Filipe Conceicao

University of Porto | UP

The aims of this study were to assess (i) the load–velocity relationship during the box squat exercise in women survivors of breast cancer, (ii) which velocity variable (mean velocity [MV], mean propulsive velocity [MPV], or peak velocity [PV]) shows stronger relationship with the relative load (%1RM), and (iii) which regression model (linear [LA]...

Jumping performance is considered an overall indicator of gymnastics ability. Acrobatic Gymnastics involves base and top gymnasts, considering the type of training that is performed and the distinct anthropometric traits of each gymnast. This work aims to investigate a hierarchy of variables that influence the force–velocity (F-V) profile of top an...

The literature on motor development and training assumes a hierarchy for learning skills—learning the “fundamentals”—that has yet to be empirically demonstrated. The present study addressed this issue by verifying (1) whether this strong hierarchy (i.e., the proficiency barrier) holds between three fundamental skills and three sport skills and (2)...

An increased jumping performance is key for gymnastics competition routines. Rhythmic gymnasts (RGs) use the jump as one of the main body elements. In Acrobatic Gymnastics (ACRO), top gymnasts must coordinate their jumps with the impulse provided by base gymnast(s). It is expected that the gymnasts' discipline and role played impact their jumping s...

The aim of this study was to determine the muscle co-activations and joint stiffnesses around the hip, knee, and ankle during different walking speeds and to define the relationships between muscle co-activation and joint stiffness. Twenty-seven healthy subjects (age: 19.6 ± 2.2 years, height: 176.0 ± 6.0 cm, mass: 69.7 ± 8.9 kg) were recruited. Mu...

Since acrobatic gymnastics is a recent, only a few decades old gymnastics discipline, it is not yet much explored as a scientific research field. Despite its increasing popularity, and while science mapping has become an essential activity for all scientific disciplines, no bibliometric analysis on this topic was available. Therefore, this study ai...

The biomechanical analysis of Acrobatic Gymnastics elements has not been extensively explored in scientific research to date. Due to the increased challenge of implementing experimental protocols and collecting data from multiple individuals, it is required to develop strategies that allow a safe, valid and reproducible methodology. This work aims...

Dancers require many specific dance skills of a ballistic nature. The design of supplementary training to improve the strength of the lower limbs and jump height is a relevant area of research. The purpose of this study was (1) to compare the effect of plyometric training versus combined training on countermovement jump (CMJ), squat jump (SJ), and...

The aim of this study was to analyze the influence of age and sex on kinematic gait parameters in preschool children, and derive reference values for this population. A total of 383 preschool children (age 3–5 years; 207 girls, 176 boys) participated in this study. We used the OptoGait system to assess the kinematics of gait at a comfortable and se...

Patellofemoral pain syndrome (PFPS) is highly prevalent; it can cause severe pain and evolve into progressive functional loss, leading to difficulties performing daily tasks such as climbing and descending stairs and squatting. This systematic review aimed to find evidence, in the literature, of squat movements that can cause or worsen PFPS. This w...

Dancers require many specific dance skills of a ballistic nature. The design of supplementary training to improve the strength of the lower limbs and jump height is a relevant area of research. The purpose of this study was (1) to compare the effect of plyometric training versus combined training on countermovement jump (CMJ), squat jump (SJ), and...

Jumping ability is considered a determinant of performance success. It is identified as one of the predictors and talent identification in many sports and dance. This study aimed to investigate the effect of 16 weeks of lower-limb strength training on the jumping performance of ballet dancers. A total of 24 participants from the same dance school w...

This study aims to comprehensively assess the accuracy and precision of five different devices and by incorporating a variety of analytical approaches for measuring countermovement jump height: Qualisys motion system; Force platform; Ergojump; an Accelerometer, and self-made Abalakow jump belt. Twenty-seven male and female physical education studen...

Despite the controversy surrounding periodization, it has been assumed over the years as the key tool in training planning for the development and achievement of high-level performance, in individual sports. Given the enormous density of nowadays competitive calendar and the athletes’ responsibilities towards their sponsors, the challenge is to tra...

Netball is a collective sport characterized by intermittent high-intensity actions. Therefore, the players must develop high levels of relative bilateral and unilateral strength and power for both improve performance and also reduce injury risk. The purpose of this study was (i) to provide a reference about the mechanical outputs obtained in the ve...

