Percorrer por autor "Malheiro, Alexandra"
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- Differential Effects of Low and High Caffeine Doses on Bench Press Muscular Endurance: A Randomized, Double-Blind, Placebo-Controlled Crossover StudyPublication . Saborosa, Guilherme Pereira; Leite, Luciano Bernardes; Forte, Pedro; Malheiro, Alexandra; Afonso, Pedro Miguel Vaz; Arruda, Dan Holz; Costa, Sebastião Felipe Ferreira; Souza, Helton de Sá; Silva, Sandro FernandesCaffeine contributes to improvements in physical performance by enhancing muscular strength and endurance. However, it is necessary to evaluate the effects of different dosages on resistance training (RT) performance. Therefore, this study aimed to compare the effects of different caffeine doses (i.e., 3 mg·kg−1 and 6 mg·kg−1) on the maximum number of repetitions in a muscular endurance test. The study included 11 male participants (25.7 ± 5.9 years) who completed six in-person visits. During the first visit, a 24 h dietary recall (24HDR) was administered, anthropometric measurements were assessed, and one-repetition maximum (1RM) was determined in the flat bench press (BP). The second visit (baseline; BL) included a new 24HDR, assessment of muscle thickness using portable ultrasound (pre- and post-test), and a muscular endurance test in the BP at 80% of 1RM performed until concentric failure. The four subsequent visits followed the same protocol, with the administration of caffeine or placebo capsules 60 min before testing in a randomized, double-blind manner: low-dose caffeine (3 mg·kg−1; LC), high-dose caffeine (6 mg·kg−1; HC), low-dose placebo (3 mg·kg−1; LP), and high-dose placebo (6 mg·kg−1; HP). The first three interventions were conducted with 48 h intervals, and the remaining interventions were separated by a 7-day interval. The number of repetitions and total workload (TWL) increased in all conditions compared with baseline; however, no significant differences were observed (p > 0.05). LC and HP achieved the highest repetition values (LC: 12.09 ± 3.33 reps; HP: 12.27 ± 2.72 reps). Muscle thickness was greater in all conditions in the post-test assessment, showing a significant increase (p < 0.05). Low- or high-dose caffeine supplementation appears to moderately influence responses in a muscular endurance test, suggesting that caffeine may be a potential supplement for resistance training.
- Exploratory Analysis of Physiological and Biomechanical Determinants of CrossFit Benchmark Workout Performance: The Role of Sex and Training ExperiencePublication . Malheiro, Alexandra; Forte, Pedro; Rodríguez-Rosell, David; Marques, Diogo L.; Marques, Mário C.CrossFit performance is influenced by physiological, neuromuscular, and perceptual factors, yet the extent to which these determinants vary by sex or training experience in standardized CrossFit Workouts of the Day (WODs) remains unclear. This study examined whether variables such as lactate accumulation, oxygen uptake dynamics, jump performance loss, and ventilatory responses relate differently to performance when stratified by sex and expertise. Fifteen trained athletes (eight males, seven females; overall mean age 27.7 ± 4.6 years) took part. Assessments included body composition, squat (SJ) and countermovement jumps (CMJ), and maximal oxygen consumption [VO2max]. On a separate day, they performed Fran (21-15-9 thrusters and pull-ups, Rx or scaled) The prescribed (‘Rx’) version used standardized barbell loads (43 kg for men, 29 kg for women), while the scaled version involved reduced loads or pull-up modifications. Respiratory gas exchange and heart rate were continuously monitored, while blood lactate and jump performance were measured pre- and post-WOD. Workout completion time [s] was the primary outcome. Correlation heatmaps explored associations in the overall sample and by sex and expertise. Mean completion time was 422.1 ± 173.2 s (range: 200–840). Faster performance correlated with higher ventilatory responses [ΔVe, r = −0.60, p = 0.018], greater mean VO2 (r = −0.62, p = 0.014), superior jump power [CMJ pre, r = −0.65, p = 0.009], and higher post-WOD lactate [r = −0.54, p = 0.036]. Sex-stratified analyses showed that males relied on ventilatory efficiency and neuromuscular power, whereas females were more constrained by performance loss and higher resting perceived exertion (RPE). Experts depended on ventilatory and neuromuscular efficiency, while initiates showed stronger associations with decrements in jump performance and higher RPE. These findings highlight subgroup-specific performance profiles and reinforce the need for tailored training strategies in CrossFit athletes.
