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This study investigated the initial three-month impact of the COVID-19 pandemic on the explicit processes towards physical activity (PA). In addition, we explored whether potential changes in explicit processes are associated with changes in PA and sedentary behavior (SB). Seventeen older adults (aged 65.7 ± 3.8 years; 76.5% women) with hypertension were included in this longitudinal study performed in Natal, Brazil. Explicit processes (explicit attitude [perceived benefits and cons perceived], social norms, social modeling, self-efficacy, intention and motivation) were evaluated through self-reported questionnaire before (January to March 2020) and during (June 2020) the COVID-19 pandemic. In addition, PA and SB were measured by accelerometry during seven days. Generalized linear and mixed models were used for data analysis. There was a decrease in the explicit attitudes (ß = - 4.8, p = 0.001) and moderate-vigorous PA (ß = - 4.8, p = 0.035) during the COVID-19. Changes in the explicit attitudes were associated with the changes in the moderate-vigorous PA (ß = - 1.6, 95% CI - 2.9, - 0.3, p = 0.034). No significant changes were found in the additional explicit process measures, time spent doing light PA and SB, and step count. Our findings may suggest that the COVID-19 pandemic has negatively impacted the explicit attitudes related to PA and contributed to decrease the time spent in the moderate-vigorous PA in older adults with hypertension.

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Objectives: Herein, we explored the associations of pre-pandemic COVID-19 physical activity (PA), sedentary behavior (SB) and cardiorespiratory fitness (CRF) with mental health and quality of life in older adults with hypertension.Method: Objectively measured PA and SB, perceived stress, depression symptoms, and quality of life were assessed before and during the pandemic in seventeen older adults with hypertension. CRF was assessed before the pandemic by cardiopulmonary exercise testing. Longitudinal and cross-sectional associations were analyzed using the mixed linear model.Results: Pre-pandemic light PA (positive association) and SB (negative association) were associated with quality of life during the pandemic. Higher pre-pandemic CRF was associated with less negative changes in perceived stress, depression symptoms, and quality of life during the pandemic.Conclusion: Our preliminary findings suggest that a healthier pre-pandemic movement behavior (more PA, less SB) and better CRF can mitigate the negative impact of the COVID-19 pandemic on mental health and quality of life in older adults with hypertension.

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BACKGROUND: This study reports the accelerometer-based physical activity (PA) and sedentary behavior (SB) before and during the COVID-19 pandemic in hypertensive older adults. METHODS: Thirty-five hypertensive older adults were included in this observational study. Accelerometer-based PA and SB measures were assessed before (January to March 2020) and during (June 2020) the COVID-19 pandemic. Linear mixed models were used to assess within-group changes in PA and SB measures, adjusted by accelerometer wear time. RESULTS: Before COVID-19 pandemic participants presented: 5809 steps/day (SE = 366), 303.1 min/day (SE = 11.9) of light PA, 15.5 min/day (SE = 2.2) of moderate-vigorous PA, and 653.0 min/day (SE = 12.6) of SB. During COVID-19 pandemic there was a decrease in steps/day (ß = -886 steps/day, SE = 361, p = 0.018), in moderate-vigorous PA (ß = -2.8 min/day, SE = 2.4, p = 0.018), and a trend in light PA (ß = -26.6 min/day, SE = 13.4, p = 0.053). In addition, SB increased during the COVID-19 pandemic (ß = 29.6 min/day, SE = 13.4, p = 0.032). The magnitude of changes was greater on the weekend, mainly for steps/day (ß = -1739 steps/day, SE = 424, p < 0.001) and the SB pattern (more time spent in bouts of ≥10 and 30 min, less breaks/day and breaks/h). CONCLUSIONS: The COVID-19 pandemic may elicit unhealthy changes in movement behavior in hypertensive older adults. Lower PA, higher and more prolonged SB on the weekend are the main features of the behavioral changes.