Purpose: Sprint kinematics have been linked to hamstring injury and performance. This study aimed to examine if a specific 6-week multimodal intervention, combining lumbopelvic control and unning technique exercises, induced changes in pelvis and lower-limb kinematics at maximal speed and improved sprint performance. Methods: Healthy amateur ath...

Two top-level (10"04 and 10"13 in 100-m dash) and 2 sub-elite (10"97 and 11"44 in 100-m dash) male sprinters completed, after a standardised warm-up, various jump, sprint and weightlifting exercises in two consecutive days at the start of pre-season. Before and 30 s after the tests, the [La − ] were measured with a portable lactate analyser. The to...

Citation: Akl, A.-R.; Gonçalves, P.; Fonseca, P.; Hassan, A.; Vilas-Boas, J.P.; Conceição, F. Muscle Co-Activation around the Knee during Different Walking Speeds in Healthy Females. Sensors 2021, 21, 677. https://doi. Abstract: The purpose of this study was to examine the changes in co-activation around the knee joint during different walking spee...

This study aimed to assess the association of the mechanical variables derived from the force-velocity (FV) profile (i.e. theoretical maximal force [F0], velocity [V0] and maximal power output [P max ]) with change of direction (COD) performance in soccer, basketball and tennis players. Fifty-four male athletes (soccer n = 23; tennis n = 16; basket...

Background The differences and relationship between joint stiffness and leg stiffness can be used to characterize the lower limb behavior during different walking speeds. Research question This study aimed to investigate the differences in whole leg and lower limb joint stiffness at different walking speeds and the interactions between leg and low...

The paddling stroke rate (SR) is one of the key determinants of flat water kayak performance. The aim of this study was to analyse the way in which the kayak paddler changes the duration of the water and aerial phases due to the increase in stroke rate. Ten elite kayak paddlers (five males and five females) were analysed performing 200 m on-water t...

Palavras-Chave: Modelo, Músculo, Potenciação, Força velocidade. Resumo. O objectivo do presente trabalho foi desenvolver um modelo múscular do tipo Hill, que considera os efeitos da activação e elasticidade muscular na produção da força. Para este propósito foram desenvolvidas diferentes equações para as relações força-comprimento, força-velocidade...

This study aimed to observe the effect of 8 weeks of resisted sled training (RST), with optimal loading for maximal power output production and initial levels of force, on the magnitude of improvement in sprint performance and individual sprint mechanical outputs in female amateur rugby union players. The study examined the horizontal Power-Force-V...

Jumping ability has been identified as one of the best predictors of dance performance. The latest findings in strength and conditioning research suggest that the relationship between force and velocity mechanical capabilities, known as the force-velocity profile, is a relevant parameter for the assessment of jumping ability. In addition, previous...

Background: Medicine and Physical Education can work together to solve many h ealth problems. Bodybuilding is a multidisciplinary area whose goals can range from body development to the correction of postural problems and the resolution of various pathologies related to human movement. In the case in analysis, the patient presented (at rest) locali...

Aims The purpose of this study was to compare the effects of hamstring eccentric (NHE) strength training versus sprint training programmed as complements to regular soccer practice, on sprint performance and its mechanical underpinnings, as well as biceps femoris long head (BFlh) architecture. Methods In this prospective interventional control stu...

Purpose: Ballet dancers are required to achieve performance feats such as exciting and dramatic elevations. Dancers with a greater jump height can perform a wider range of skills during their flight time and implement more specific technical skills related to the aesthetic components of a dance choreography. New findings suggest the relationship b...

Background: Patellofemoral Pain Syndrome (PFPS) represents anterior knees' diseases. The PFPS is a multifactorial disease, with high prevalence. It presents a direct relationship of deterioration through the act of squatting, descending and climbing stairs, interfering both in working and daily activities. The main purpose of the study will be to f...

Background: Patellofemoral Pain Syndrome (PFPS) represents anterior knees’ diseases. The PFPS is a multifactorial disease, with high prevalence. It presents a direct relationship of deterioration through the act of squatting, descending and climbing stairs, interfering both in working and daily activities. The main purpose of the study will be to f...

