| description |
Javelin throw involves a sequence of complex movements where the aim is to transfer momentum gained during approach run from the lower body to the upper body. Eventually the flow of kinetic energy is converted into javelin release velocity. At final foot strike the thrower decelerates this forward momentum, and during front foot contact high ground reaction forces are produced. Thrower’s approach velocity, javelin release speed and position during flight, braking action of the front leg, technical aspects of the throwing arm and posture of the thrower affect the throwing performance. However, the significance of ground reaction forces for the javelin throwing performance is not well-understood. The purpose of the study was to investigate whether ground reaction forces, front leg kinematics and approach velocity are associated with throwing performance in male and female javelin throwers. 11 male (age 24 ± 3 years, height 184 ± 8 cm, body mass 96 ± 12 kg, personal record 76.76 ± 5.43 m) and 13 female (age 25 ± 6 years, height 171 ± 5 cm, body mass 80 ± 11 kg, personal record 55.79 ± 5.85 m) javelin throwers were instructed to perform six maximal javelin throw attempts indoors. Ground reaction forces were measured with force platforms, and horizontal and vertical peak force, impulse and loading rate were analyzed. 3D motion analysis was performed to determine release parameters, kinematic variables and approach velocity. Theoretical throwing distance was calculated based on throwing parameters. For male throwers horizontal normalized peak force was associated with theoretical throwing distance (r = -0.636, p = 0.035), javelin release velocity (r = -0.609, p = 0.047) and pull distance (r = -0.624, p = 0.040). Delivery step length was associated with vertical (r = 0.674, p = 0.023) and horizontal peak force (r = -0.840, p = 0.001) and normalized horizontal peak force (r = -0.818, p = 0.002). For female throwers ground reaction forces did not correlate with throwing performance directly, but release height was associated with vertical (r = 0.721, p = 0.005) and horizontal (r = -0.607, p = 0.028) peak forces. Javelin release speed was associated with delivery step length (r = -0.560, p = 0.046) and ankle height at back foot contact (r = 0.582, p = 0.037). Approach velocity was not associated with throwing performance. For both genders horizontal braking might be more significant for throwing performance compared to vertical direction. Male throwers may need to increase horizontal braking to optimize throwing distance, javelin release velocity and pull distance while regulating vertical impact to control javelin position. Braking action can be emphasized with longer delivery step length and with greater approach velocity the demand for braking action increases. For female, peak forces might explain throwing performance indirectly. Female throwers should be able to produce enough force to support high pelvis posture and release height. Heel-dominant front foot technique might enhance braking action. To reach the optimal javelin release speed, delivery step length should not be overemphasized.
Keihäänheittosuoritus on monivaiheinen liikeketju, jossa heittäjä muuntaa juoksuvauhtinsa nopeuden alavartalosta ylävartalon kautta heittokäteen. Irrotushetkellä nopeus välitetään lopulta keihään lähtönopeudeksi. Tukijalalle törmääminen jarruttaa heittäjän etenemisliikettä, jolloin kontaktin aikana tuotetaan suuria reaktiovoimia. Keihäänheittosuorituskykyyn ja heiton pituuteen vaikuttavat heittäjän nopeus, keihään lähtönopeus ja lentoasento, tukijalan jarrutustyön tehokkuus, heittokäden tekniikka sekä heittäjän asento heittohetkellä. Sen sijaan tuotettujen reaktiovoimien merkitystä heittosuorituskyvylle ei vielä täysin ymmärretä. Pro gradu -tutkielman tarkoituksena oli selvittää, onko