- Exploratory Analysis of the Correlations Between Physiological and Biomechanical Variables and Performance in the CrossFit® Fran Benchmark WorkoutPublication . Malheiro, Alexandra; Forte, Pedro; Rosell, David Rodríguez; Marques, Diogo L.; Marques, Mário C.The multifactorial nature of CrossFit performance remains incompletely understood, particularly regarding sex- and experience-related physiological and biomechanical factors. Fifteen trained athletes (8 males, 7 females) completed assessments of anthropometry, estimated one-repetition maximums (bench press, back squat, deadlift), squat jump (SJ), maximal oxygen uptake (VO(2)max), ventilatory responses ( V E-center dot), and heart rate (HR). Spearman, Pearson, and partial correlations were calculated with Holm and false discovery rate (FDR) corrections. Males displayed greater body mass, lean and muscle mass, maximal strength, and aerobic capacity than females (all Holm-adjusted p < 0.01). Experienced athletes completed Fran faster than beginners despite broadly similar anthropometric and aerobic profiles. In the pooled sample, WOD time showed moderate negative relationships with estimated 1RM back squat (rho = -0.54), deadlift (rho = -0.56), and bench press (rho = -0.65) before correction; none remained significant after Holm/FDR adjustment, and partial correlations controlling for training years were further attenuated. This exploratory study provides preliminary evidence suggesting that maximal strength may contribute to Fran performance, whereas conventional aerobic measures were less influential. However, given the very small sample (n = 15, 8 males and 7 females) and the fact that no relationships remained statistically significant after correction for multiple testing, the results must be regarded as preliminary, hypothesis-generating evidence only, requiring confirmation in larger and adequately powered studies.
- Impact of physical exercise interventions on functional fitness in older adultsPublication . Chen, Cheng; Freire, Cristiana; Fu, Zhiyang; Teixeira, Inês; Adegas, Matilde; Gomes, Rafael; Rabaçal, Ricardo; Silva, Sara; Malheiro, Alexandra; Leite, Luciano Bernardes; Reis, António; Monteiro, António M.; Yang, Jing; Xiaolin, Yao; Forte, PedroAging is associated with a decline in functional fitness, compromising the autonomy of older adults. This systematic review evaluated recent randomized clinical trials (2015–2024) on the effects of physical exercise in individuals aged ≥65 years. Ninety-five studies were included, showing that multicomponent programs, resistance training, and supervised protocols improved muscular strength, mobility, balance, gait speed, and body composition. Interventions lasting more than 12 weeks with high adherence yielded more favorable outcomes. Effects on cognitive function were inconsistent. Structured exercises tailored to the capacities of older adults are effective strategies to promote functional independence and healthy aging, although study heterogeneity limits some conclusions.
- Literary tourism in northern portugal: an exploratory perspectivePublication . Sousa, Bruno; Liberato, Pedro; Liberato, Dália; Pereira, Carina; Rodrigues, Cristina; Costa, Adriano; Malheiro, Alexandra; Esteves, Elsa Tavares; Carvalho, PedroThe present study intends to structure a tourist offer based on literary tourism, with the proposal of literary routes in the Northern region of Portugal, in particular the municipalities covered by the Regional Tourism Authority - Entidade Regional de Turismo do Porto e Norte (ERTPNP), through the dynamisation of its literary heritage and its socio-cultural stimulation. It is expected to contribute to the promotion of tourism policies oriented to the development of new products and experiences, based on the identity and specificities of the different territories involved, with relevant authors and works. In addition, it is expected to develop a prototype of an APP for the promotion and dynamisation of one of the literary routes, the most representative of the literary heritage of the region which will provide an immersive and rich experience. A process that will involve the different stakeholders.The project aims to create a territorial database where a literary tourism development model can be applied through tourist routes. The criteria for applying the methodology will be based on: Cultural value of literary activities and their attractiveness to visitors; Literary nature of activities offered; Benefits for the local community; Involvement of the local community in the design of literary experiences; Relationship between visitors, local producers, and the local community; Use of local resources for the development of literary experiences; Use of digital techniques to develop engaging and participatory experiences.
