Jorge E Morais

• PhD
• Adjunt Professor at Polytechnic Institute of Bragança

This study aimed to compare the aerodynamics of a shoulder amputee cyclist through computational fluid dynamics (CFD) and mathematical models. The geometry of the cyclist-bicycle system was collected by a Sense 3D scanner. The boundaries around the bicycle-cyclist system were defined on Ansys Workbench software. The velocities were set between 1 an...

Studies about drag in swimming usually report or put the focus on its absolute value. However, it is being claimed that the drag coefficient better represents the hydrodynamic profile of a swimmer. Drag is strongly dependent on speed. Thus, increases in speed will lead to increases in drag. This could lead to misleading interpretations since drag i...

The aim of this study was to conduct a scoping and bibliometric review of articles using artificial intelligence (AI) in tennis. The analysis covered various aspects of tennis, including performance, health, match results, physiological data, tennis expenditure, and prize amounts. Articles on AI in tennis published until 2024 were retrieved from th...

This study aimed to analyse the aerodynamics by numerical simulations with computer fluid dynamics of an able-bodied cyclist and a shoulder-amputee cyclist. An elite cyclist volunteered for this research; the cyclist was scanned with his competition gear and bicycle and the able-bodied and shoulder amputee 3D cyclists models were created. Numerical...

The purpose of this study was to compare the effects of on-court tennis training (OTT) combined with high-intensity interval training (HIIT) or repeated sprint training (RST) on the physiological, kinematic, kinetic, and perceptual responses of young tennis players. Twenty-four male tennis players (age 13.6 ± 0.3 years) were randomly assigned to ei...

The aging process is often described as a decline in physical strength and balance due to biological and psychological factors, leading to an increased risk of falls among the elderly. This brief review aims to resume on a solid basis the influence of resistance training on the risk of falling in elderly people. Seven studies were analyzed regardin...

Competitive swimming, often seen as a rigorous sport, has profound impacts in the physical well-being of athletes and on their mental health. It demands high levels of dedication and resilience, which can sometimes lead to psychological challenges such as depression, anxiety, and burnout. This brief review aims to resume on a solid basis the impact...

Background The step test provides valuable information on cardiorespiratory parameters such as maximal oxygen uptake and heart rate. Cardiorespiratory capacity is critical to health-related fitness, with heart rate recovery after exercise serving as a predictor of mortality risk. Main Body The primary objective of this review was to identify trend...

This study clarified changes in arm stroke coordination during assisted swimming. Fourteen male collegiate swimmers swam 25-m front crawls with (A-swim with towing device) and without an assist (N-swim) at a submaximal to maximum (slow, moderate, and fast) effort. Swimming velocity (v), stroke frequency (SF), stroke length (SL), and stroke coordina...

The power output in cycling is one of the most important factors for athletes and coaches. The cycling community has several commercial gears that can be used. One of the most used is the TACX Neo 2T (TN2T) smart trainer. The objective of this study was to investigate the metrological proprieties of the TN2T (accuracy and reliability), as well as i...

The aim of this study was to compare swimming speed and speed fluctuations in front crawl between swimmers of different performance levels using discrete variables against statistical parametric mapping (SPM). The sample was composed of 34 male swimmers divided into three groups: (i) group #1-recreational swimmers; (ii) group #2-competitive swimmer...

Futsal carries a high risk of injury for players. This systematic review aimed to assess the existing literature on injury prevention strategies for futsal players. The literature was searched using PubMed, Web of Science, and Scopus databases from inception to 20 March 2024. Relevant articles were searched using the terms "futsal" AND "injury" AND...

1) Background: Tennis has changed toward power-driven gameplay, demanding a nu-anced understanding of performance factors. This review explores the role of machine learning in enhancing tennis performance. (2) Methods: A systematic search identified articles utilizing machine learning in tennis performance analysis. (2) Results: Machine learning ap...

The aim of this study was to conduct a scoping and bibliometric review of swimming articles related to race analysis. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used to identify relevant studies. Articles on race analysis in swimming published between 1984 and December 31, 2023 were retrieved fro...