reaktiovoimilla, tukijalan kinematiikalla tai heittäjän tulonopeudella yhteyttä heittosuorituskykyyn mies- ja naiskeihäänheittäjillä. Tutkimukseen osallistui 11 mies- (ikä 24 ± 3 v, pituus 184 ± 8 cm, paino 96 ± 12 kg, ennätys 76.76 ± 5.43 m) ja 13 naiskeihäänheittäjää (ikä 25 ± 6 v, pituus 171 ± 5 cm, paino 80 ± 11 kg, ennätys 55.79 ± 5.85 m), jotka heittivät kuusi maksimaalista kilpailusuoritusta mukailevaa heittoa sisätiloissa heittopressuun. Heitoista mitattiin reaktiovoimia voimalevyillä, ja reaktiovoimista analysoitiin vertikaalinen sekä horisontaalinen huippuvoima, impulssi ja voimantuottonopeus. Heittovideoista analysoitiin heittoparametrit, kinemaattiset muuttujat sekä tulonopeus. 3D-liikeanalyysin avulla. Heittoparametrien avulla heitoille laskettiin teoreettinen pituus. Miesheittäjillä horisontaalinen kehonpainoon suhteutettu huippuvoima oli yhteydessä teoreettiseen heittopituuteen (r = -0.636, p = 0.035), keihään lähtönopeuteen (r = -0.609, p = 0.047) sekä vetomatkaan (r = -0.624, p = 0.040). Askelpituuteen olivat yhteydessä absoluuttinen vertikaalinen (r = 0.674, p = 0.023) ja horisontaalinen huippuvoima (r = -0.840, p = 0.001) sekä kehonpainoon suhteutettu horisontaalinen huippuvoima (r = -0.818, p = 0.002). Naisheittäjillä reaktiovoimat eivät suoraan olleet yhteydessä heittosuorituskykyyn, mutta irrotuskorkeuteen olivat yhteydessä vertikaalinen (r = 0.721 p = 0.005) sekä horisontaalinen (r = -0.607, p = 0.028) huippuvoima. Keihään lähtönopeuteen olivat yhteydessä askelpituus (r = -0.560, p = 0.046) sekä ristiaskelhypyn aikainen nilkkakorkeus (r = 0.582, p = 0.037). Tulonopeus ei ollut yhteydessä heittosuorituskykyyn kummallakaan sukupuolella. Sekä mies- että naiskeihäänheittäjille horisontaalisesti suuntautuva jarrutustyö vaikuttaisi olevan vertikaalista törmäämistä merkityksellisempää. Miesheittäjien tulisi korostaa vaakasuuntaista jarrutustyötä heiton pituuden, keihään lähtönopeuden sekä vetopituuden optimoimiseksi sekä mahdollisesti hillitä vertikaalista törmäämistä keihään asennon hallitsemiseksi. Askelpituutta pidentämällä jarrutustyötä voidaan tehostaa, ja tulonopeuden kasvaessa jarrutustyön vaatimus lisääntyy. Naisheittäjillä huippuvoimat saattavat selittää heittosuorituskykyä epäsuorasti, ja heittäjien on kyettävä tuottamaan tarpeeksi voimaa korkean lantion asennon sekä irrotuskorkeuden mahdollistamiseksi. Jarrutustyötä voidaan tehostaa astumalla tukijalan askel kantapäävoittoisesti. Optimaalisen keihään lähtönopeuden saavuttamiseksi tukijalan askelpituutta ei tule ylikorostaa.
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| fullrecord |
[{"key": "dc.contributor.advisor", "value": "Ahtiainen, Juha", "language": null, "element": "contributor", "qualifier": "advisor", "schema": "dc"}, {"key": "dc.contributor.advisor", "value": "K\u00f6ykk\u00e4, Miika", "language": null, "element": "contributor", "qualifier": "advisor", "schema": "dc"}, {"key": "dc.contributor.author", "value": "Reinholm, Gia", "language": "", "element": "contributor", "qualifier": "author", "schema": "dc"}, {"key": "dc.date.accessioned", "value": "2024-05-24T09:48:48Z", "language": null, "element": "date", "qualifier": "accessioned", "schema": "dc"}, {"key": "dc.date.available", "value": "2024-05-24T09:48:48Z", "language": null, "element": "date", "qualifier": "available", "schema": "dc"}, {"key": "dc.date.issued", "value": "2024", "language": null, "element": "date", "qualifier": "issued", "schema": "dc"}, {"key": "dc.identifier.uri", "value": "https://jyx.jyu.fi/handle/123456789/95159", "language": null, "element": "identifier", "qualifier": "uri", "schema": "dc"}, {"key": "dc.description.abstract", "value": "Javelin throw involves a sequence of complex movements where the aim is to transfer momentum gained during approach run from the lower body to the upper body. Eventually the