Unstable surfaces (US) are often used to introduce instability into conventional push-up (PU) exercise. The goal of this study was to investigate the effects of an unstable surface (BOSU®), applied into different locations (under the hands or feet), on the muscle activation patterns and ground reaction forces (GRF) production. Twelve healthy male s...

Fatigue decreases performance and physical strength causing incidents and accidents in operational settings. During military operations, soldiers encounter extreme conditions, which combined lead to a fatigue status that can cause serious physiological impairments, decreasing performance on the battlefield. Comprehensive studies in realistically st...

This study is a part of weightlifting "Training-Dietary-Competition" (TDC) cycle ontology. The main objective of TDC-cycle is to build a knowledge framework for Olympic weightlifting, bringing together related fields such as training methodology, weightlifting biomechanics, and nutrition while modelling the synergy among them. In so doing, terminol...

Studies in weightlifting have been characterized by unclear results, and paucity of information. This is due to the fact that enhancing the understanding of the mechanics of successful lift requires collaborative contributions of several stakeholders such as coach, nutritionist, biomechanist, and physiologist as well as the aid of technical advance...

This study aimed to investigate the effect of 8 weeks of plyometric training on jumping, speed and change of direction speed (CoD) abilities of young soccer players. The training was applied twice a week, following a linear periodization model, with progressive increment in training volume [total volume per session: 45 to 88 foot contacts]. Eightee...

Este estudo teve como objetivo investigar o efeito de 8 semanas de treino pliométrico na capacidade de salto, de velocidade e de agilidade de jovens futebolistas. O treino foi aplicado 2 vezes por semana, seguindo um modelo de periodização linear, com aumento progressivo do volume de treino [volume total por sessão: 45 a 88 contactos]. A amostra fo...

The aim of this study was to look at differences in countermovement jump (CMJ) performance and selected kinetic parameters in athletes of different training backgrounds and to examine the relationships between these parameters. The subjects were 14 endurance athletes, 12 sprinters, and 13 fire-fighter aspirants (controls); each performed two CMJ on...

Desenvolvemos um modelo muscular do tipo Hill que incorpora os efeitos da activação, elasticidade e história na produção da força muscular. A sua implementação pressupõe um equilíbrio nos comprimentos e forças desenvolvidas pela unidade músculotendão e os seus elementos constituintes. Conhecendo o comprimento da unidade músculo-tendão resultante do...

Using theoretical principles, the components of drag (friction DF, pressure DPR and wave DW) of a single-seat kayak were analysed. The purpose was to examine the effect of changes in wetted surface area due to changes in kayaker’s weight and the relative contribution of DF, DPR and DW to the total passive drag as function of velocity. The total pas...

The push-up (PU) is one of the most common exercises used in the strength training programs for the upper body. Since it is limited to the body weight, fitness trainers use several exercise types (e.g. unstable surfaces) in order to increase the activity of the involved muscles (Freeman et al., 2006). This study aimed to analyze the changes in musc...

Purpose: 1) to analyze the reliability and validity of a simple computation method to evaluate force (F), velocity (v) and power (P) output during a countermovement jump (CMJ) suitable for use in field conditions; and 2) to verify the validity of this computation method to compute the CMJ Force-velocity (F-v) profile (including unloaded and loaded...

The present article presents a project that studies the decrease of physical and mental performance of soldiers submitted to extreme dry hot conditions and the effectiveness of acclimation procedures to prevent the usual heat illnesses of the subjects in missions. A series of tests in controlled environment at 22°C-40% RH and at 40°C-30% RH was per...

Drag is one of the major factors that influences kayaking performance. To focus on the drag of the kayak's hull shape and the paddlers' weight per se, the passive drag (Dp) was measured on a flat-water sprint course for one paddler with added weights. Dp was measured by an electromechanical towing device using a load cell, at incremental and consta...

The purpose of this study was to investigate the relationship between movement velocity and relative load in three lower limbs exercises commonly used to develop strength: leg press, full squat and half squat. The percentage of one repetition maximum (%1RM) has typically been used as the main parameter to control resistance training; however, more...

In sprint kayaking the role that paddling technique plays in optimising paddle forces and resultant kayak kinematics is still unclear. The aim of this study was to analyse the magnitude and shape of the paddle force-time curve at different stroke rates, and their implications for kayak performance. Ten elite kayak paddlers (five males and five fema...