The study aimed to (i) verify the effects of an on-court training program on the International Tennis Number (ITN) of young tennis players, as well as on a set of change of direction, linear sprint, and maximal oxygen uptake (VO2max) variables, and (ii) identify the main predictors of ITN. The sample consisted of 20 young male tennis players (mean...

The aim of this study was to verify the accuracy of predicting oxygen consumption (O2) in predominantly aerobic activities based on net heart rate (netHR), sex, and body mass index (BMI) in active adults. NetHR is the value of the difference between the resting HR (HRrest) and the average HR value obtained during a given session or period of physic...

Despite the numerous scientific evidence on the topic, there is no clear and consistent answer that clarifies the true effects of beetroot juice (BJ) supplementation on different types of physical performance. This study examined whether an acute intake of BJ improves swimming performance, physiological variables of anaerobic metabolism, or subject...

The butterfly stroke stands out as a highly technical and demanding stroke that heavily relies on the coordinated movement of the upper limbs. The aim of this study was to compare the propulsion between upper limbs in young swimmers in the butterfly stroke through Statistical Parametric Mapping (SPM). The sample consisted of 10 young national level...

Cardiovascular capacity, expressed as maximal oxygen uptake (VO2max), is a strong predictor of health and fitness and is considered a key measure of physiological function in the healthy adult population. The aim of this study was to investigate the influence of the physical activity levels (PA level) of participants in the StepTest4all (validated...

The aim of this study was to understand the interactions between anthropometric, kinetic, and kinematic variables and how they determine the 100 m freestyle performance in young swimmers. Twenty‐five adolescent swimmers (15 male and 10 female, aged 15.75 ± 1.01 years) who regularly participated in regional and national competitions were recruited....

Citation: Magalhães, P.M.; Cipriano, F.; Morais, J.E.; Bragada, J.A. Effects of a 16-Week Training Program with a Pyramidal Intensity Distribution on Recreational Male Cyclists. Sports 2024, 12, 17. https://doi. Abstract: Different training intensity distributions (TIDs) have been proposed to improve cycling performance, especially for high-competi...

Dynamic balance and ankle dorsiflexion are associated with performance and injury risk in young athletes. The aim of this study was to characterize lower limb dynamic balance and ankle dorsiflexion in young futsal players and to understand their relationships. Eighteen young male futsal players (with 15.2 ± 1.2 years of age and with a right lower l...

Comparative analysis of cyclist energy cost and drag: able-bodied vs. shoulder amputee cyclists using computational fluid dynamics ABSTRACT In cycling, drag is the force that opposes the cyclist's motion and is caused by the cyclist's and their equipment's interaction with the air. The surface area of the cyclist and their equipment, such as the bi...

In sports, coaches and support staff spend considerable time analyzing athletes’ technique. [...]

Introduction The aim of this study was to explore which key somatic features are common to four swim strokes and medley, and specifically to identify which characteristics benefit only specific strokes. Methods The sample was composed of 130 swimmers (95 males aged 19.5 ± 2.9 years and 35 females aged 18.4 ± 2.8 years). A set of anthropometric var...

Background and objectives: Pilates training intervention programs have gained attention as a potential approach to enhancing balance in older adults, thereby reducing the risk of falls. In light of these considerations, this systematic review and meta-analysis aimed to critically evaluate the existing evidence and determine the effect of Pilates t...

Resisted sled sprint (RSS) is a traditional sprint training in which a variety of loads are used for multiple aims. Nevertheless, a detailed analysis of the effects of different loads has not yet been performed. Therefore, this study aimed to examine the effects of load differences on running velocity, step frequency, and step length during RSS in...

The main objective of this study was to confirm that the passive drag coefficient is less dependent on swimming speed than the passive drag, Froude, and Reynolds numbers, even as swimming speed increases. The sample consisted of 12 young proficient non-competitive swimmers (seven males and five females: 20.4 ± 1.9 years). Passive drag was measured...

