This study aimed to explore the impact of caffeine (CAF) encapsulated in transferrin-modified, sterically-stabilized liposomes (Tf-SSL) on the physical performance of rats, specifically forelimb grip strength, running, and swimming. The brain-targeted drug delivery system, Tf-SSL, was used for the administration of caffeine. 168 male Sprague-Dawley (SD) rats were randomly assigned to different groups, including swimming, running, running wheel, and strength groups. Each group was further subdivided into high, medium, and low dose free caffeine (HCAF, MCAF, LCAF) and Tf-SSL CAF groups, along with a control group (CON). The strength, swimming, and running groups underwent training for four weeks, three times per week. The running wheel group was placed in rearing cages for a one-week adaptation period. After the final training session, the resistance, swimming, running, and running wheel exercise capacities of the rats were tested. The rats were administered treatment via tail vein injection, while the blank CON group received 0.9 % saline solution without treatment throughout the entire process. The results demonstrated a Tf-SSL CAF group encapsulation rate of 70.58 ± 5.14 %. Increasing the concentration of supplemented caffeine led to enhanced forelimb grip strength in rats, with significant differences observed in HCAF alone group, medium-dose Tf-SSL CAF (MTf-SSL CAF), and high-dose Tf-SSL CAF (HTf-SSL CAF) groups compared to the CON group. In the running and swimming experiments, higher caffeine supplementation concentrations correlated with increased running and swimming time to exhaustion, and the MTf-SSL CAF group showed longer running and swimming time compared to the HCAF alone group. The results of rat striatal dopamine levels indicated that increased caffeine supplementation concentrations led to higher dopamine secretion, with significantly different striatal concentrations in the HCAF group, MTf-SSL CAF group, and HTf-SSL CAF group compared to the CON group. The running wheel experiment revealed that rats in the medium- and high-dose Tf-SSL CAF groups exhibited greater 6-h running distances than the HCAF group and CON group. In conclusion, caffeine supplementation improved the physical performance of rats, with the high concentration CAF group outperforming the low and medium concentration groups. Furthermore, Tf-SSL CAF demonstrated superior physical enhancement compared to caffeine supplementation alone.

BACKGROUND: The aims of this cross-sectional study were to (a) assess actigraphy-based sleep parameters (total sample and gender differences), (b) assess differences in morphological parameters and physical function between short- versus normal-sleepers and poor- versus good-sleepers, and (c) assess the possible correlations between sleep variables and morphological and physical function parameters in older subjects.
METHODS: This study enrolled 42 healthy older participants (60-80 years). Participants completed the following clinical evaluations: (1) whole-body dual-energy X-ray absorptiometry to assess the appendicular skeletal muscle mass index; (2) magnetic resonance imaging acquisition to determine the cross-sectional muscle area of thigh muscles and intermuscular adipose tissue; (3) risk of fall assessment through the mini-Balance Evaluation Systems Test; (4) strength assessment: (a) chair stand test and (b) handgrip strength test; (5) sleep monitoring by actigraphy to assess total sleep time, sleep efficiency, wake after sleep onset, sleep latency, fragmentation index, mobile time, and subjective sleep quality.
RESULTS: 31.0% of subjects were short-sleepers (total sleep time < 6 hr), 19.1% were poor-sleepers (sleep efficiency < 85%), and gender differences were detected in mobile time (males: 15.8 ± 6.0 and females: 13.4 ± 6.8; p < .001) and fragmentation index (males: 35.3 ± 14.3 and females: 29.6 ± 14.6; p < .001); no significant differences were observed between groups (short- vs. normal-sleepers and poor- vs. good-sleepers) in morphological and physical function variables; correlation analysis showed that sleep latency negatively correlated with Mini-Balance Evaluation Systems Test (r = -.352; p = .022) and a positive correlation was detected between cross-sectional muscle area and mobile time (r = .349, p = .023).
CONCLUSIONS: No differences were observed in morphological and function parameters between good- versus poor-sleepers, those subjects with worse sleep onset latency (i.e., longer time to fall asleep) registered higher for risk of fall. The potential role of sleep in the physiological mechanisms of muscular aging must be explored through cross-sectional cohort studies with a larger population.