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The aim of this study was to investigate whether carbohydrate mouth rinse (CMR) improves physical performance of cyclists during a 30-km time trial test and its influence on water balance compared to other strategies of fluid intake. Eleven recreationally trained male cyclists completed a 30 km time trial cycle ergometer under three experimental interventions: (a) CMR, (b) drinking to replace all weight loss (DWL), and (c) drinking "ad libitum" (DAL). Time to complete the 30 km time trial, heart rate, average power, velocity, weight loss, urine color, urine density and pH were evaluated. Statistical analysis was performed using repeated measures analysis of variance (RM-ANOVA) and generalized estimating equations (GEE) with Bonferroni adjustment (p < 0.05). Time to complete the 30 km time trial was similar among CMR 54.5 ± 2.9 min, DWL 53.6 ± 3.9 min and DAL 54.5 ± 2.5 min (p = 0.13). CMR (1.7 ± 0.4%) elicited similar water loss compared to the DAL (1.4 ± 0.6%) intervention, but it was higher than the DWL intervention (0.6 ± 0.6%) (p < 0.01). CMR did not improve the performance of recreationally trained cyclists in a 30 km time trial test compared to other fluid intake strategies. Furthermore, CMR causes higher water loss compared to DWL intervention.

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Pleasure plays a key role in exercise behavior. However, the influence of cycling cadence needs to be elucidated. Here, we verified the effects of cycling cadence on affect, perceived exertion (ratings of perceived exertion), and physiological responses. In three sessions, 15 men performed a maximal cycling incremental test followed by two 30-min constant workload (50% of peak power) bouts at 60 and 100 r/min. The pleasure was higher when participants cycled at 60 r/min, whereas ratings of perceived exertion, heart rate, and oxygen uptake were lower ( p < .05). Additionally, the rate of decrease in pleasure and increase in ratings of perceived exertion was less steep at 60 r/min ( p < .01). Cycling at 60 r/min is more pleasant, and the perceived effort and physiological demand are lower than at 100 r/min.

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The rating of perceived exertion (RPE) is ability to detect and interpret organic sensations while performing exercises. This method has been used to measure the level of effort that is felt during weight-training at a given intensity. The purpose of this investigation was to compare session RPE values with those of traditional RPE measurements for different weight-training muscle actions, performed together or separately. Fourteen women with no former weight-training experience were recruited for the investigation. All participants completed five sessions of exercise: familiarization, maximum force, concentric-only (CONC-only), eccentric-only (ECC-only), and dynamic (DYN = CONC + ECC). The traditional RPE method was measured after each series of exercises, and the session RPE was measured 30 min after the end of the training session. The statistical analyses used were the paired t-test, one-way analysis of variance, and repeated measures analysis of variance. Significant differences between traditional RPE and session RPE for DYN, CONC, and ECC exercises were not found. This investigation demonstrated that session RPE is similar to traditional RPE in terms of weight-training involving concentric, eccentric, or dynamic muscle exercises, and that it can be used to prescribe and monitor weight-training sessions in older subjects.

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The purpose of this study was to verify the self-selected intensity during resistance training (RT) in older women. Twenty healthy women (mean age, 65.6 years) underwent a 2-week familiarization period followed by 3 experimental sessions. During the first session, anthropometric measurements were taken. The second session involved completion of a 1 repetition maximum (1RM) test for the following exercises: chest press, leg press, lat pull-down, leg extension, lateral shoulder raise, leg curl, biceps curl, and triceps pushdown. Last, a single RT session was performed at a self-selected intensity. During the RT session, participants were instructed to self-select a load for performing 3 sets of 10-15 repetitions. Data were analyzed by mean (SD) and analysis of variance with repeated measures (p < 0.05). Global mean of the 3 sets was bench press 41.0% 1RM (11.9), leg press 43.0% 1RM (17.2), lat pull-down 47.2% 1RM (11.1), leg extension 33.0% 1RM (8.1), lateral shoulder raise 51.1% 1RM (12.1), leg curl 43.5% 1RM (8.8), biceps curl 48.0% 1RM (15.5), and triceps pushdown 51.7% 1RM (13.3); there were no significant differences between the sets (p > 0.05). These results indicate that inactive older women self-selected an intensity exercise during RT below the recommendation for improvements on muscle fitness in apparently healthy older adults. However, this intensity is recommended for very deconditioned individuals. Nevertheless, the use of self-selection strategy during an exercise program can have greater advantages because of its easy applicability, its positive relation with exercise adherence, and for promoting initial muscle conditioning in older adults. Furthermore, it is crucial to gradually increase the RT load to guarantee better and sustainable effects on muscle fitness. Finally, future studies are needed to establish the chronic effects of RT at self-selected intensity on muscle fitness and the functional health of older adults.

