Effect of three different set-up conditions on the propulsive force measures, reliability, and ecological validity during front crawl tethered-swimming

2021 ◽  
pp. 1-20
Author(s):  
Otávio Joaquim Baratto de Azevedo ◽  
Clara Knierim Correia ◽  
Gustavo Soares Pereira ◽  
Luciano Sales Prado ◽  
Helio Roesler ◽  
...  
Keyword(s):  
Ecological Validity ◽  
Propulsive Force ◽  
Front Crawl ◽  
Set Up

Coordination changes in front-crawl swimming

2020 ◽  
Vol 476 (2237) ◽  
pp. 20200071
Author(s):  
R. Carmigniani ◽  
L. Seifert ◽  
D. Chollet ◽  
C. Clanet
Keyword(s):  
Physical Model ◽  
Critical Velocity ◽  
Recovery Time ◽  
Large Range ◽  
Open Water ◽  
Propulsive Force ◽  
Relative Duration ◽  
Front Crawl ◽  
Stroke Cycle

We report the evolution of the coordination with velocity in front-crawl swimming which is used in competitions over a large range of distances (from 50 m up to 25 km in open-water races). Inside this single stroke, top-level swimmers show different patterns of arm organization. At low velocities, swimmers select an alternated stroke with gliding pauses during their propulsion. The relative duration of the gliding pauses on a stroke cycle is independent of the velocity in this first regime. Above a critical velocity, the relative duration of the gliding pauses starts to decrease as speed increases. Above a second critical velocity, the gliding pauses disappear and the swimmers start to superpose their propulsion phases. These three regimes are first revealed experimentally and then studied theoretically. It appears that below the first critical velocity, swimmers use a constant coordination index and vary their speed by varying their propulsive force to minimize their cost of propulsion. For larger velocities, swimmers use their maximum propulsive force and vary their recovery time to increase further their speed. The physical model developed is general and could be applied to understand other modes of locomotion.

scholarly journals Is There Any Effect of Symmetry on Velocity of the Four Swimming Strokes?

Symmetry ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 12
Author(s):  
Raul Filipe Bartolomeu ◽  
Pedro Rodrigues ◽  
Catarina Costa Santos ◽  
Mário Jorge Costa ◽  
Tiago Manuel Barbosa
Keyword(s):  
Force Production ◽  
Swimming Velocity ◽  
Propulsive Force ◽  
Front Crawl ◽  
Pressure System ◽  
Contralateral Limb ◽  
The Mean ◽  
Limb Asymmetry ◽  
Different Characteristics ◽  
Full Body

The different characteristics of the four swimming strokes affect the interplay between the four limbs, acting as a constraint to the force produced by each hand and foot. The purpose of this study was to analyze the symmetry of force production with a varying number of limbs in action and see its effect on velocity. Fifteen male swimmers performed four all-out bouts of 25-m swims in the four strokes in full-body stroke and segmental actions. A differential pressure system was used to measure the hands/feet propulsive force and a mechanical velocity meter was used to measure swimming velocity. Symmetry index was calculated based on the force values. All strokes and conditions presented contralateral limb asymmetries (ranging from 6.73% to 28% for the peak force and from 9.3% to 35.7% for the mean force). Backstroke was the most asymmetric stroke, followed-up by butterfly, front crawl, and breaststroke. Kicking conditions elicited the higher asymmetries compared with arm-pull conditions. No significant associations were found between asymmetries and velocity. The absence of such association suggests that, to a certain and unknown extent, swimming may benefit from contralateral limb asymmetry.

scholarly journals The cognitive mechanisms of adversarial humor

2006 ◽  
Vol 19 (3) ◽  
Author(s):  
Tony Veale ◽  
Kurt Feyaerts ◽  
Geert Brône
Keyword(s):  
Cognitive Linguistics ◽  
Ecological Validity ◽  
Language Game ◽  
Cognitive Mechanisms ◽  
Basic Principles ◽  
Multi Agent ◽  
Pragmatic Account ◽  
Set Up ◽  
Conceptual Meaning ◽  
Different Levels

AbstractIn this paper, we provide an in-depth cognitive analysis of a specific humor strategy we coin “trumping”, a multi-agent language game that revolves around the subversion of the linguistic forms of exchange. In particular, we illustrate how, in a conversational setting, agents can “reflect” and “distort” the linguistic-conceptual construal of each others' utterances. Because this reflection or parallelism in the trumping game can be situated on different levels of linguistic organization, a multi-dimensional semantic-pragmatic account is proposed. Using insights from cognitive linguistics, we show that adversarial agents exploit the conceptual mechanisms underlying the opponent's utterances in order to turn the tables in the humor game. In doing so, an agent can trump an adversary by demonstrating a “hyper-understanding” of the lexico-conceptual meaning of an opponent's utterance. This subversion of construal operations like metaphor, metonymy and salience leads to a sudden manipulation of the discourse space that has been set up in the previous utterance(s) (Langacker 2001). In general, by providing an analysis in terms of basic principles of semantic construal, we argue that a cognitive linguistic treatment of humor has an ecological validity that is lacking in most linguistic humor research.

scholarly journals The Difference of Propulsive Force between Water Surface and Underwater Conditions in Flutter Kick Swimming

Proceedings ◽  
2020 ◽  
Vol 49 (1) ◽  
pp. 167
Author(s):  
Hiroshi Ichikawa ◽  
Hirofumi Shimojo ◽  
Yasuhiro Baba ◽  
Takao Mise ◽  
Rio Nara ◽  
...  
Keyword(s):  
Water Surface ◽  
Surface Condition ◽  
Swimming Pool ◽  
Swimming Velocity ◽  
Propulsive Force ◽  
Drag Forces ◽  
Maximum Effort ◽  
The Difference ◽  
Set Up ◽  
Swimming Technique