OBJECTIVE: Atrial fibrillation (AF) has been associated with functional impairment. However, the role exerted by AF on the long-term trajectories of functional mobility remains to be elucidated. This study aimed to evaluate the impact of AF on functional mobility by tracing walking speed (WS) trajectories over 15 years of follow-up in a population-based cohort of individuals aged 60+ years.
RESULTS: This population-based cohort study included 3141 community-dwelling participants (mean age 73.7 years; 63.6% women) from the Swedish National Study on Aging and Care in Kungsholmen, who were regularly examined from 2001-2004 to 2016-2019. Functional mobility was assessed by measuring WS in a standardized way. The association between AF and WS trajectories was assessed by multivariable joint models accounting for the longitudinal dropouts due to death. Stratified analyses by demographic and clinical factors were performed. The effect-modifying role of oral anticoagulant therapy (OAC), incident heart failure (HF), and incident stroke was finally investigated. At baseline, 285 (9.1%) participants were ascertained to have AF. A faster annual WS decline was observed in persons with AF than in non-AF peers (adjusted β coefficient per year = -0.011, 95% confidence interval: -0.016 to -0.005). Incident HF and stroke were associated with greater WS decline in participants with AF. OAC use was not associated with a slower functional decline.
CONCLUSIONS: Atrial fibrillation is associated with a faster physical function decline in older individuals. Incident HF and stroke possibly accelerate WS decline over time in AF participants.

OBJECTIVE: This study examined whether changes in late-life physical performance are associated with contemporaneous changes in blood pressure (BP) in older men.
METHODS: prospective cohort study over 7 years.
METHODS: Physical performance (gait speed, grip strength, chair stand performance) and clinic-measured BP at baseline and at least one follow-up (year 7 or 9) were assessed in 3,135 men aged ≥65 y enrolled in the Osteoporotic Fractures in Men Study (MrOS).
METHODS: Generalized estimating equation analysis of multivariable models with standardized point estimates (β [95% CI]) described longitudinal associations between physical performance and BP changes in participants overall, and stratified by baseline cardiovascular disease (CVD), antihypertensive medication use (none, ≥1), and enrollment age (<75 years; ≥75 years).
RESULTS: Overall, positive associations (z-score units) were found between each increment increase in gait speed and systolic (SBP) (0.74 [0.22, 1.26]) and grip strength (0.35 [0.04, 0.65]) or gait speed (0.55 [0.24, 0.85]) with diastolic (DBP). Better grip strength and chair stand performance over time were associated with 1.83 [0.74, 2.91] and 3.47 [0.20, 6.74] mmHg higher SBP, respectively in men with CVD at baseline (both interaction P < .05). Gait speed increases were associated with higher SBP in men without CVD (0.76 [0.21, 1.32]), antihypertensive medication non-users (0.96 [0.30, 1.62]), aged <75 years (0.73 [0.05, 1.41]) and ≥75 years (0.76 [0.06, 1.47]). Similar positive, but modest associations for DBP were observed with grip strength in men with CVD, antihypertensive medication non-users, and aged <75 years, and with gait speed in men without CVD, aged <75 years, and irrespective of antihypertensive medication use.
CONCLUSIONS: In older men, better physical performance is longitudinally associated with higher BP. Mechanisms and implications of these seemingly paradoxical findings, which appears to be modified by CVD status, antihypertensive medication use, and age, requires further investigation.