Relação entre o coeficiente de arrasto passivo e ativo na técnica de crol. Certificado: 2º lugar - Treino desportivo e performance

The purpose of this study was to investigate the relationship between swimming speed, intra-cycle variation of horizontal speed of displacement ( dv ), and Froude efficiency (η F ) in front-crawl during three consecutive stroke cycles. The sample consisted of 15 boys aged 16.07 ± 0.77 years and 15 girls aged 15.05 ± 1.07 years. Swimming speed, dv a...

This study aimed to: (i) verify the within-subject effect of the dominant and non-dominant upper limb propulsion during consecutive arm-pulls through discrete (average) and continuous analysis (SPM), and; (ii) compare young swimmers' propulsion between both upper limbs through discrete (average) and continuous analysis (Statistical Parametric Mappi...

Literature lacks evidence about the physiological recovery of tennis players between points. This study aimed to: (i) verify the heart rate (HR) and oxygen uptake (V̇O2) recovery variance in young tennis players from the end of a tennis drill until the 25-s mark and onwards (65-s limit), performed at several intensities, and (ii) test the curve fit...

The aim of this study was to compare the swimming velocity in front-crawl between age-group swimmers using discrete variables against Statistical Parametric Mapping (SPM). The sample consisted of 30 young male swimmers divided into three groups (each with 10 swimmers) based on their age (group #1: 13.60 ± 0.84 years; group #2: 15.40 ± 0.32 years; g...

Purpose: The aim of this study was to assess the interaction of kinematic, kinetic, and energetic variables as speed predictors in adolescent swimmers in the front-crawl stroke. Design: Ten boys (mean age [SD] = 16.4 [0.7] y) and 13 girls (mean age [SD] = 14.9 [0.9] y) were assessed. Methods: The swimming performance indicator was a 25-m sprin...

Objectives The aim of this study was to cluster U-14 Portuguese regional team football players based on variables related to lower limb strength and power, dynamic balance, linear sprint, and change of direction. Method The sample consisted of 22 young male soccer players (13.83 ± 0.44 years). A set of variables related to lower limb strength and...

Besides recurrently assessed water-based parameters, there are also some individual characteristics that affect swimming performance that are not water related. In the past few years, dynamic balance has been associated with land sports performance. Conversely, evidence on this topic in swimming is scarce. The purpose of this study was to assess th...

Swimming is a time-based sport and hence strongly dependent from velocity. Most studies about swimming refer to velocity as discrete variable, i.e., 0-D (no time dimension). However, it was argued that using swimming velocity as a continuous variable (1-D, with time dimension) with Statistical Parametric Mapping (SPM) can bring deeper and detailed...

The aim of this study was to compare the assessment of swimming speed processed as a discrete variable and as a continuous variable in young swimmers. One-hundred and twenty young swimmers (60 boys: age = 12.91 ± 0.86 years; 60 girls: age = 12.46 ± 0.94 years) were analysed. The dataset for each sex was divided into three tiers: (i) tier #1 - best-...

Drag crisis has been described as a drop in the drag coefficient (Cd). This procedure was lately assessed in able-bodied cyclists in time trial position by computational fluid dynamics (CFD). Therefore, the aim of this study was to assess the phenomenon of the drag crisis by computer fluid dynamics in transradial and transtibial amputee cyclists in...

Evidence on the role of propulsion compared to drag in swimming, based on experimental settings, is still lacking. However, higher levels of propulsion seem to lead to faster swimming velocities. The aim of this study was to understand the variation in a set of kinematic and kinetic variables between two swimming sections and their relationship to...

This study aimed to understand whether there are significant differences in stroke kinematics between tiers in female swimmers competing in the four 50 m events of the 2021 European Championships and to understand the speed-time relationship in the four race events per tier. Participants were all female swimmers (backstroke: 78 swimmers; breaststro...

The aims of this study were to: (1) analyze and compare the stroke kinematics between junior and senior elite male swimmers in every section of the race during the 50-m freestyle event, and; (2) identify stroke frequency (SF)–stroke length (SL) combinations on swim speed independently for junior and senior swimmers in each section of the 50-m frees...

