Effect of Unstable Loads on Stabilizing Muscles and Bar Motion During the Bench Press.
Journal
Journal of strength and conditioning research
ISSN: 1533-4287
Titre abrégé: J Strength Cond Res
Pays: United States
ID NLM: 9415084
Informations de publication
Date de publication:
01 Feb 2021
01 Feb 2021
Historique:
pubmed:
24
8
2018
medline:
15
4
2021
entrez:
24
8
2018
Statut:
ppublish
Résumé
Lawrence, MA, Ostrowski, SJ, Leib, DJ, and Carlson, LA. Effect of unstable loads on stabilizing muscles and bar motion during the bench press. J Strength Cond Res 35(2S): S120-S126, 2021-Unstable loads are anecdotally used to increase muscle stabilizer strength and utilization; however, there is little evidence to support these claims. Twelve male powerlifters (age 28.6 ± 5.2 years, body mass 105.6 ± 14.5 kg, lifting experience 9.8 ± 6.0 years, and bench press 5 repetition maximum [5RM] 133.6 ± 30.9 kg) pressed their 5RM in one stable condition with a standard barbell, and 3 unstable conditions using a flexible barbell with weights suspended from elastic bands. Mean integrated muscle activity for each repetition of the stabilizers and prime movers were measured. A Lyapunov exponent and sample entropy indicated unstable loads were less predictable and more variable in the superior/inferior direction, thus more challenging to control, despite decreased loads. The main finding was increased bicep activity in all unstable conditions (light bands and plates, +57%; mini bands and plates, +67%; and mini bands and kettlebells, +88%). Although less weight was used in the unstable 5RMs, most stabilizer muscle activity was not different between conditions, suggesting that the amount of weight used during unstable load training (up to 32.3% less load) may be limited by the ability of stabilizer muscles to control the load.
Identifiants
pubmed: 30138240
pii: 00124278-202102001-00019
doi: 10.1519/JSC.0000000000002788
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
S120-S126Informations de copyright
Copyright © 2018 National Strength and Conditioning Association.
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