Changes in Physical Functioning and Fall-Related Factors in Older Adults Due to COVID-19 Social Isolation.

Background: Social isolation has been one of the main measures for the prevention of COVID-19. It's possible that, in addition to the natural aging-related deficits, social isolation has accelerated the decline of the different components of physical and mental capacity in older adults. This study aimed to compare the functional capacity and concern about falling in older adults before and during COVID-19 social isolation. Method: This observational longitudinal study was carried out with 45 community dwelling older adults (mean age 65.6 ± 4.6 years, 88.8% women). Functional capacity and concerns about falling assessments were carried out before the COVID-19 pandemic, and between the 16th and 18th week of social isolation. All testes were face-to-face, except the second FES-I assessment, which took place via telephone call in order to minimize a prolonged person-to-person contact. Muscle strength, muscle power, functional mobility, functional muscle fitness, upper and lower body flexibility, dynamic balance, and Efficacy Scale were assessments. Results: Regarding functional capacity, there was 14% decline in muscle strength (p<.001), 7% in power (p=.001), 11% in functional mobility (p=.001), 20% in functional muscle fitness (p=.001), and 60% in upper body flexibility (p=.001) and 33% lower body flexibility (p=.003). The dynamic balance and the concern about falling showed no statistically significant differences. Conclusion: Thus, it can be concluded that there was a decline in older adults' functional capacity during COVID-19 social isolation.

Acute Effects of Parallel Back Squat Performed in Different Set Configurations on Neuromuscular Performance.

We compared the acute effects of parallel back squat performed from different resistance training configurations on neuromuscular performance. Twenty-eight young adults underwent 4 experimental conditions: inter-repetition rest, traditional, traditional to failure, and rest-pause in the parallel back squat in a randomized, counterbalanced, and cross-over design. The neuromuscular performance was assessed through peak torque of knee extensors and flexors at two angular velocities (90 and 120 º/s) in three moments (before, post, and post-30 min). The peak torque of the knee extensors and flexors at 90 and 120 º/s decreased immediately after training for traditional, traditional to failure, and rest-pause (-8.1% to -17.7%, P<0.001). A greater reduction in the extensor peak torque was found at 120 º/s (P<0.05) in the rest-pause (-17.7%) when compared to traditional (-10.8%). The peak torque returned to baseline values only at post-30 min for the traditional configuration for the knee flexion action at 120 º/s. The peak torque remained similar for the muscular actions and angular velocities for the inter-repetition rest (P>0.05). Our results suggest the inter-repetition rest configuration seems to be a more appropriate strategy for maintaining the lower limb neuromuscular performance after a resistance training session.

Parasympathetic Nervous Activity Responses to Different Resistance Training Systems.

The assessment of parasympathetic nervous activity and psychophysiological responses infers the stress imposed by different resistance training systems. Therefore, we compare the effects of different sets configurations, with similar volume (~60 repetitions), on heart rate variability indices and internal training load. Twenty-nine resistance-trained adults completed the following conditions: traditional without and with muscle failure, inter-repetition rest, and rest-pause in the parallel squat. The heart rate variability indices (time-domain) were measured before and 30 min after each condition. The internal training load was obtained through the session-rating of perceived exertion method. Except for inter-repetition rest, all conditions reduced the heart rate variability indices after the session (P<0.05), and the rest-pause triggered the higher reductions (≤-46.7%). The internal training load was higher in the rest-pause (≤68.9%). Our results suggest that rest-pause configuration leads to more considerable disruption of the parasympathetic nervous activity and higher internal training load in trained adults. In contrast, inter-repetition rest allows lower autonomic and psychophysiological stress.