This study aimed to: (i) present normative data of the variables related to the start in the four swim strokes by tier and sex, and; (ii) understand the relationship between the 15 th meter mark time and the final race time of the male and female swimmers competing in the four 50 m events at the 2021 European Championships. Participants were all ma...

The aim of this study was to analyze the agreement of the active drag coefficient measured through drag and propulsion methods. The sample was composed of 18 swimmers (nine boys: 15.9 ± 0.9 years; nine girls: 15.3 ± 1.2 years) recruited from a national swimming team. The velocity perturbation method was used as the drag measurement system and the A...

Avaliar e controlar as mais diversas variáveis no âmbito dos estudos na área das ciências do desporto permite a melhoria dos resultados, o aumento da competitividade e extrapolar os limites do conhecimento. Em desportos em que o tempo final e a velocidade são o fator principal da performance, a minimização da resistência desempenha um papel fundame...

Background Smart technology, such as wearables, applied to sports analysis is essential for the performance enhancement. New technological equipment can promote the interaction between researchers, coaches, and athletes, facilitating the information exchange in real-time. Objective The aim of this study was to present a new wearable equipment (Sma...

The aims of this study were to (i) verify the relationship between reserve oxygen uptake (VOreserve) and reserve heart rate (HRreserve) in young male tennis players, and (ii) understand the relationship between oxygen uptake (VO2) measured at the end of a tennis drill and recovery heart rate (HRrecovery) after the tennis drill. Ten young male tenni...

Understanding the difference in each upper limb between age groups can provide deeper insights into swimmers’ propulsion. This study aimed to: (1) compare swimming velocity and a set of kinematical variables between junior and juvenile swimmers and (2) compare the propulsion outputs through discrete and continuous analyses (Statistical Parametric M...

Introduction: In swimming, it is necessary to understand and identify the main factors that are important to reduce active drag and, consequently, improve the performance of swimmers. However, there is no up-to-date review in the literature clarifying this topic. Thus, a systematic narrative review was performed to update the body of knowledge on a...

The aim of this study was to: (i) characterise the stroke kinematics’ stability of the male swimmers competing in the four 50 m events at the 2021 European Championships, and; (ii) understand the speed–time relationship in the four race events. All male swimmers who participated in the 50 m events (backstroke: 78 swimmers; breaststroke: 79 swimmers...

Purpose The drag in walking, running, and sprinting locomotion can be assessed by analytical procedures and experimental techniques. However, assessing the drag variations by these three main locomotion’s (i.e., walking, running, and sprinting) were not found using computational fluid dynamics. (CFD). Thus, the aim of this study was two-fold: (1) t...

Background: Cardiovascular capacity, expressed as maximal oxygen uptake (VO2max), is a strong predictor of health and fitness and is considered a key measure of physiological function in the healthy adult population. The purpose of this study was to validate a specific step test (StepTest4all) as an adequate procedure to estimate cardiovascular ca...

Background: In the present study, we aimed to clarify the impact of the Assisted swim (A-swim; towing from propulsion direction) on front crawl performance at maximum and sub-maximum effort levels. Methods: Fourteen male collegiate swimmers (age, 21.0 ± 2.0 years; height, 1.73 ± 0.05 m; weight, 67.1 ± 7.1 kg) participated. Participants swam 25-m fr...

Physical activity plays a paramount role on children growth and schools emerged as a key setting for promoting physical activity during childhood. The aim of this study was to verify the effects of a high intensity circuit training performed during regular physical education classes at schools. One hundred and five children aged 11-14 years (71 boy...

Nowadays, wearables are a must-have tool for athletes and coaches. Wearables can provide real-time feedback to athletes on their athletic performance and other training details as training load, for example. The aim of this study was to systematically review studies that assessed the accuracy of wearables providing real-time feedback in swimming. T...

The aim of this study was to classify and identify young swimmers' performance, and biomechanical determinant factors, and understand if both sexes can be clustered together. Thirty-eight swimmers of national level (22 boys: 15.92 ± 0.75 years and 16 girls: 14.99 ± 1.06 years) were assessed. Performance (swim speed at front crawl stroke) and a set...