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To develop and validate a modified OMNI rating of perceived exertion (RPE) scale for use during bench stepping exercise (OMNI-BS). Thirty women (age: 19.8 ± 1.8 years) undertook 2 experimental trials, separated by 7 days. Concurrent validity was established by examining the relation between physiological criterion variables, oxygen consumption (VO2), and heart rate (HR), with the concurrent variable, RPE from OMNI-BS, during 2 trials in which the intensity increased linearly (test 1) and intermittently (test 2). The first test consisted of 3-minute stages. Subjects stepped up and down on the bench at 120 b·min(-1). The test was terminated owing to subject fatigue. Exercise intensity increased as bench height increased every 3 minutes. The second test consisted of three 3-minute exercise bouts that reproduced exercise stage 1 (low intensity), stage 3 (moderate intensity), and stage 5 (high intensity) performed in the first test. The order of these 3 exercise bouts was counterbalanced. Intraclass correlation analysis from experimental trials indicated a strong positive association between RPE and VO2 (r = 0.96 and r = 0.95) and HR (r = 0.95 and r = 0.95). Concurrent validity for the OMNI-BS RPE scale was established for women performing bench stepping exercise.

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The aim of this study was to compare acute affective responses at exercise intensities based on the ventilatory threshold between normal weight, overweight, and obese women. 66 sedentary women (22 in each Body Mass Index group) performed a maximal graded treadmill test to measure their maximal oxygen uptake and ventilatory thresholds. Affective valence was compared at intensities spanning the ventilatory threshold (below, at, and above threshold). Affective valence below ventilatory threshold did not differ among the Body Mass Index groups. The obese group had a lower affective response at ventilatory threshold and above ventilatory threshold than the normal weight and overweight groups; the latter two groups did not differ. The obese group had a lower affective response than the normal and overweight groups, which corresponds to a less pleasant experience. Exercise prescriptions for obese subjects targeting intensities below ventilatory threshold can provide a more pleasant experience and may facilitate exercise adherence.

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The aim of this study was to investigate gender-based differences in substrate use during exercise at a self-selected pace. Seventeen men and 17 women performed a maximal exercise test and a 20-minute bout of self-paced treadmill walking to determine carbohydrate and fat oxidation rates. Gas exchange measurements were performed throughout the tests, and stoichiometric equations were used to calculate substrate oxidation rates. For each individual, a best-fit polynomial curve was constructed using fat oxidation rate (g·min(-1)) vs. exercise intensity (percentage of maximal oxygen uptake, % VO(2)max). Each individual curve was used to obtain the following variables: maximal fat oxidation (MFO), the peak rate of fat oxidation measured over the entire range of exercise intensities; fat(max), the exercise intensity at which the MFO was observed; and fat(max) zone, range of exercise intensities with fat oxidation rates within 10% of fat oxidation rates at fat(max). Although the MFO was similar between genders, fat(max) was lower in men than in women. Similarly, the "low" and "high" borders of the fat(max) zone were lower in men than in women. During exercise at a self-selected pace, carbohydrate oxidation rates were greater in men than in women, despite no gender-based differences in fat oxidation rates. However, fat oxidation contribution to total energy expenditure (EE) was greater in women than in men, despite no gender-based differences in the exercise intensity. In conclusion, although both genders self-selected a similar exercise intensity, the contribution of fat oxidation to EE is greater in women than in men. Interestingly, both genders self-selected an exercise intensity that falls within the fat(max) zone.

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