This study investigates differences in propulsive force between the water surface and underwater conditions in the flutter kick swimming technique. The subjects were well-trained university male swimmers. A towing device was set up in a 25 m swimming pool to measure the towing force and velocity of the swimmer under two conditions: the swimmer was near the water surface and at a depth of 0.60 m. The swimmers performed the gliding trials and the kicking trials with maximum effort with five towing velocities from 1.2 to 2.4 m/s. The passive drag and the resultant force of the propulsive and drag forces in kick swimming were formulated, respectively. The propulsive force was calculated from the difference between the two formulas. A difference of the propulsive force under conditions in high swimming velocity was observed. This suggests that the water surface condition has advantages of raising the foot above water.

scholarly journals Estimate of propulsive force in front crawl swimming in young athletes

2012 ◽  
pp. 115
Author(s):  
Adalberto Veronese da Costa ◽  
Marcos André dos Santos ◽  
Barbosa Junior ◽  
Manoel da Cunha Costa ◽  
Wilson Viana de Castro Melo
Keyword(s):  
Propulsive Force ◽  
Young Athletes ◽  
Front Crawl

scholarly journals Exploring the Brain Activity Related to Missing Penalty Kicks: An fNIRS Study

2021 ◽  
Vol 3 ◽  
Author(s):  
Max W. J. Slutter ◽  
Nattapong Thammasan ◽  
Mannes Poel
Keyword(s):  
Near Infrared ◽  
Brain Activity ◽  
Ecological Validity ◽  
Temporal Cortex ◽  
Lateral Asymmetry ◽  
Functional Near Infrared Spectroscopy ◽  
Professional Soccer ◽  
And Performance ◽  
Set Up ◽  
The Brain

At vital moments in professional soccer matches, penalties were often missed. Psychological factors, such as anxiety and pressure, are among the critical causes of the mistakes, commonly known as choking under pressure. Nevertheless, the factors have not been fully explored. In this study, we used functional near-infrared spectroscopy (fNIRS) to investigate the influence of the brain on this process. An in-situ study was set-up (N = 22), in which each participant took 15 penalties under three different pressure conditions: without a goalkeeper, with an amiable goalkeeper, and with a competitive goalkeeper. Both experienced and inexperienced soccer players were recruited, and the brain activation was compared across groups. Besides, fNIRS activation was compared between sessions that participants felt anxious against sessions without anxiety report, and between penalty-scoring and -missing sessions. The results show that the task-relevant brain region, the motor cortex, was more activated when players were not experiencing performance anxiety. The activation of task-irrelevant areas was shown to be related to players experiencing anxiety and missing penalties, especially the prefrontal cortex (PFC). More particularly, an overall higher activation of the PFC and an increase of PFC lateral asymmetry were related to anxious players and missed penalties, which can be caused by players' worries about the consequences of scoring or missing the penalty kicks. When experienced players were feeling anxious, their left temporal cortex activation increased, which could be an indication that experienced overthink the situation and neglect their automated skills. Besides, the left temporal cortex activation is higher when inexperienced players succeeded to score a penalty. Overall, the results of this study are in line with the neural efficiency theory and demonstrate the feasibility and ecological validity to detect neurological clues relevant to anxiety and performance from fNIRS recordings in the field.

A Virtual Reality set-up for the combined assessment of behavioral and psychophysiological cue-reactivity in gambling disorder

2020 ◽  
Author(s):  
Luca R. Bruder ◽  
Lisa Scharer ◽  
Jan Peters
Keyword(s):  
Virtual Reality ◽  
Gambling Disorder ◽  
Electrodermal Activity ◽  
Ecological Validity ◽  
Cue Reactivity ◽  
Critical Role ◽  
Temporal Discounting ◽  
Sports Betting ◽  
Model Parameters ◽  
Set Up

AbstractIncreased reactivity to addiction related cues (cue-reactivity) plays a critical role in the maintenance of addiction. Studies assessing cue-reactivity in gambling disorder often suffer from low ecological validity due to the usage of picture stimuli in a neutral lab environment. Here we describe a novel virtual reality (VR) set-up for the concurrent assessment of behavioral and psychophysiological cue-reactivity in gambling disorder. On two days, thirty-four healthy non-gambling participants explored two rich and navigable VR-environments (neutral: cafe vs. gambling-related: casino and sports-betting facility), while their electrodermal activity was measured using remote sensors. In addition, participants completed a temporal discounting task implemented in each VR environment. On a third day, participants performed the task in a standard lab testing context. We then used comprehensive computational modeling using both standard softmax and drift diffusion model (DDM) choice rules to assess the reliability of discounting model parameters assessed in VR. Test-retest reliability estimates were good to excellent for the discount rate log(k), whereas they were poor to moderate for additional DDM parameters. Differences in model parameters between standard lab testing and VR, reflecting reactivity to the different environments, were mostly numerically small and of inconclusive directionality. Finally, while exposure to VR generally increased tonic skin conductance, this effect was not modulated by the neutral vs. gambling-related VR-environment. Taken together this proof-of-concept study in non-gambling participants demonstrates the feasibility assessing both physiological and behavioral cue-reactivity in VR. We show that temporal discounting measures obtained in VR are reliable, suggesting that VR is a promising tool for an ecologically valid assessment of cue-reactivity in gambling disorder.

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