Introduction: This study aimed to: 1) determine swimming velocity based on a set of anthropometric, kinematic, and kinetic variables, and; 2) understand the stroke frequency (SF)–stroke length (SL) combinations associated with swimming velocity and propulsion in young sprint swimmers. Methods: 38 swimmers (22 males: 15.92 ± 0.75 years; 16 females:...

This study aimed to (i) compare the race performance of the swimmers with better performances and poorer performances during all sections of a 100 m freestyle event and (ii) compare stroke kinematics variables between tiers and analyse their stability in each tier. The sample was composed of 88 swimmers that participated in the 100 m Freestyle even...

Understanding the factor weighting in the development of metabolic syndrome (MetS) may help to predict the progression for cardiovascular and metabolic diseases. Thus, the aim of this study was to develop a confirmatory model to describe and explain the direct and indirect effect of each component in MetS status change. A total of 3581 individuals...

Wheelchair racing is one of the most important sports in the Paralympics. The detailed analysis of all parameters is of great importance to achieve sporting excellence in this modality. In wheelchair racing, resistive and propulsive forces determine the movement of the athlete-wheelchair system. Most of propulsive forces are generated by the streng...

Background When in water, the Centers of Buoyancy (CoB) and Mass (CoM) of the human body are positioned cranially and caudally, respectively. With increasing distance between these centers, the sinking torque of the lower limbs increases, with a subsequent decrease in swimming performance due to increased drag. Objective To clarify the effect of a...

The aim of this study was to: (1) analyze and compare the race performance and stability between the fastest and slowest male swimmers during the 50 m freestyle event, and; (2) to understand the speed-time relationship in this race. The performances (start, clean swim, and finish) of 86 swimmers (divided into two tiers: best and poorest performance...

Introduction: In youth swimming, researchers are interested in understanding how anthropometry and parameters related to swimming technique (biomechanics, energetics, and efficiency) influence the performance. However, there is not any review in the literature that consolidates the body of knowledge of this topic. The objective of this study was to...

Retos, número 43, 2022 (1º trimestre)-316-Learn-to-swim program in a school context for a twelve-week period enhance aquatic skills and motor coordination in Brazilian children Las clases de natación en el contexto escolar durante un período de doce semanas mejoran las habilidades acuáticas y la coordinación motora en niños brasileños Abstract. Thi...

The aim of this study was to: (1) verify differences between swimmers of the same competitive level in variables related to the start and finish (50 m and 100 m freestyle); (2) verify if starting and finish variables are responsible for faster race time, and which starting variables are responsible for the start performance in such events. For the...

The aims of this study were to: (1) assess the stability (mean and normative) of the lap performance, and a set of clean swim and turn variables of junior male swimmers in the 200 m freestyle, and; (2) verify the relationship between the start, clean swim, turn, and finish phases in the 200 m freestyle. Seventy-six individual races in the 200 m fre...

This study aimed to verify the effects of 12 weeks of swimming lessons implemented in age school Brazilian children’s aquatic skills and motor coordination. Fifty children aged 6 to 10 years old (mean ± SD: 8.34 ± 1.10 years), participated in one swimming lesson per week provided by the school curriculum. Each child was evaluated for their aquatic...

The aim of this study was to assess and compare by numerical simulations and analytical models the resistive forces, mechanical power, energy cost and velocity using two different types of road helmets (standard vs aero road helmet). An elite cyclist was scanned on the racing bicycle, wearing his competition gear and helmets. Numerical simulations...

The aims of this study were to: (1) verify the sex effect; (2) assess upper limb asymmetry in anthropometrics and propulsive force variables; and (3) identify the main determinants of butterfly swim velocity based on a set of anthropometrics, kinematics, and propulsive force variables. Twenty swimmers (10 males: 15.40±0.30 years; 10 females: 14.43±...