A simple method for evaluating force (F), velocity (V) and power (P) output during a squat jump (SJ) was validated by Samozino et al. (2008, J Biomech, 41: 2940–5), who also showed the existence of an optimal force-velocity profile during SJ (2012, MSSE, 44(2):313–22). Counter Movement Jump (CMJ) is a very common test in sports training and testing...

Purpose To study the effect of a countermovement on the lower limb force–velocity (F–v) mechanical profile and to experimentally test the influence of F–v mechanical profile on countermovement jump (CMJ) performance, independently from the effect of maximal power output (P max). Methods Fifty-four high-level sprinters and jumpers performed vertical...

This study aimed to determine whether subject-specific individual muscle models for the ankle plantar flexors could be obtained from single joint isometric and isovelocity maximum torque measurements in combination with a model of plantar flexion. Maximum plantar flexion torque measurements were taken on one subject at six knee angles spanning full...

This study aimed to determine whether subject-specific individual muscle models for the ankle plantarflexors could be obtained from single joint isometric and isovelocity maximum torque measurements in combination with a model of plantarflexion. Maximum plantarflexion torque measurements were taken on one subject at six knee angles spanning full fl...

This study determines whether maximal voluntary ankle plantar flexor torque could be more accurately represented using a torque generator that is a function of both knee and ankle kinematics. Isovelocity and isometric ankle plantar flexor torques were measured on a single participant for knee joint angles of 111° to 169° (approximately full extensi...

2 The aim of this study was to measure and compare the leg kinematics and kinetics, while executing half-squat with a large spectrum of loads and three different track-and-field throwing actions (hammer, discus and javelin throws). One experienced thrower of each discipline was selected. Knee angular velocity, knee angle and vertical ground reactio...

4 LABIOMEP, Faculty of Sports Univ. Porto, Portugal 5 The main purpose of this work was to perform a dynamometric analysis of the step in resisted sprint with sled towing, using different connection points (vest and belt) as well as distinct velocities (90% and 92,5% of the maximum speed). INTRODUCTION: The athlete performance during sprinting race...

3 The purpose of this study was to investigate different power (P) parameters in Squat (S) and Leg press (LP) exercises, considering joint angle. Male trained subjects (n=8) were submitted to a load progression for S and LP over two sessions, separated by more than 96h in a randomized manner. The force, knee amplitude, and velocities were collected...

2 The aim of this study is to verify if the Portuguese athletes of Pole Vaulting make use of visual control strategies to regulate the approach run. A Doppler speedometer was used to collected data in the Torneio "Rio Largo Cidade de Espinho" and in the Portuguese Indoor Athletics Championship. It was concluded that athletes from our sample did not...

A setup for assessing the performance obtained in horizontal jumps has been described. One of the main challenges is to provide meaningful and timely information to elite athletes. This assessment program started in 2007 with some of the best jumpers and combines kinematic and dynamic information. Results obtained allowed to identify the weaknesses...

INTRODUCTION: The take-off plays an important role on the high jump (HJ) performance, since it is there where the trajectory of the centre of mass is defined (Tellez, 1993) in order to achieve the maximum possible height and clear the bar (Dapena, 1988). The literature has presented several studies using kinematic parameters, however there are very...

Exercise seems to attenuate the postural control system and anticipatory postural adjustments (APAs) decline, but no conclusive findings are available. This study analyzes, in elderly people, the exercise effect in APAs during the raising of a load with both arms in the sagittal plane. Twenty eight males over the age of 60 (65.8 +/- 4.07 yr old)-9...

RESuMO: Á análise do movimento do swing em Golfe está profusamente ilustrada em livros e vídeos, mas ao inverso de outras modalidades desportivas, pouco estudada no âmbito da biomecânica e debatida em publicações cientjflcas. O objectivo deste estudo foi investigar a influência do padrão cinemático no swing de três tacos d~ferentes, o drive (D), o...

The purpose of this research was to characterise and compare two variants of the track- start technique for ventral swimming races, using simultaneous and synchronised dynamic and kinematic data. Results indicated that the track-start variant with rear projection of the centre of gravity (TSR) is able to produce higher impulses and velocities, but...