- Machine learning prediction of adolescent obesity using physical fitness dataPublication . Sampaio, Tatiana; Encarnação, Samuel; Amaro, Bruna; Ribeiro, Joana; Branquinho, Luís; Monteiro, António M.; Teixeira, José Eduardo; Hattabi, Soukaina; Sortwell, Andrew; Leite, Luciano Bernardes; Malheiro, Alexandra; Rodrigues, Pedro M.; Beat Knechtle; Flores, Pedro Miguel; Forte, PedroThe escalating prevalence of obesity among adolescents has emerged as a critical global public health challenge. Machine learning techniques have been used to predict obesity in adolescents. This study aimed to develop and validate a robust obesity prediction model for adolescents using this hybrid approach, leveraging data from a diverse cross-sectional population-based study. The hybrid method combines statistical inference with non-linear machine learning to enhance prediction accuracy. Physical fitness data were collected from the FITescola® tests. Multiple tests were employed to evaluate physical fitness. Multiple Poisson's multiple regression method was applied to identify the most predictive variables set of the adolescent's body mass index (BMI) classification. The model's goodness-of-fit statistics indicate a strong fit, with a log-likelihood of 8068.6 and a Pseudo R-squared value of 0.8853, where the aerobic fitness (AF), upper limb strength (ULS) and lower limb flexibility (LLF) presented an inverse association with the adolescent's BMI. In contrast the adolescent's core strength presented a positive association with their body mass. The random forest regression showed that an average of 35 repetition on the yo-yo test predicted a healthy BMI percentile [predBMIperc = 0.31]. In addition, the model presented good validity [MAE = 0.36, MSE = 0.20, RMSE = 0.45, R2 = 0.54]. The model's strong fit and accurate random forest regression's predictions suggest that physical fitness components, such as aerobic fitness, upper limb strength, lower limb power, and core strength, play a significant role in obesity risk among adolescents.
- Motivations of literary tourism in northern PortugalPublication . Esteves, Elsa Tavares; Costa, Adrinano; Carvalho, Pedro; Pereira, Carina; Lourenço, Cristina; Malheiro, Alexandra; Liberato, Dália; Liberato, Pedro; Sousa, BrunoThe purpose of this study is to identify the motivations of literary tourism consumers in the northern region of Portugal. The aim of this information is to contribute to the development of literary routes and the promotion of the region's cultural and literary heritage. We hope to contribute to the promotion of tourism policies geared towards the development of new products and experiences, based on the identity and specificities of the different territories involved, with relevant authors and works.
- Perception of satisfaction with body image in adolescents from Paredes Secondary SchoolPublication . Flores, Pedro Miguel; Malheiro, Alexandra; Monteiro, A.M.Body image is part of the mechanism of personal identity that can be given as a mental representation of the body itself, reflecting the way individuals think, feel, and behaves in relation to their physical appearance. The perception of an individual’s body image changes due to intrinsic and extrinsic factors and, in adolescence, due to the formation of their identity, the influence of social media and network can be very determinant in their body image perception that have beauty and aesthetics standards difficult to achieve. Sports physical activity (SPA) proves to be a way to maintain or achieve the ideal physical shape, thus it increases the body satisfaction and the perception of body image (PSIC). The main objective of the current study is to evaluate the relationship between the practice of AFD and PSIC in adolescence, Paredes high school. It was concluded that the perception and satisfaction of body image varied according to the practice of physical sports activity in male students. In females, the practice of sports physical activity did not influence the perception and satisfaction of their body image.