The aim of this study was to assess elderly’s functional fitness and body composition effects between pre and post multicomponent training program with six months of intervention. The sample of this study was composed with 34 volunteered elderlies with 68 (± 7.55) years old. The body composition was evaluated with a Tanita BC-545 and functional fit...

The aim of this study was to compare the aerodynamics of able-bodied and amputee cyclists by computational fluid dynamics. The cyclists’ geometry was obtained by a 3D scanner. Three CAD models were created as able-bodied, transtibial (Tt), and transradial (Tr) amputees. Numerical simulations were conducted up to 13 m/s with increments of 1 m/s to a...

Forte et al. Postural Asymmetries in Soccer-Rev Bras Futebol 2020; v. 13, n. 3, 03-16. ANÁLISE DA MAGNITUDE DAS ASSIMETRIAS POSTURAIS EM CRIANÇAS E JOVENS FUTEBOLISTAS RESUMO Introdução: As assimetrias posturais estão relacionadas a diferentes tipos de lesões. Com isso, o controlo postural pode prever problemas dor ou ruturas musculares. Além disso...

Resumo O objetivo deste estudo foi avaliar o arrasto, a potência mecânica e a performance de um ciclista de elite na posição vertical, dropes e de cotovelos com um capacete normal com recurso a simulações numéricas e modelos analíticos. O FD variou entre 19,67 N e 25,15 N, a potência mecânica total variou entre 308,12 W e 370,49, o custo energético...

Although swimming is a sport usually practiced by children, little knowledge exists about its effect on motor developmem This study aimed to evaluate and compare the gross motor development in children ofdifferent ages with or without regular swimmin practices. 116 children (58 males, 58 females) aged between 5 to 10 years old, distributed in two g...

This study aimed to analyse the stability of elite male long-distance swimmers (1500 m), and to identify the main predictors related to the pace. The performance of 16 elite male swimmers (22.59 ± 2.10 years-old) participating in the 1500 m event at the 2016 (London) and 2018 (Glasgow) LEN European Aquatic Championships were analysed. The lap perfo...

The purpose of this study was to understand the relationship between the coaches’ demographics (academic degree and/or coaching level and/or coaching experience) and young swimmers’ performance and technical ability. The sample was composed by 151 young swimmers (75 boys and 76 girls: 13.02 ± 1.19 years old, 49.97 ± 8.77 kg of body mass, 1.60 ± 0.0...

Abstract Short-distance swimmers may exhibit imbalances in their upper-limbs’ thrust (differences between the thrust produced by each upper-limb). At maximal speed, higher imbalances are related to poorer performances. Additionally, little is known about the relationship between thrust and swim speed, and whether hypothetical imbalances exist in th...

The drag crisis phenomenon is the drop of drag coefficient (Cd) with increasing Reynolds number (Re) or speed. The aim of this study was to assess the hypothetical drag crisis phenomenon in a sports setting, assessing it in a bicycle-cyclist system. A male elite-level cyclist was recruited for this research and his competition bicycle, helmet, suit...

The main aim of this study was to compare the start, turn, and finish performance of 100 m and 200 m events in the four swimming strokes in elite swimmers of both sexes. The performances of all 128 finalists (64 males and 64 females) of the 100 m, and 200 m events at a major championship were analyzed. A set of variables related to the start, turn,...

The aim of this study was to use numerical simulations and analytical procedures to compare a cyclist's performance in three different cycling positions. An elite level road cyclist competing at a national level was recruited for this research. The bicycle was 7 kg and the cyclist 55 kg. A 3D scan was taken of the subject on the competition bicycle...

Background and Objectives: The aim of this study was to assess and compare the drag and energy cost of three cyclists assessed by computational fluid dynamics (CFD) and analytical procedures. Materials and methods: A transradial (Tr) and transtibial (Tt) were compared to a full-body cyclist at different speeds. An elite male cyclist with 65 kg of m...

Background: Resistance acting on a cyclist is a major concern among the cycling fraternity. Most of the testing methods require previous training or expensive equipment and time-consuming set-ups. By contrast, analytical procedures are more affordable and numerical simulations are perfect for manipulating and controlling inputs. The aim of this ca...