The loss of vestibular and motor function can occur naturally with aging. Vestibular physiotherapy exercises (VE) specifically address vestibular rehabilitation to reduce imbalances and improve physical condition, like therapeutic exercise (TE). During COVID-19, technology was used with the elderly for implementation. Objective: to determine if vestibular exercises are as effective as multicomponent exercises in improving functional capacity using technological tools. Methods: A randomized clinical trial compared two intervention groups of 21 subjects with functional limitations and frailty (average age 76.11 years). The intervention involved multicomponent exercise for the control group (Vivifrail protocol) and vestibular exercises for the experimental group (Cawthorne and Cooksey exercises) for 6 weeks with five sessions per week both groups. Two professionals implemented the exercises, and participants received tailored exercise videos. Primary outcomes were gait speed, dynamic balance, and physical capacity. Results: Both groups showed significant improvements. For physical function measured by SPPB (0-12 points), the multicomponent exercise group improved by 1.97 (0.91; 3.03), p < 0.001, and the vestibular exercise group improved by 1.63 (0.65; 2.60), p = 0.002. For dynamic balance measured by the Timed Up and Go (TUG) test, the multicomponent exercise group improved by -0.88 (-1.33; -0.42), p < 0.001, and the vestibular exercise group improved by -0.79 (-1.21; -0.37), p < 0.001. There were no significant differences between groups. Finally, regarding gait speed, there were no differences in either group between pretest and post-test (p > 0.05). Conclusions: Both multicomponent exercise and vestibular exercises improve functional capacities via telerehabilitation as measured by the SPPB, although vestibular physiotherapy does not show superior outcomes compared to the control group.

Increasing evidence shows that virtual reality (VR) training is highly effective in cognitive and motor rehabilitation. Another modern form of training is cognitive-motor dual-task training (CMDT), which has been demonstrated to rapidly improve physical and cognitive functions in real environments. This study aims to test whether a VR-based CMDT protocol can be used for motor and cognitive skill enhancement in young, healthy subjects. For this aim, 24 university students participated in a randomized control trial. The experimental group participated in a 5-week virtual reality reaction training (VRRT), performing 30 min sessions once a week. The control group did not receive any training but was tested twice with the same measures and temporal distance as the experimental group. Before and after the intervention, motor, cognitive, and electrophysiological measures were assessed. The results showed that following VRRT, the response time for both physical and cognitive tests was improved by about 14% and 12%, respectively, while the control group did not show significant changes. Moreover, electrophysiological data revealed a significant increase in anticipatory motor readiness in premotor brain areas in the experimental group only; however, cognitive top-down control tended to be increased in prefrontal areas after VRRT. This training protocol in a VR modality seems to be as effective as other CMDT methodologies carried out in a real modality. Still, it has the advantages of being more flexible and more user-friendly compared to standard training. The VRRT\'s efficacy on physical and cognitive functions indicates that virtual reality applications can be used by the young population, not only for entertainment purposes but also in the form of cognitive-motor training.

Mental fatigue has been studied extensively in relation to its impact on aerobic-, strength-, and motor-based tasks, but anaerobic power-based tasks have received limited attention. Interdisciplinary research investigating the underlying mechanisms by which mental fatigue influences physical performance has been called for. In two studies, the effects of mental fatigue on maximal power jump and endurance jump performance as well as kinetics and kinematics during jump performance were examined. Samples of collegiate volleyball players (Study 1; N = 14) and recreationally active students (Study 2; N = 27) completed two 30 min experimental manipulations (high vs. low cognitive control exertion) before performing three maximal power squat jumps followed by 15 repeated countermovement jumps, with measurements of kinetics and kinematics. For Study 1, the maximal power performance was significantly lower under a mentally fatigued condition, but no differences were observed for repeated jump performance, which may have been attributable to alterations in jump mechanics. For Study 2, no between-condition differences were observed for the maximal power performance, although repeated jump performance was significantly lower under a mentally fatigued condition. Collectively, these findings suggest that the impacts of mental fatigue on power-based performance tasks may depend on the task demands as well as the training status of the individual.

