PMID- 26664263
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20151215
LR  - 20181113
IS  - 1303-2968 (Print)
IS  - 1303-2968 (Electronic)
IS  - 1303-2968 (Linking)
VI  - 14
IP  - 4
DP  - 2015 Dec
TI  - Relationships Between Lower-Body Muscle Structure and, Lower-Body Strength, 
      Explosiveness and Eccentric Leg Stiffness in Adolescent Athletes.
PG  - 691-7
AB  - The purpose of the present study was to determine whether any relationships were 
      present between lower-body muscle structure and, lower-body strength, variables 
      measured during a countermovement jump (CMJ) and squat jump (SJ), and eccentric 
      leg stiffness, in adolescent athletes. Thirty junior male (n = 23) and female (n 
      = 7) surfing athletes (14.8 +/- 1.7 y; 1.63 +/- 0.09 m; 54.8 +/- 12.1 kg) undertook 
      lower-body muscle structure assessment with ultrasonography and performed a; CMJ, 
      SJ and an isometric mid-thigh pull (IMTP). In addition, eccentric leg stiffness 
      was calculated from variables of the CMJ and IMTP. Moderate to very large 
      relationships (r = 0.46-0.73) were identified between the thickness of the vastus 
      lateralis (VL) and lateral gastrocnemius (LG) muscles, and VL pennation angle 
      and; peak force (PF) in the CMJ, SJ and IMTP. Additionally, moderate to large 
      relationships (r = 0.37-0.59) were found between eccentric leg stiffness and; VL 
      and LG thickness, VL pennation angle, and LG fascicle length, with a large 
      relationship (r = 0.59) also present with IMTP PF. These results suggest that 
      greater thickness of the VL and LG were related to improved maximal dynamic and 
      isometric strength, likely due to increased hypertrophy of the extensor muscles. 
      Furthermore, this increased thickness was related to greater eccentric leg 
      stiffness, as the associated enhanced lower-body strength likely allowed for 
      greater neuromuscular activation, and hence less compliance, during a 
      stretch-shortening cycle. Key pointsGreater thickness of the VL and LG muscles 
      were significantly related to an enhanced ability to express higher levels of 
      isometric and dynamic strength, and explosiveness in adolescent 
      athletes.Isometric strength underpinned performance in the CMJ and SJ in these 
      athletes.Greater lower-body isometric strength was significantly related to 
      eccentric leg stiffness, which is potentially the result of greater neuromuscular 
      activation in the muscle-tendon unit.
FAU - Secomb, Josh L
AU  - Secomb JL
AD  - Hurley Surfing Australia High Performance Centre , Casuarina Beach, Australia ; 
      Centre for Exercise and Sport Science Research, Edith Cowan University , 
      Joondalup, Australia.
FAU - Nimphius, Sophia
AU  - Nimphius S
AD  - Centre for Exercise and Sport Science Research, Edith Cowan University , 
      Joondalup, Australia.
FAU - Farley, Oliver R L
AU  - Farley OR
AD  - Hurley Surfing Australia High Performance Centre , Casuarina Beach, Australia ; 
      Centre for Exercise and Sport Science Research, Edith Cowan University , 
      Joondalup, Australia.
FAU - Lundgren, Lina E
AU  - Lundgren LE
AD  - Hurley Surfing Australia High Performance Centre , Casuarina Beach, Australia ; 
      Centre for Exercise and Sport Science Research, Edith Cowan University , 
      Joondalup, Australia.
FAU - Tran, Tai T
AU  - Tran TT
AD  - Hurley Surfing Australia High Performance Centre , Casuarina Beach, Australia ; 
      Centre for Exercise and Sport Science Research, Edith Cowan University , 
      Joondalup, Australia.
FAU - Sheppard, Jeremy M
AU  - Sheppard JM
AD  - Hurley Surfing Australia High Performance Centre , Casuarina Beach, Australia ; 
      Centre for Exercise and Sport Science Research, Edith Cowan University , 
      Joondalup, Australia.
LA  - eng
PT  - Journal Article
DEP - 20151124
PL  - Turkey
TA  - J Sports Sci Med
JT  - Journal of sports science & medicine
JID - 101174629
PMC - PMC4657409
OTO - NOTNLM
OT  - Muscle architecture
OT  - associations
OT  - children
OT  - ultrasound
EDAT- 2015/12/15 06:00
MHDA- 2015/12/15 06:01
PMCR- 2015/11/24
CRDT- 2015/12/15 06:00
PHST- 2015/06/30 00:00 [received]
PHST- 2015/07/23 00:00 [accepted]
PHST- 2015/12/15 06:00 [entrez]
PHST- 2015/12/15 06:00 [pubmed]
PHST- 2015/12/15 06:01 [medline]
PHST- 2015/11/24 00:00 [pmc-release]
AID - jssm-14-691 [pii]
PST - epublish
SO  - J Sports Sci Med. 2015 Nov 24;14(4):691-7. eCollection 2015 Dec.