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Musculotendinous stiffness of triceps surae, maximal rate of force development, and vertical jump performance.

Driss T, Lambertz D, Rouis M, Jaafar H, Vandewalle H - Biomed Res Int (2015)

Bottom Line: The subjects were subdivided in 3 groups in function of CMJ (groups H, M, and L for high, medium, and low performers, resp.).There was a downward curvature of the torque-stiffness relationship at high torques in group H or M and the torque-stiffness regression was linear in group L only.These results suggested that torque-stiffness relationships with a plateau at high torques are more frequent in the best jumpers.

View Article: PubMed Central - PubMed

Affiliation: CeRSM (EA 2931), Equipe de Physiologie, Biomécanique et Imagerie du Mouvement, UFR STAPS, Université Paris Ouest Nanterre La Défense, 200 avenue de la République, 92000 Nanterre, France.

ABSTRACT
The relationships between ankle plantar flexor musculotendinous stiffness (MTS) and performance in a countermovement vertical jump (CMJ) and maximal rate of torque development (MRTD) were studied in 27 active men. MTS was studied by means of quick releases at 20 (S0.2), 40 (S0.4), 60 (S0.6), and 80% (S0.8) of maximal voluntary torque (T(MVC)). CMJ was not correlated with strength indices but was positively correlated with MRTD/BM, S 0.4/BM. The slope α 2 and intercept β 2 of the torque-stiffness relationships from 40 to 80% T(MVC) were correlated negatively (α 2) and positively (β 2) with CMJ. The different stiffness indices were not correlated with MRTD. The prediction of CMJ was improved by the introduction of MRTD in multiple regressions between CMJ and stiffness. CMJ was also negatively correlated with indices of curvature of the torque-stiffness relationship. The subjects were subdivided in 3 groups in function of CMJ (groups H, M, and L for high, medium, and low performers, resp.). There was a downward curvature of the torque-stiffness relationship at high torques in group H or M and the torque-stiffness regression was linear in group L only. These results suggested that torque-stiffness relationships with a plateau at high torques are more frequent in the best jumpers.

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Relationship between vertical jump (CMJ) and the indices of curvature (ratio α2/α1, TC) of the torque-stiffness relationship. The same symbols as in Figure 4.
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fig5: Relationship between vertical jump (CMJ) and the indices of curvature (ratio α2/α1, TC) of the torque-stiffness relationship. The same symbols as in Figure 4.

Mentions: Ratio α2/α1 was close to 1 in group L and was independent of maximal strength indices (TMVC, TMVC/BM, r < 0.049) and torque development (MRTD, MRTD/BM, and MRTD/TMVC; r < 0.225). Interestingly, CMJ was significantly and negatively correlated with ratio α2/α1 or curvature index TC (Figure 5):(9)CMJ=73.8−5.28α2α1 r=0.467; P=0.014,CMJ=87.8−42.5TC r=0.574; P=0.002.


Musculotendinous stiffness of triceps surae, maximal rate of force development, and vertical jump performance.

Driss T, Lambertz D, Rouis M, Jaafar H, Vandewalle H - Biomed Res Int (2015)

Relationship between vertical jump (CMJ) and the indices of curvature (ratio α2/α1, TC) of the torque-stiffness relationship. The same symbols as in Figure 4.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4325552&req=5

fig5: Relationship between vertical jump (CMJ) and the indices of curvature (ratio α2/α1, TC) of the torque-stiffness relationship. The same symbols as in Figure 4.
Mentions: Ratio α2/α1 was close to 1 in group L and was independent of maximal strength indices (TMVC, TMVC/BM, r < 0.049) and torque development (MRTD, MRTD/BM, and MRTD/TMVC; r < 0.225). Interestingly, CMJ was significantly and negatively correlated with ratio α2/α1 or curvature index TC (Figure 5):(9)CMJ=73.8−5.28α2α1 r=0.467; P=0.014,CMJ=87.8−42.5TC r=0.574; P=0.002.

Bottom Line: The subjects were subdivided in 3 groups in function of CMJ (groups H, M, and L for high, medium, and low performers, resp.).There was a downward curvature of the torque-stiffness relationship at high torques in group H or M and the torque-stiffness regression was linear in group L only.These results suggested that torque-stiffness relationships with a plateau at high torques are more frequent in the best jumpers.

View Article: PubMed Central - PubMed

Affiliation: CeRSM (EA 2931), Equipe de Physiologie, Biomécanique et Imagerie du Mouvement, UFR STAPS, Université Paris Ouest Nanterre La Défense, 200 avenue de la République, 92000 Nanterre, France.

ABSTRACT
The relationships between ankle plantar flexor musculotendinous stiffness (MTS) and performance in a countermovement vertical jump (CMJ) and maximal rate of torque development (MRTD) were studied in 27 active men. MTS was studied by means of quick releases at 20 (S0.2), 40 (S0.4), 60 (S0.6), and 80% (S0.8) of maximal voluntary torque (T(MVC)). CMJ was not correlated with strength indices but was positively correlated with MRTD/BM, S 0.4/BM. The slope α 2 and intercept β 2 of the torque-stiffness relationships from 40 to 80% T(MVC) were correlated negatively (α 2) and positively (β 2) with CMJ. The different stiffness indices were not correlated with MRTD. The prediction of CMJ was improved by the introduction of MRTD in multiple regressions between CMJ and stiffness. CMJ was also negatively correlated with indices of curvature of the torque-stiffness relationship. The subjects were subdivided in 3 groups in function of CMJ (groups H, M, and L for high, medium, and low performers, resp.). There was a downward curvature of the torque-stiffness relationship at high torques in group H or M and the torque-stiffness regression was linear in group L only. These results suggested that torque-stiffness relationships with a plateau at high torques are more frequent in the best jumpers.

Show MeSH
Related in: MedlinePlus