Eficácia de intervenções para melhora da resistência muscular em idosos: revisão sistemática da literatura

Abstract

Aging is associated with a decline in most physiological systems in the body, including the musculoskeletal system. This is due to the muscular loss that is mainly due to a marked infiltration of fibrous and adipose tissue in the musculoskeletal system and loss of muscle fibers of all types, with the loss of type II fibers (related to muscle strength) Than type I (related to muscular endurance). Muscle performance characteristics, which include strength and endurance, are compromised by aging. As daily activities require more commonly muscular endurance and not just muscle strength per se, muscular endurance gain is as or even more important than absolute muscle strength gain. Therefore, the primary objective of this study was to conduct a systematic review of the literature to determine the efficacy of intervention programs in improving muscular endurance in the elderly. The secondary objective was to evaluate the efficacy of these programs in improving other functional and health outcomes in this population. A systematic review of the literature based on the Prisma Protocol (Present Reporting Items for Systematic Reviews and Meta-Analyzes) was carried out, searching the MEDLINE, PEDro, LILACS and SCIELO databases, using a specific search strategy involving descriptors related to the elderly and muscular endurance. We included studies published in Portuguese and English, of the quasi-experimental (QE) or randomized clinical trial (RCT), which involved elderly individuals and approached the skeletal muscles of lower limbs, upper limbs or trunk, and evaluated the efficacy of interventions for Improvement of muscular endurance. A total of 133 studies with the electronic search were found. Of these, only 13 met the inclusion criteria, being 7 RCTs and 6 QE. The mean score obtained by the RCTs on the PEDro scale was 5.57, while the mean score obtained by the TRENDs was 18.57. Among the seven RCTs, all were classified as having adequate methodological quality. Most of the studies (9, 69.23%) were performed in healthy elderly individuals, and most of them were sedentary. A variety of evaluation and intervention protocols were used, but most met the specific characteristics of the muscle endurance concept (submaximal overload, greater number of repetitions, contractions sustained over a prolonged period). Improvement in muscular endurance was observed in nine (69.23%) of the 13 included studies. Improvement in muscle endurance was accompanied by improvement of secondary endpoints such as muscle strength, muscle power, flexibility, cardiovascular endurance, balance, walking speed, fear of falling, and quality of life that are important for the functionality and health of the elderly. According to the results of most of the included studies, the programs of interventions developed, following the specific characteristics of the concept of muscular endurance, are effective in improving muscular endurance and other functional and health outcomes of healthy elderly. Further studies are needed to investigate the efficacy of targeted interventions to improve muscle endurance in elderly individuals who have some associated health condition or specific disability.