Many studies have investigated the relationship between hypertension and its association with muscle health, showing controversial results on the subject. It is believed that high blood pressure can ...reduce the blood supply and cause damage to the arteries that supply areas of the motor cortex, responsible for muscle contraction and mobility, leading to a decay of functionality and reduced oxygen consumption and muscle strength. However, during aging there is a natural decrease in muscle mass, strength and quality, associated with the process of sarcopenia, although there are still difficulties identifying which factors are responsible for causing and worsening this process. In this context, it is believed that hypertension may play an important role in understanding this issue.
compare isokinetic muscle function, muscle mass and gait speed among normotensive and hypertensive older adults.
A cross-sectional observational study was conducted with 81 community-dwelling older adults selected by convenience. Participants were older people capable of walking without assistance and without cognitive alterations detectable by the Mini-Mental State Examination (MMSE). The diagnosis of arterial hypertension (independent variable) was made through the self-report of the participant´s previous medical diagnosis of arterial hypertension, validated by the record of using antihypertensive medication. The dependent variables of the study were: peak torque, muscle power, work by body weight and agonist-antagonist ratio of hip, knee and ankle (isokinetic dynamometry), handgrip strength (handgrip dynamometry), muscle mass (calf circumference) and usual gait speed at 10 meters. The dependent variables were compared between the groups of normotensive and hypertensive older adults by means of simple analyses and covariance adjusted for sex.
most participants were female (51.9%), active (53.1%) and hypertensive (74%). In the simple analyses, it was observed that the hypertensive older group presented lower handgrip strength, lower mean peak torque of hip extensors and knee flexors, lower muscle power of knee flexors and extensors, lower work by body weight of hip flexors and knee extensors and lower knee agonist-antagonist ratio. However, in the analysis of covariance adjusted for sex, only in the knee agonist-antagonist ratio was found a statistically significant difference between the groups (40.64±9.01 vs 45.78±7.34; p=0.040).
The study identified a lower knee agonist-antagonist ratio in hypertensive older adults when compared to normotensive patients. Our findings are linked to changes in muscle functioning that reflect uncoordinated activation of knee agonists and antagonists, although such changes cannot be fully explained by a significant reduction in strength.
The understanding of hypertension and its impacts on muscle health contributes to a better understanding of the factors that cause and worsen the decline of muscle function in the older adults, in addition to being a potential contributor to the planning of health care strategies for the older people with a focus on the prevention and correct prescription of physical exercises.
Este estudo buscou analisar a associação entre testes de capacidade funcional, desempenho dos músculos do joelho e composição corporal de idosas com baixa densidade óssea. Foi desenvolvido um estudo ...transversal com 48 idosas (70,62±5,95 anos). Avaliou-se a capacidade funcional (testes Timed Up and Go - TUG e levantar e sentar na cadeira - TLS), desempenho muscular de joelho (dinamômetro isocinético), massa muscular (índice muscular esquelético com BIA) e massa magra (dobras cutâneas). A maioria da amostra era ativa ou moderadamente ativa (95,8%), apresentou sobrepeso (68,75%), ausência de sarcopenia (62,5%) e desempenho médio de 7,7 segundos no TUG e de 11,21 segundos no TLS. Observaram-se correlações negativas moderadas e baixas da capacidade funcional com as variáveis de desempenho muscular de joelho. A massa muscular apresentou correlação positiva baixa com potência de extensores de joelho e não apresentou correlação com a capacidade funcional, a qual apresentou associação somente com o desempenho muscular, reforçando a fragilidade do uso da massa muscular como medida única na identificação de sarcopenia.