The aim of this study was to analyze the match-to-match variation in high-intensity demands from one Portuguese professional football team according to playing positions. Twenty-three male outfield professional football players were observed during eighteen matches of the Portuguese Second League. Time-motion data were collected using Global Positioning System (GPS) technology. Match running performance was analyzed based on the following three playing positions: defenders (DF), midfielders (MF), and forwards (FW). Repeated measures ANOVA was utilized to compare match running performance within each position role, and seasonal running variation. Practical differences were assessed using the smallest worthwhile change (SWC), coefficient of variation (CV), and twice the coefficient of variation (2CV). Significant differences were found among playing positions in total distance covered (F = 15.45, p < 0.001, η2 = 0.33), average speed (F = 12.79, p < 0.001, η2 = 0.29), high-speed running (F = 16.93, p < 0.001, η2 = 0.36), sprinting (F = 13.49, p < 0.001, η2 = 0.31), accelerations (F = 4.69, p = 0.001, η2 = 0.132), and decelerations (F = 12.21, p < 0.001, η2 = 0.284). The match-to-match running performance encompassed TD (6.59%), AvS (8.67%), HSRr (37.83%), SPR (34.82%), ACC (26.92%), and DEC (27.85%). CV values for total distance covered ranged from 4.87-6.82%, with forwards and midfielders exhibiting the greatest and smallest variation, respectively. Midfielders demonstrated the highest match-to-match variation for all other analyzed variables (8.12-69.17%). All playing positions showed significant variation in high-demanding variables (26.94-37.83%). This study presents the initial analysis of match-to-match variation in high-intensity demands within a Portuguese professional football team. Thus, the position\'s specificity and context can provide a helpful strategy for evaluating match-to-match running performance, and for recommending individualized training exercises based on the peak and high-intensity demands for each player\'s role within the game.

Physical activity is essential for healthy aging. This study aimed to identify an association between physical performance, body fat percentage (%BF), and the perception of oral health-related quality of life (OHRQoL) in independent older adults.
METHODS: A group of active older adults was selected from a government-sponsored reunion center in Mexico City. OHRQoL was assessed using the General Oral Health Index (GOHAI), and nutritional status was assessed using the Mini Nutritional Assessment (MNA) tool. A short physical performance battery (SPPB) was applied, and, for body composition, DXA (dual X-ray absorptiometry) was conducted. Data were analyzed using logistic regression models, and marginal probabilities were obtained.
RESULTS: This study involved 366 participants; their mean age was 73.9 (±6.2) years, and 24.9% had type 2 diabetes mellitus (T2DM). OHRQoL information revealed that pain or discomfort in the oral cavity was perceived by 63.9% of the older adults during the previous three months. The SPPB score was low in 159 (43.44%) participants. The logistic regression model revealed that age (OR = 1.13, p < 0.001), T2DM (OR = 2.10, p = 0.009), the risk of malnutrition/malnutrition (OR = 1.76, p = 0.047), high %BF (OR = 1.09, <0.001), and poor OHRQoL (OR = 1.96, p = 0.009) were associated with deteriorated physical performance.
CONCLUSIONS: OHRQoL self-perception, excess body fat, and nutritional status impacted physical performance. Aging well requires a comprehensive approach.

OBJECTIVE: The aim of this study was to investigate the longitudinal association of sleep with physical performance in a representative sample of non-institutionalised older adults residing in the municipality of São Paulo, Brazil.
METHODS: Prospective cohort study.
METHODS: The current longitudinal study used data extracted from the Health, Well-being, and Aging Study (Estudo Saúde Bem-Estar e Envelhecimento [SABE]). The study population consisted of individuals aged ≥60 years who participated in the study in 2010 or 2015. Dependent variables included the Short Physical Performance Battery (SPPB) and gait speed. Independent variables of interest were self-reported sleep difficulty, daytime sleepiness and sleep quality. The longitudinal association between sleep variables and the outcomes was evaluated using Generalised Estimating Equations (GEE) Models adjusted for covariates. All the variables, except age, sex and schooling, were assessed at baseline and follow-up visits (2010 and 2015).
RESULTS: The analyses included 2205 observations from 1559 individuals. The population mean age was 72 years in 2010 and 71 years in 2015, with a higher prevalence of women in both years. Between 2010 and 2015, there was a decline in the SPPB score and gait speed. Daytime sleepiness was negatively associated with the SPPB score [Coef.: -0.38 (95% confidence interval {CI}: -0.56, -0.21)] and gait speed [Coef.: -0.03 (95% CI: -0.05, -0.01)]. Poor sleep quality was negatively associated with the SPPB score [Coef.: -0.29 (95% CI: -0.57, -0.01)] and gait speed [Coef.: -0.03 (95% CI: -0.06, -0.00)].
CONCLUSIONS: Daytime sleepiness and poor sleep quality are associated with compromised physical performance in non-institutionalised older adults, and this association remained consistent over time.