flow of kinetic energy is converted into javelin release velocity. At final foot strike the thrower decelerates this forward momentum, and during front foot contact high ground reaction forces are produced. Thrower\u2019s approach velocity, javelin release speed and position during flight, braking action of the front leg, technical aspects of the throwing arm and posture of the thrower affect the throwing performance. However, the significance of ground reaction forces for the javelin throwing performance is not well-understood. The purpose of the study was to investigate whether ground reaction forces, front leg kinematics and approach velocity are associated with throwing performance in male and female javelin throwers. 11 male (age 24 \u00b1 3 years, height 184 \u00b1 8 cm, body mass 96 \u00b1 12 kg, personal record 76.76 \u00b1 5.43 m) and 13 female (age 25 \u00b1 6 years, height 171 \u00b1 5 cm, body mass 80 \u00b1 11 kg, personal record 55.79 \u00b1 5.85 m) javelin throwers were instructed to perform six maximal javelin throw attempts indoors. Ground reaction forces were measured with force platforms, and horizontal and vertical peak force, impulse and loading rate were analyzed. 3D motion analysis was performed to determine release parameters, kinematic variables and approach velocity. Theoretical throwing distance was calculated based on throwing parameters. For male throwers horizontal normalized peak force was associated with theoretical throwing distance (r = -0.636, p = 0.035), javelin release velocity (r = -0.609, p = 0.047) and pull distance (r = -0.624, p = 0.040). Delivery step length was associated with vertical (r = 0.674, p = 0.023) and horizontal peak force (r = -0.840, p = 0.001) and normalized horizontal peak force (r = -0.818, p = 0.002). For female throwers ground reaction forces did not correlate with throwing performance directly, but release height was associated with vertical (r = 0.721, p = 0.005) and horizontal (r = -0.607, p = 0.028) peak forces. Javelin release speed was associated with delivery step length (r = -0.560, p = 0.046) and ankle height at back foot contact (r = 0.582, p = 0.037). Approach velocity was not associated with throwing performance. For both genders horizontal braking might be more significant for throwing performance compared to vertical direction. Male throwers may need to increase horizontal braking to optimize throwing distance, javelin release velocity and pull distance while regulating vertical impact to control javelin position. Braking action can be emphasized with longer delivery step length and with greater approach velocity the demand for braking action increases. For female, peak forces might explain throwing performance indirectly. Female throwers should be able to produce enough force to support high pelvis posture and release height. Heel-dominant front foot technique might enhance braking action. To reach the optimal javelin release speed, delivery step length should not be overemphasized.", "language": "en", "element": "description", "qualifier": "abstract", "schema": "dc"}, {"key": "dc.description.abstract", "value": "Keih\u00e4\u00e4nheittosuoritus on monivaiheinen liikeketju, jossa heitt\u00e4j\u00e4 muuntaa juoksuvauhtinsa nopeuden alavartalosta yl\u00e4vartalon kautta heittok\u00e4teen. Irrotushetkell\u00e4 nopeus v\u00e4litet\u00e4\u00e4n lopulta keih\u00e4\u00e4n l\u00e4ht\u00f6nopeudeksi. Tukijalalle t\u00f6rm\u00e4\u00e4minen jarruttaa heitt\u00e4j\u00e4n etenemisliikett\u00e4, jolloin kontaktin aikana tuotetaan suuria reaktiovoimia. Keih\u00e4\u00e4nheittosuorituskykyyn ja heiton pituuteen vaikuttavat heitt\u00e4j\u00e4n nopeus, keih\u00e4\u00e4n l\u00e4ht\u00f6nopeus ja lentoasento, tukijalan jarrutusty\u00f6n tehokkuus, heittok\u00e4den tekniikka sek\u00e4 heitt\u00e4j\u00e4n asento heittohetkell\u00e4. Sen