Abstract：
:This study examined the validity of 2 kinematic systems for estimating force and power during squat jumps. 12 weight-trained males each performed single repetition squat jumps with a 20-kg, 40-kg, 60-kg and 80-kg load on a Kistler portable force plate. A commercial linear position transducer (Gymaware [GYM]) and accelerometer (Myotest® [MYO]) were attached to the bar to assess concentric peak force (PF) and peak power (PP). Across all loads tested, the GYM and MYO estimates of PF and PP were moderately to strongly correlated ( P≤0.05-0.001) with the force plate measurements ( R=0.59-0.87 and R=0.66-0.97), respectively. The mean PF and PP values were not significantly different between the 2 kinematic systems and the force plate, but the estimates did produce some systematic bias and relatively large random errors, especially with the 20-kg load (PF bias >170 N, PF error >335 N, PP bias >400 W, PP error >878 W). Some proportional bias was also identified. In summary, the estimation of PF and PP by a linear position transducer and accelerometer showed moderate to strong relative validity and equivalent absolute validity, but these estimates are limited by the presence of bias and large random errors.
journal_name
Int J Sports Medjournal_title
International journal of sports medicineauthors
Crewther BT,Kilduff LP,Cunningham DJ,Cook C,Owen N,Yang GZdoi
10.1055/s-0030-1270487subject
Has Abstractpub_date
2011-04-01 00:00:00pages
254-8issue
4eissn
0172-4622issn
1439-3964journal_volume
32pub_type
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journal_title：International journal of sports medicine
pub_type： 杂志文章
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journal_title：International journal of sports medicine
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journal_title：International journal of sports medicine
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更新日期：1997-01-01 00:00:00
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journal_title：International journal of sports medicine
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journal_title：International journal of sports medicine
pub_type： 杂志文章
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journal_title：International journal of sports medicine
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journal_title：International journal of sports medicine
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journal_title：International journal of sports medicine
pub_type： 临床试验,杂志文章
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更新日期：2005-09-01 00:00:00
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journal_title：International journal of sports medicine
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pub_type： 临床试验,杂志文章,随机对照试验
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pub_type： 杂志文章,随机对照试验
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journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2007-971089
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journal_title：International journal of sports medicine
pub_type： 杂志文章
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pub_type： 杂志文章
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journal_title：International journal of sports medicine
pub_type： 杂志文章
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journal_title：International journal of sports medicine
pub_type： 杂志文章,随机对照试验
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更新日期：2013-04-01 00:00:00
