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Ballistic stretching

Mohamed Frikha, Mohammad S Derbel, Nesrine Chaâri, Adnene Gharbi, Karim Chamari
The aim of the study was to compare the effect of stretching procedures on global coordination and accuracy in instep soccer kicks achieved in different stress conditions. Twenty male young soccer players completed the global coordination test (GC), the instep kicking accuracy test in free (FKA) and in time-pressure (TPKA) conditions, either after static (SS), dynamic (DS), ballistic (BS) or no-stretching (CTR) protocols, on nonconsecutive days and in a randomized order. After performing a 5min standardized intensity jogging (70% of MAV), followed by stretching exercises for 10min, each participant completed, successively, the GC, FKA and TPKA tests...
April 7, 2017: Human Movement Science
Srinivasan S Naarayan, Ghatu Subhash
Wave propagation characteristics in long cylindrical specimens of ballistic gelatine have been investigated using a high speed digital camera and hyper elastic constitutive models. The induced transient deformation is modelled with strain rate dependent Mooney-Rivlin parameters which are determined by modelling the stress-strain response of gelatine at a range of strain rates. The varying velocity of wave propagation through the gelatine cylinder is derived as a function of prestress or stretch in the gelatine specimen...
January 23, 2017: Journal of the Mechanical Behavior of Biomedical Materials
Camila D Lima, Lee E Brown, Megan A Wong, Whitney D Leyva, Ronei S Pinto, Eduardo L Cadore, Cassio V Ruas
Lima, CD, Brown, LE, Wong, MA, Leyva, WD, Pinto, RS, Cadore, EL, and Ruas, CV. Acute effects of static vs. ballistic stretching on strength and muscular fatigue between ballet dancers and resistance-trained women. J Strength Cond Res 30(11): 3220-3227, 2016-Stretching is used to increase joint range of motion, but the acute effects can decrease muscle strength. However, this may depend on the population or mode of stretching. The purpose of this study was to compare the acute effects of static vs. ballistic stretching on strength and muscular fatigue between ballet dancers and resistance-trained women...
November 2016: Journal of Strength and Conditioning Research
Utku Alemdaroglu, Yusuf Köklü, Mitat Koz
BACKGROUND: The purpose of this study was to compare the acute effects of different stretching types on sprint performance in taekwondo practitioners. METHODS: Twelve male taekwondo practitioners performed stretching exercises using different types (ballistic, proprioceptive neuromuscular facilitation (PNF), static stretching) in a random order at three-day intervals; there was also a control condition involving no stretching exercises. The subjects performed 2 maximal 20m sprints (with 10m split times also recorded) with a recovery period of 1 minute immediately post stretching and at 5, 10, 15 and 20 minutes after stretching...
July 21, 2016: Journal of Sports Medicine and Physical Fitness
Mohamed Frikha, Nesrine Chaâri, Mohammad S Derbel, Yousri Elghoul, Anatoly V Zinkovsky, Karim Chamari
BACKGROUND: The present study addressed the lack of data on the effect of different types of stretching on selected measures of throwing accuracy. We hypothesized that the stretching procedures, within pre-exercise warm-up, could affect the accuracy and the consistency in throwing darts performances under different stress conditions. METHODS: Eighteen right-handed schoolboys (13.1± 0.4 years, 166 ± 0.1 cm and 54.5 ± 9kg; mean ± SD) completed the darts throwing accuracy test in free (FDT) and in time-pressure (TPDT) conditions, either after static (SS), dynamic (DS), ballistic (BS) or no-stretching (NS) protocols, on nonconsecutive days and in a counter-balanced randomized order...
July 7, 2016: Journal of Sports Medicine and Physical Fitness
A Konrad, S Stafilidis, M Tilp
The purpose of this study was to investigate the influence of a single static, ballistic, or proprioceptive neuromuscular facilitation (PNF) stretching exercise on the various muscle-tendon parameters of the lower leg and to detect possible differences in the effects between the methods. Volunteers (n = 122) were randomly divided into static, ballistic, and PNF stretching groups and a control group. Before and after the 4 × 30 s stretching intervention, we determined the maximum dorsiflexion range of motion (RoM) with the corresponding fascicle length and pennation angle of the gastrocnemius medialis...
