Efeitos da estimulação elétrica neuromuscular de corpo inteiro nos indicadores de saúde de idosos

Abstract

Resistance training positively impacts muscle strength, muscle mass and functional capacity in the older people. However, due to physical limitations or simple aversion to regular exercise, most older people do not reach the recommended doses of exercise, an unsatisfactory adherence rate. In this sense, whole-body electromyostimulation (WBEMS) emerges, a new training technology with low impact on joints and potentially effective time to generate positive effects on health-related outcomes in the older people. This master's thesis aimed to contribute to a better understanding of the use of WB-EMS in the older people, investigating and developing, respectively: 1) The effects, safety and adverse events of WB-EMS on health-related outcomes in the older people , by conducting a systematic review; 2) A resistance training protocol with WB-EMS for the older people compared to conventional resistance training. To our knowledge, to date, no systematic review has proposed to investigate the effects of WB-EMS, specifically in the older people. Thus, the aim of the systematic review presented in the dissertation was to summarize the evidence on the effects of WB-EMS in the older people on health-related outcomes, as well as the risks and adverse events. Eligible studies were identified from searches in the MEDLINE, CENTRAL, EMBASE, CINAHL, Web of Science, Scopus and SPORTDiscuss databases. To assess the methodological quality of the studies, the RoB (risk of bias) tool from the Cochrane collaboration was used. To assess the level of certainty of evidence for each comparison, the GRADE (Grading of Recommendations Assessment Development and Evaluation) was used. Thirteen randomized controlled trials were included (pooled sample n = 283 participants). For the meta-analysis, the random effects model was used. Effect estimates were expressed as SMD (standardized mean difference) along with 95% confidence intervals. Heterogeneity between studies was assessed using the I2 test. Based on studies conducted in the medium term, the following were observed: large effects of WB-EMS for reducing the sarcopenia Z-score (ES: -1.44 [-2.02: -0.87], p= < 0.01), with low quality of evidence; moderate effects of WB-EMS to increase handgrip strength (ES: 0.58 [0.23: 0.92], p= < 0.01) and increase usual gait speed (ES: 0.69 [0.31: 1.07], p= < 0.01), both with low quality of evidence; no observed effect of WB-EMS on triglycerides (p= 0.20), with low quality of evidence; no observed effect of WB-EMS on total body fat (p= 0.20) and waist circumference (p= 0.17), both with very low quality of evidence. Based on long-term studies, the following were observed: large effects of WB-EMS for increasing isometric knee extension strength (ES: 0.81 [0.41: 1.21], p= < 0.01), with low quality of evidence; moderate effects of WB-EMS on increasing appendicular skeletal muscle mass (ES: 0.69 [0.30: 1.09], p= < 0.01), with low quality of evidence. Regarding risks, two studies evaluated muscle damage through blood levels of creatine kinase. Both reported that there was no significant difference between groups. Only one study reported a participant dropping out due to discomfort with the electrical current. No injuries or adverse events were observed. Although the WB-EMS has shown positive medium and long-term effects on healthrelated outcomes in the older people, the comparator groups mostly consisted of no intervention, protein supplementation, or low-intensity active exercise. This fact motivated us to develop a randomized clinical trial protocol, with the objective of comparing the effects of WB-EMS with an active control group, which will perform conventional resistance training. Thus, it will be possible to evaluate, through a fair comparison, if the resistance training with WB-EMS is equivalent, inferior or superior to the conventional resistance training and if the observed effects are maintained over 6 months. Additionally, patient-centered outcomes will be evaluated, which have not yet been evaluated in previous studies, such as social participation, falls-efficacy and satisfaction with the treatment. Overall, the studies included in this master's dissertation provide an important contribution regarding the WB-EMS in the older people. First, the systematic review of the effects, risks and adverse events of WB-EMS in the older people showed, based on 13 clinical trials, ranging from very low to low certainty of evidence, that this new therapeutic method was effective in increasing strength, muscle mass and functional capacity in the older people, both in the medium term (especially when associated with protein supplementation) and in the long term. Secondarily, the development of a WBEMS protocol for the older people, compared to an active control group, which will perform conventional resistance training, will elucidate whether there is equivalence, superiority or inferiority of this new training method on outcomes such as muscle strength, muscle mass, functional capacity, social participation and falls-efficacy, immediately after the intervention period and longitudinally, after 3 and 6 months.