Frailty is related to a decrease in the physiological reserves, which causes difficulties in maintaining homeostasis. An example of physiological mechanisms for cardiovascular homeostasis is the baroreflex. The aim of this study was to compare baroreflex among frail, prefrail, and nonfrail individuals, in supine and orthostatic positions. Community-dwelling older adults were evaluated and categorized into frail, prefrail, or nonfrail groups, according to frailty phenotype. The RR interval (RRi) and systolic blood pressure (SBP) series were recorded for 15 min in the supine and 15 min in the orthostatic positions. Mean and variance of RRi and SBP, and baroreflex evaluated by phase, gain (α), and coherence (K2) were determined. A two-way repeated measures ANOVA, with Tukey's post hoc, was applied for group, position, and their interaction effects. The significance level established was 5%. Prefrail and frail participants did not present a significant decrease in mean values of RRi after postural challenge (893.43 to 834.20 ms and 925.99 to 857.98 ms, respectively). Frail participants showed a reduction in RRi variance in supine to orthostatic (852.04 to 232.37 ms2). Prefrail and frail participants showed a decrease in K2 after postural change (0.69 to 0.52 and 0.54 to 0.34, respectively). Frail participants exhibited lower values of K2 (0.34) compared to nonfrail and prefrail participants (0.61 and 0.52, respectively). Baroreflex indicated the presence of decoupling between heart period and SBP in frail and prefrail. Thus, reduced K2 might be a marker of the frailty process.

Efeito da rotação do quadril na sindrome da dor femoropatelar / Effect of hip rotation on patellofemoral pain syndrome

A proposta deste trabalho foi investigar o efeito da rotacao do quadril na atividade eletrica dos musculos Vasto Medial Obliquo (VMO). Vasto Lateral Obliquo (VLO) e Vasto Lateral Longo (VLL) no agachamento a 45o. de flexao do joelho associado a posicao neutra, rotacao laterala 45o. e rotacao medial a 15 e 30o. de quaril. Materiais e metodos: foram avaliadas 27 mulheres, sendo 15 mulheres normais do grupo controle (21,1+-2,1 anos) e 12 portadoras de sindrome da Dor Femoropatelar (SDFP) (21,0+-2,3 anos). A atividade eletrica do musculo quadriceps foi captada opr eletrodos ativos diferenciais simples de superficie, eletromiografo de 8 canais e programa Aqdados 7.2.6. Os dados foram normalizados pela porcentagem da media do agachamento a 75o. com o quadril em posicao neutra - RMS (uV). A analise estatistica utilizada foi ANOVA two way com medidas repetidas e Turkey pos hoc (p<-0,05). Resultados: os resultados evidenciaram interacao entre grupos e musculos (p=0,00), independente da posicao do quadril (p=0,39) e nao houve interacao entre grupos e posicoes do quadril (p=0,96). Os musculos VMO e VLL do grupo SDFP apresentaram atividade eletrica significativamente maior que o VMO (p=0,00) e VLL (p=0,04) do grupo controle. Por outro lado, a atividade eletrica do musculo VLO nao apresentou diferenca significativa entre os grupos (p=0,99). Conclusao: os resultados dessa pesquisa, nas condicoes experimentais utilizadas, sugerem que a rotacao do quadril nao influenciou a atividade eletrica das porcoes do quadriceps nos dois grupos no agachamento a 45o. de flexao do joelho