July 1, 2016: Scandinavian Journal of Medicine & Science in Sports
Camila D Lima, Lee E Brown, Ronei S Pinto, Cassio V Ruas, Megan A Wong, Whitney D Leyva
No abstract text is available yet for this article.
May 2016: Medicine and Science in Sports and Exercise
Gavin Williams, Louise Ada, Leanne Hassett, Meg E Morris, Ross Clark, Adam L Bryant, John Olver
INTRODUCTION: Traumatic brain injury is the leading cause of disability in young adults aged 15 to 45 years. Mobility limitations are prevalent, and range in severity from interfering with basic day-to-day tasks to restricting participation in higher level social, leisure, employment and sporting activities. Despite the prevalence and severity of physical impairments, such as poor balance and spasticity, the main contributor to mobility limitations following traumatic brain injury is low muscle power generation...
July 2016: Journal of Physiotherapy
Christopher V Anderson
Stretching elastic tissues and using their recoil to power movement allows organisms to release energy more rapidly than by muscle contraction directly, thus amplifying power output. Chameleons employ such a mechanism to ballistically project their tongue up to two body lengths, achieving power outputs nearly three times greater than those possible via muscle contraction. Additionally, small organisms tend to be capable of greater performance than larger species performing similar movements. To test the hypothesis that small chameleon species outperform larger species during ballistic tongue projection, performance was examined during feeding among 20 chameleon species in nine genera...
January 4, 2016: Scientific Reports
Natalia I Rubtsova, Layla N Qasim, Arkady A Kurnosov, Alexander L Burin, Igor V Rubtsov
The development of nanocomposite materials with desired heat management properties, including nanowires, layered semiconductor structures, and self-assembled monolayer (SAM) junctions, attracts broad interest. Such materials often involve polymeric/oligomeric components and can feature high or low thermal conductivity, depending on their design. For example, in SAM junctions made of alkane chains sandwiched between metal layers, the thermal conductivity can be very low, whereas the fibers of ordered polyethylene chains feature high thermal conductivity, exceeding that of many pure metals...
September 15, 2015: Accounts of Chemical Research
H Conrad, F Lehmkühler, B Fischer, F Westermeier, M A Schroer, Y Chushkin, C Gutt, M Sprung, G Grübel
We report x-ray photon correlation spectroscopy experiments on the dynamics of the glass-former polypropylene glycol covering a temperature range from room temperature to the glass transition at T(g)=205 K using silica tracer particles. Three temperature regimes are identified: At high temperatures, Brownian motion of the tracer particles is observed. Near T(g), the dynamics is hyperdiffusive and ballistic. Around 1.12T(g), we observe an intermediate regime. Here the stretching exponent of the Kohlrausch-Williams-Watts function becomes q dependent...
April 2015: Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
Marcos A Sá, Gabriel R Neto, Pablo B Costa, Thiago M Gomes, Cláudio M Bentes, Amanda F Brown, Jefferson S Novaes
This study aimed to investigate the acute effects of passive static and ballistic stretching on maximal repetition performance during a resistance training session (RTS). Nine male subjects underwent three experimental conditions: ballistic stretching (BS); passive static stretching (PSS); and a specific warm-up (SW). The RTS was composed of three sets of 12RM for the following exercises: leg press 45 (LP), leg extension (LE), leg curl (LC), and plantar flexors (PF). Performance of six sessions was assessed 48 hours apart...
March 29, 2015: Journal of Human Kinetics
Yuankai Yue, Layla N Qasim, Arkady A Kurnosov, Natalia I Rubtsova, Robert T Mackin, Hong Zhang, Boyu Zhang, Xiao Zhou, Janarthanan Jayawickramarajah, Alexander L Burin, Igor V Rubtsov
Intramolecular transport of vibrational energy in two series of oligomers featuring alkane chains of various length was studied by relaxation-assisted two-dimensional infrared spectroscopy. The transport was initiated by exciting various end-group modes (tags) such as different modes of the azido (ν(N≡N) and ν(N═N)), carboxylic acid (ν(C═O)), and succinimide ester (νas(C═O)) with short mid-IR laser pulses. It is shown that the transport via alkane chains is ballistic and the transport speed is dependent on the type of the tag mode that initiates the transport...