sijaan tuotettujen reaktiovoimien merkityst\u00e4 heittosuorituskyvylle ei viel\u00e4 t\u00e4ysin ymm\u00e4rret\u00e4. Pro gradu -tutkielman tarkoituksena oli selvitt\u00e4\u00e4, onko reaktiovoimilla, tukijalan kinematiikalla tai heitt\u00e4j\u00e4n tulonopeudella yhteytt\u00e4 heittosuorituskykyyn mies- ja naiskeih\u00e4\u00e4nheitt\u00e4jill\u00e4. Tutkimukseen osallistui 11 mies- (ik\u00e4 24 \u00b1 3 v, pituus 184 \u00b1 8 cm, paino 96 \u00b1 12 kg, enn\u00e4tys 76.76 \u00b1 5.43 m) ja 13 naiskeih\u00e4\u00e4nheitt\u00e4j\u00e4\u00e4 (ik\u00e4 25 \u00b1 6 v, pituus 171 \u00b1 5 cm, paino 80 \u00b1 11 kg, enn\u00e4tys 55.79 \u00b1 5.85 m), jotka heittiv\u00e4t kuusi maksimaalista kilpailusuoritusta mukailevaa heittoa sis\u00e4tiloissa heittopressuun. Heitoista mitattiin reaktiovoimia voimalevyill\u00e4, ja reaktiovoimista analysoitiin vertikaalinen sek\u00e4 horisontaalinen huippuvoima, impulssi ja voimantuottonopeus. Heittovideoista analysoitiin heittoparametrit, kinemaattiset muuttujat sek\u00e4 tulonopeus. 3D-liikeanalyysin avulla. Heittoparametrien avulla heitoille laskettiin teoreettinen pituus. Miesheitt\u00e4jill\u00e4 horisontaalinen kehonpainoon suhteutettu huippuvoima oli yhteydess\u00e4 teoreettiseen heittopituuteen (r = -0.636, p = 0.035), keih\u00e4\u00e4n l\u00e4ht\u00f6nopeuteen (r = -0.609, p = 0.047) sek\u00e4 vetomatkaan (r = -0.624, p = 0.040). Askelpituuteen olivat yhteydess\u00e4 absoluuttinen vertikaalinen (r = 0.674, p = 0.023) ja horisontaalinen huippuvoima (r = -0.840, p = 0.001) sek\u00e4 kehonpainoon suhteutettu horisontaalinen huippuvoima (r = -0.818, p = 0.002). Naisheitt\u00e4jill\u00e4 reaktiovoimat eiv\u00e4t suoraan olleet yhteydess\u00e4 heittosuorituskykyyn, mutta irrotuskorkeuteen olivat yhteydess\u00e4 vertikaalinen (r = 0.721 p = 0.005) sek\u00e4 horisontaalinen (r = -0.607, p = 0.028) huippuvoima. Keih\u00e4\u00e4n l\u00e4ht\u00f6nopeuteen olivat yhteydess\u00e4 askelpituus (r = -0.560, p = 0.046) sek\u00e4 ristiaskelhypyn aikainen nilkkakorkeus (r = 0.582, p = 0.037). Tulonopeus ei ollut yhteydess\u00e4 heittosuorituskykyyn kummallakaan sukupuolella. Sek\u00e4 mies- ett\u00e4 naiskeih\u00e4\u00e4nheitt\u00e4jille horisontaalisesti suuntautuva jarrutusty\u00f6 vaikuttaisi olevan vertikaalista t\u00f6rm\u00e4\u00e4mist\u00e4 merkityksellisemp\u00e4\u00e4. Miesheitt\u00e4jien tulisi korostaa vaakasuuntaista jarrutusty\u00f6t\u00e4 heiton pituuden, keih\u00e4\u00e4n l\u00e4ht\u00f6nopeuden sek\u00e4 vetopituuden optimoimiseksi sek\u00e4 mahdollisesti hillit\u00e4 vertikaalista t\u00f6rm\u00e4\u00e4mist\u00e4 keih\u00e4\u00e4n asennon hallitsemiseksi. Askelpituutta pident\u00e4m\u00e4ll\u00e4 jarrutusty\u00f6t\u00e4 voidaan tehostaa, ja tulonopeuden kasvaessa jarrutusty\u00f6n vaatimus lis\u00e4\u00e4ntyy. Naisheitt\u00e4jill\u00e4 huippuvoimat saattavat selitt\u00e4\u00e4 heittosuorituskyky\u00e4 ep\u00e4suorasti, ja heitt\u00e4jien on kyett\u00e4v\u00e4 tuottamaan tarpeeksi voimaa korkean lantion asennon sek\u00e4 irrotuskorkeuden mahdollistamiseksi. Jarrutusty\u00f6t\u00e4 voidaan tehostaa astumalla tukijalan askel kantap\u00e4\u00e4voittoisesti. Optimaalisen keih\u00e4\u00e4n l\u00e4ht\u00f6nopeuden saavuttamiseksi tukijalan askelpituutta ei tule ylikorostaa.", "language": "fi", "element": "description", "qualifier": "abstract", "schema": "dc"}, {"key": "dc.description.provenance", "value": "Submitted by Miia Hakanen (mihakane@jyu.fi) on 2024-05-24T09:48:48Z\nNo. of bitstreams: 0", "language": "en", "element": "description", "qualifier": "provenance", "schema": "dc"}, {"key": "dc.description.provenance", "value": "Made available in DSpace on 2024-05-24T09:48:48Z (GMT). No. of bitstreams: 0\n Previous issue date: 