Interdisciplinary Center for the Study of Human Performance

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Learning to cycle: a constraint-led intervention programme using different cycling task constraints

Publication . Mercê, Cristiana; Davids, Keith; Catela, David; Branco, Marco; Correia, Vanda; Cordovil, Rita

BackgroundCycling is a foundational movement skill which represents an important motor milestone to achieve in children's lives. The use of a bicycle with training wheels is the most common approach for learning how to cycle, although some evidence suggests that this approach is counterproductive.PurposeUnderpinned by an ecological dynamics and Constraints-led approach, this study investigated whether learning how to ride a conventional bicycle in childhood can be shaped by the specific task constraints related to the kind of training bicycle used beforehand (i.e. balance bike or bicycle with training wheels). This comparison could guide pedagogical practice to facilitate children's learning in cycling and their independent riding.MethodsThe Learning to Cycle intervention programme was introduced to 25 children (M = 6.08 +/- 1.19 years) who could not previously cycle, divided into two treatment groups. One group trained with a bicycle with training wheels (BTW) and another with a balance bicycle (BB) for six sessions, followed by four sessions with a conventional bicycle (CB). The acquisition of independent cycling was assessed, based on established cycle learning milestone achievements, without help: (i) self-launch, (ii) riding for at least 10 (consecutive) metres, and (iii) braking. To be considered an independent rider, participants needed to achieve all these milestones, without any external help. During the CB sessions, the number of sessions that each child needed to acquire each learning milestone and independent cycling were recorded.ResultsThe programme led to a success rate of 88% for achievement of independent cycling on a conventional bicycle, differentiated by 100% success in the BB group and 75% in the BTW group. The BB participants were significantly faster in learning to self-launch, ride, brake, and cycle independently, compared to BTW participants.ConclusionsThe Learning to Cycle programme was effective for facilitating learning in children from three years of age onwards. Using the BB instead of the BTW seems to lead to a more effective and efficient acquisition of independent cycling at earlier ages.

2023-03Journal article

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Perceived self-efficacy by Under-10 tennis players when scaling the equipment and play area

Publication . Gimenez-Egido, Jose Maria; Carvalho, João; Araújo, Duarte; Ortega-Toro, Enrique

The modification of child-sports aims to develop an optimal learning environment that facilitates the emergence of desirable psychological outcomes (e.g., self-efficacy). The aim of the study was to assess the effect of reducing net height and court size on self-efficacy and shot-efficacy of U-10 tennis players in a real-game context. Twenty U-10 tennis players (M = 9.46, SD = 0.66 years of age; M = 3.65, SD = 1.53 years of tennis experience) played two round-robin tournaments one week apart in the same order and schedule. The first tournament was played under the International Tennis Federation's Tennis 10s regulation at green stage (GT). Afterwards, the modified tournament (MT) was played with the same regulation GT, however, net height (0.91 m-0.80 m) and court size (23.77 m x 8.23 m-18.00 m x 8.23 m) were reduced. Results accomplished using Bayesian and Frequentist inferences showed an increase in players' self-efficacy when serving in MT than GT (BF10 = 4.796; delta =-0.576; and p = .011). This is increase may be due to a reduction in their serving faults in MT (BF10 = 6.169; delta =-0.591; and p = .010). Therefore, reducing net height and court size enhances the serve performance and self-efficacy and thus promotes positive tennis experiences.

2023Journal article

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Evaluation of upper limb joint contribution to racket head speed in elite tennis players using IMU sensors: comparison between the cross-court and inside-out attacking Forehand Drive

Publication . Pedro, Bruno; João, Filipa; Lara, Jerusa P. R.; Cabral, Silvia; Carvalho, João; Veloso, António P.

