Short-term strength training improves muscle quality and functional capacity of elderly women

Abstract

To assess effects of a short-term strength training (ST) program on muscle quality (MQ) and functional capacity, 36 sedentary elderly women (age = 66.0 ± 8 year, height = 159.1 ± 9.2 cm, body mass = 68.3 ± 12.1 kg, body fat = 37.0 ± 4.2 %) were randomly divided into an experimental group (EG; n = 19) or a control group (CG; n = 17). The EG performed two to three sets of 12-15 repeats of leg press, knee extension, and knee flexion exercises, 2 days/week for 6 weeks. Before and after training, lower body one repetition maximum (1RM), functional performance tests, quadriceps femoris muscle thickness (MT), and muscle quality (MQ) (1RM and quadriceps MT quotient) were assessed. After training, only the EG showed significant improvements in 1RM (p < 0.05), 30-s sit-to-stand (p < 0.001), and 8 foot up-and-go (p < 0.001). In addition, only in the EG, significant increases in all quadriceps femoris MT measurements (vastus lateralis, vastus medialis, vastus intermedius, and rectus femoris) (p ≤ 0.05), and MQ (p < 0.001) were demonstrated. No changes were observed in the CG. Furthermore, there were significant associations between individual changes in MQ and corresponding changes in 30-s sit-to-stand (r = 0.62, p < 0.001), and 8 foot up-and-go (r = -0.71, p < 0.001). In conclusion, a ST program of only 6 weeks was sufficient to enhance MQ of the knee extensors in elderly women, which resulted in beneficial changes in functional capacity.

Effects of single vs. multiple-set short-term strength training in elderly women

“…The mechanisms responsible for training induced improvements in MQ are still unclear; however, neural adaptations (changes in motor unit recruitment, firing frequency, and summation of motor unit action potential synchronization) as well as enhancement of contractile properties may offer substantial support for the observed increases (Ivey et al 2000;Tracy et al 1999). The current results reinforce our previous findings that short-term ST is an effective method to improve MQ of elderly women (Pinto et al 2014). Furthermore, they suggest that during the early phase of ST, additional sets do not promote greater responses in variables associated with improvement of MQ.…”

“…Thus, the MQ was determined according to previous studies (Pinto et al 2014;Radaelli et al 2013) by the following equation: (MQ= knee extension 1-RM (kg) of the dominant leg/MT QUA SUM (mm) of the dominant leg).…”

“…Furthermore, the MQ seems to have a strong association with functional capacity in elderly people (Pinto et al 2014). A previous study reported that elderly women with lower MQ of lower body were 4.3 to 17.1 times more likely to have functional impairments (Barbat-Artigas et al 2013).…”

“…A study recently completed in our laboratory showed that short-term ST (6 weeks), with two to three sets per exercise, was effective in increasing strength, muscle mass, and improved MQ of the knee extensor muscles in elderly women (Pinto et al 2014). Although our results showed positive effects with multiple sets, some previous studies have suggested that single and multiple sets promote similar gains in strength and muscle hypertrophy (Fleck and Kraemer 2004;Wolfe et al 2004).…”

Influência dos treinamentos funcional e tradicional na potência muscular, qualidade de movimento e qualidade de vida em idosas: um ensaio clínico randomizado e controlado

“…Consequently, aspects such as decreased strength (dynapenia), muscle mass (sarcopenia), muscular power and joint mobility, directly reflect in the incidence of falls and the performance of activities of the daily living (ADL) in this population [2][3][4] . The main functional movements performed in everyday activities are a combination of strength, balance, resistance, power among other capabilities that at satisfactory levels allow safety and efficiency 5,6 .…”