2024", "language": "en", "element": "description", "qualifier": "provenance", "schema": "dc"}, {"key": "dc.format.extent", "value": "67", "language": "", "element": "format", "qualifier": "extent", "schema": "dc"}, {"key": "dc.language.iso", "value": "fin", "language": null, "element": "language", "qualifier": "iso", "schema": "dc"}, {"key": "dc.rights", "value": "In Copyright", "language": "en", "element": "rights", "qualifier": null, "schema": "dc"}, {"key": "dc.subject.other", "value": "heittoparametrit", "language": "", "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.subject.other", "value": "voimalevymittaus", "language": "", "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.title", "value": "Reaktiovoimien, tukijalan kinematiikan sek\u00e4 tulonopeuden yhteys heittosuorituskykyyn mies- ja naiskeih\u00e4\u00e4nheitt\u00e4jill\u00e4", "language": "", "element": "title", "qualifier": null, "schema": "dc"}, {"key": "dc.type", "value": "master thesis", "language": null, "element": "type", "qualifier": null, "schema": "dc"}, {"key": "dc.identifier.urn", "value": "URN:NBN:fi:jyu-202405243923", "language": null, "element": "identifier", "qualifier": "urn", "schema": "dc"}, {"key": "dc.type.ontasot", "value": "Master\u2019s thesis", "language": "en", "element": "type", "qualifier": "ontasot", "schema": "dc"}, {"key": "dc.type.ontasot", "value": "Pro gradu -tutkielma", "language": "fi", "element": "type", "qualifier": "ontasot", "schema": "dc"}, {"key": "dc.contributor.faculty", "value": "Faculty of Sport and Health Sciences", "language": "en", "element": "contributor", "qualifier": "faculty", "schema": "dc"}, {"key": "dc.contributor.faculty", "value": "Liikuntatieteellinen tiedekunta", "language": "fi", "element": "contributor", "qualifier": "faculty", "schema": "dc"}, {"key": "dc.contributor.department", "value": "Sport and Health Sciences", "language": "en", "element": "contributor", "qualifier": "department", "schema": "dc"}, {"key": "dc.contributor.department", "value": "Liikunta- ja terveystieteet", "language": "fi", "element": "contributor", "qualifier": "department", "schema": "dc"}, {"key": "dc.contributor.organization", "value": "University of Jyv\u00e4skyl\u00e4", "language": "en", "element": "contributor", "qualifier": "organization", "schema": "dc"}, {"key": "dc.contributor.organization", "value": "Jyv\u00e4skyl\u00e4n yliopisto", "language": "fi", "element": "contributor", "qualifier": "organization", "schema": "dc"}, {"key": "dc.subject.discipline", "value": "Science in Sport Coaching and Fitness Testing", "language": "en", "element": "subject", "qualifier": "discipline", "schema": "dc"}, {"key": "dc.subject.discipline", "value": "Valmennus- ja testausoppi", "language": "fi", "element": "subject", "qualifier": "discipline", "schema": "dc"}, {"key": "yvv.contractresearch.funding", "value": "0", "language": "", "element": "contractresearch", "qualifier": "funding", "schema": "yvv"}, {"key": "dc.type.coar", "value": "http://purl.org/coar/resource_type/c_bdcc", "language": null, "element": "type", "qualifier": "coar", "schema": "dc"}, {"key": "dc.rights.accesslevel", "value": "openAccess", "language": null, "element": "rights", "qualifier": "accesslevel", "schema": "dc"}, {"key": "dc.type.publication", "value": "masterThesis", "language": null, "element": "type", "qualifier": "publication", "schema": "dc"}, {"key": "dc.subject.oppiainekoodi", "value": "5013", "language": null, "element": "subject", "qualifier": "oppiainekoodi", "schema": "dc"}, {"key": "dc.subject.yso", "value": "biomekaniikka", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "yleisurheilu", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "liikeanalyysi", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.rights.url", "value": "https://rightsstatements.org/page/InC/1.0/", "language": null, "element": "rights", "qualifier": "url", "schema": "dc"}]
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