This study aimed to quantify and compare the upper limb angular kinematics and its contributions to the racket head speed between the cross-court (CC) and inside-out (IO) attacking tennis forehand of elite tennis players in a competitive environment. A new approach was used to study the forehand drive with mini-inertial sensors of motion capture to record the kinematic data. Six strokes in each direction per participant (72 shots in total) were chosen for analysis. Upper limb kinematics were calculated in the Visual 3D platform (Visual 3D Professional V5.01.21, C-motion, Germantown, MD, USA). The method used to calculate the upper limb’s contributions was performed with MATLAB software and used the segment’s (upper arm, forearm and hand) angular velocities and their respective displacement vectors obtained through the inertial sensors. Upper limb kinematics demonstrated a higher shoulder rotation in the IO direction with significant differences at the end of the backswing, which could be a key factor in distinguishing the two directions of the shot. Results also demonstrated that the horizontal flexion of the upper arm (around the shoulder joint) was primarily responsible for the racket velocity in the anteroposterior direction (48.1% CC and 45.2% IO), followed by the extension of the forearm (around the elbow joint) (17.3% CC and 20.9% IO) and the internal rotation of the upper arm (around the shoulder joint) (15.6% CC and 14.2% IO). No significant differences were shown in the contributions of upper limbs to the racket head velocity between the two directions of the shot. Tennis coaches and players should develop a specific training programme to perform higher angular velocities in these specific joint rotations.

2022-02-08Journal article

Open access

Perturbations created from the baseline in tennis: a test of barker’s behaviour setting theory

Publication . Carvalho, Adriano; Carvalho, João; Araújo, Duarte

The purpose of this study was to characterise perturbations created from the baseline in men's tennis following Barker's ecological psychology approach. In selected rallies of expert level tennis matches we identified the shot responsible for this perturbation and characterised it using a sequential approach based on the positioning of the players in the court, the technical actions used by both players, and the displacements that each player forced on the opponent. Results reveal specific patterns of player behaviour and types of displacement in response to the opponent. Moreover, we found significant variability of the technical actions and action zones expressed during the perturbation processes. These results suggest that perturbation behaviours are constrained by the 'behaviour setting', which allows individuality during the search for effective solutions to achieve a specific goal. This test of Barker's behaviour setting theory in sport offers a principled guidance for coaches embed psychology into task design for practice sessions.

2022-08Journal article

Open access

Cardiorespiratory and muscle oxygenation responses to voluntary hypoventilation at low lung volume in upper body repeated sprints

Publication . Rosa, Cristóvão H.; Monteiro, Cristina P.; Barata, Cláudia; Espada, Mário C.; Valamatos, Maria João; Bento, André; da Palma Minhalma, Ricardo José; Reis, Joana Filipa

Purpose To investigate the impact of voluntary hypoventilation at low lung volumes (VHL) during upper body repeated sprints (RS) on performance, metabolic markers and muscle oxygenation in Brazilian Jiu-Jitsu (BJJ) athletes. Methods Eighteen male well-trained athletes performed two randomized RS sessions, one with normal breathing (RSN) and another with VHL (RS-VHL), on an arm cycle ergometer, consisting of two sets of eight all-out 6-s sprints performed every 30 s. Peak (PPO), mean power output (MPO), and RS percentage decrement score were calculated. Arterial oxygen saturation (SpO2), heart rate (HR), gas exchange, and muscle oxygenation of the long head of the triceps brachii were continuously recorded. Blood lactate concentration ([La]) was measured at the end of each set. Bench press throw peak power (BPPP) was recorded before and after the RS protocol. Results Although SpO2 was not diferent between conditions, PPO and MPO were signifcantly lower in RS-VHL. V̇ E, HR, [La], and RER were lower in RS-VHL, and VO2 was higher in RS-VLH than in RSN. Muscle oxygenation was not diferent between conditions nor was its pattern of change across the RS protocol infuenced by condition. [La] was lower in RS-VHL than in RSN after both sets. Conclusion Performance was signifcantly lower in RS-VHL, even though SPO2 was not consistent with hypoxemia. However, the fatigue index was not signifcantly afected by VHL, nor was the neuromuscular upper body power after the RSVHL protocol. Additionally, [La] was lower, and oxygen consumption was higher in RS-VHL, suggesting a higher aerobic contribution in this condition.

2024-08-13Journal article

Open access