May 28, 2015: Journal of Physical Chemistry. B
Jae-Hwang Lee, Phillip E Loya, Jun Lou, Edwin L Thomas
Multilayer graphene is an exceptional anisotropic material due to its layered structure composed of two-dimensional carbon lattices. Although the intrinsic mechanical properties of graphene have been investigated at quasi-static conditions, its behavior under extreme dynamic conditions has not yet been studied. We report the high-strain-rate behavior of multilayer graphene over a range of thicknesses from 10 to 100 nanometers by using miniaturized ballistic tests. Tensile stretching of the membrane into a cone shape is followed by initiation of radial cracks that approximately follow crystallographic directions and extend outward well beyond the impact area...
November 28, 2014: Science
Yasumasa Eguchi, Manabu Jinde, Kazuki Murooka, Yoshimasa Konno, Masanori Ohta, Hiroshi Yamato
PURPOSE: Effective recovery from muscle fatigue, especially during rest intervals between periods of high-intensity activity, is important to ensure optimal subsequent performance. Stretching and icing are two types of treatment used for muscle recovery in such situations. However, their effectiveness remains unclear because of a lack of adequate evidence and/or discrepant results of previous studies. We performed a study to elucidate the effects of stretching and icing on muscle fatigue in subjects performing alternating muscle contraction and rest...
December 2014: European Journal of Applied Physiology
F D A Aarão Reis, Dung di Caprio
Random walks (RW) of particles adsorbed in the internal walls of porous deposits produced by ballistic-type growth models are studied. The particles start at the external surface of the deposits and enter their pores in order to simulate an external flux of a species towards a porous solid. For short times, the walker concentration decays as a stretched exponential of the depth z, but a crossover to long-time normal diffusion is observed in most samples. The anomalous concentration profile remains at long times in very porous solids if the walker steps are restricted to nearest neighbors and is accompanied with subdiffusion features...
June 2014: Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
Andreas Konrad, Markus Tilp
The purpose of this study was to investigate the influence of a 6-wk ballistic stretching training program on various parameters of the human gastrocnemius medialis muscle and the Achilles tendon. It is known that ballistic stretching is an appropriate means of increasing the range of motion (RoM), but information in the literature about the mechanical adaptation of the muscle-tendon unit (MTU) is scarce. Therefore, in this study, a total of 48 volunteers were randomly assigned into ballistic stretching and control groups...
July 1, 2014: Journal of Applied Physiology
Berkiye Kirmizigil, Bahtiyar Ozcaldiran, Muzaffer Colakoglu
The aim of this study was to evaluate 3 different flexibility techniques: (a) ballistic stretching (BS), (b) proprioceptive neuromuscular facilitation stretching (PNF) + BS, and (c) PNF + static stretching (SS) on vertical jump (VJ) performance and to determine the most appropriate stretching method during warm-up period before explosive force disciplines. One hundred voluntary male athletes participated in this study. All subjects performed aerobic warm-up (5-minute jog) followed by BS (5 seconds for each stretching exercise), PNF + BS (PNF performed followed by 5 seconds of BS), and PNF + SS (PNF performed followed by 30 seconds of SS) treatment protocol, respectively in the same day...
May 2014: Journal of Strength and Conditioning Research
Natalia I Rubtsova, Arkady A Kurnosov, Alexander L Burin, Igor V Rubtsov
Temperature dependence of intramolecular energy transport in perfluoroalkane oligomers with a chain length of 3-11 carbon atoms terminated by a carboxylic acid moiety on one end and a -CF2H group on another end was studied in solution experimentally and theoretically. Experiments were performed using a dual-frequency relaxation-assisted two-dimensional infrared spectroscopy method. The energy transport was initiated by exciting the C═O stretching mode of the acid and recorded by measuring a cross-peak amplitude between the C═O stretching and the C-H bending modes as a function of the waiting time between the excitation and probing...
July 17, 2014: Journal of Physical Chemistry. B
Andrew T Sensenig, Sean P Kelly, Kimberly A Lorentz, Brittany Lesher, Todd A Blackledge
Spiders in the Orbiculariae spin orb webs that dissipate the mechanical energy of their flying prey, bringing the insects to rest and retaining them long enough for the spider to attack and subdue their meals. Small prey are easily stopped by webs but provide little energetic gain. While larger prey offer substantial nourishment, they are also challenging to capture and can damage the web if they escape. We therefore hypothesized that spider orb webs exhibit properties that improve their probability of stopping larger insects while minimizing damage when the mechanical energy of those prey exceeds the web's capacity...
September 15, 2013: Journal of Experimental Biology
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