Kinematic, kinetic and EMG analysis of four front crawl flip turn techniques

Abstract

This study aimed to analyse the kinematic, kinetic and electromyographic characteristics of four front crawl flip turn technique variants. The variants distinguished from each other by differences in body position (i.e., dorsal, lateral, ventral) during rolling, wall support, pushing and gliding phases. Seventeen highly trained swimmers (17.9 ± 3.2 years old) participated in interventional sessions and performed three trials of each variant, being monitored with a 3-D video system, a force platform and an electromyography (EMG) system. Studied variables: rolling time and distance, wall support time, push-off time, peak force and horizontal impulse at wall support and push-off, centre of mass horizontal velocity at the end of the push-off, gliding time, centre of mass depth, distance, average and final velocity during gliding, total turn time and electrical activity of Gastrocnemius Medialis, Tibialis Anterior, Biceps Femoris and Vastus Lateralis muscles. Depending on the variant, total turn time ranged from 2.37 ± 0.32 to 2.43 ± 0.33 s, push-off force from 1.86 ± 0.33 to 1.92 ± 0.26 BW and centre of mass velocity during gliding from 1.78 ± 0.21 to 1.94 ± 0.22 m · s(-1). The variants were not distinguishable in terms of kinematical, kinetic and EMG parameters during the rolling, wall support, pushing and gliding phases.

Start and turn performances of elite sprinters at the 2016 European Championships in swimming

“…Overall, researchers had a strong interest on the swim stroke, disregarding the acyclic phases of the race (i.e., the start and the turn). Albeit, studies can be found about such topic (e.g., Pereira et al, 2015;Vantorre, Seifert, Fernandes, Vilas-Boas, & Chollet, 2010;Veiga, Roig, & Gómez-Ruano, 2016). However, there is no evidence about how elite swimmers behave in major competitions in all four strokes.…”

“…Moreover, it was reported that the start performance should rely on the optimisation of the underwater phase (i.e., gliding, dolphin kicks and water breakout) before starting the swim stroke (e.g., Guimarães & Hay, 1985). The body of knowledge on turning is also rather scarce, when comparing to the swim stroke (e.g., Pereira et al, 2015;Slawson, Conway, Jusham, Le Sage, & West, 2010;. A study conducted by Mason and Cossor (2001) concluded that the fastest swimmers were not the fastest turners.…”

3D Device for Forces in Swimming Starts and Turns

“…Two start block projects were previously designed: (i) a bulky and solid structure and (ii) a lattice block with a declination support, which was replaced by a lattice galvanized steel structure with zero inclination due to excessive mass and reduced stability showed by the previous structures. The starting block was projected to be fixed over an underwater structure attached vertically to the swimming pool wall by front and rear edges, being similar to a previous structure used by Pereira et al [13,14] and de Jesus et al [24] for flip turn and backstroke start kinetics assessment. The first underwater structure included a two independent force plates support.…”

“…The description of forces generated during swimming turns also started in the 1970s using uniaxial force plates to assess the horizontal component in tumble and open turns (e.g., [11]). Swimming turns external forces analysis using three-dimensional force plates is still scarce, with the flip technique and its variants being the most commonly investigated (e.g., [12,13]). A double underwater tri-axial force plate solution developed for independent assessment of forces applied by each foot in a backstroke start can also provide a direct measurement of the combined forces exerted during turns and the determination of foot position.…”

“…A double underwater tri-axial force plate solution developed for independent assessment of forces applied by each foot in a backstroke start can also provide a direct measurement of the combined forces exerted during turns and the determination of foot position. Furthermore, in some turn techniques, coaches can assess laterality data if the foot location is compatible with each force platform (e.g., [13]). Mason and co-authors' underwater force platform design has a multitude of holes system to reduce wave effects [2].…”