electromyographic evidence, the side-bridge exercise is the most effective technique to simultaneously activate the muscular spine stabilizers such as the external oblique (EO), internal oblique (IO), and quadratus lumborum (QL). 4 During this exercise, the 3 layers of the abdominal wall (the EO, IO, and
Chi-Whan Choi, Jung-Wan Koo and Yeon-Gyu Jeong
Paul F. Greene, Christopher J. Durall and Thomas W. Kernozek
A torso-elevated side support (TESS) has previously been described for measuring endurance of the lateral trunk muscles. In some individuals, however, TESS performance may be hindered by upper extremity pain or fatigue. For this reason a novel test, the feet-elevated side-support test (FESS), was examined.
To determine intersession reliability of a FESS and a TESS on the left and right sides using a single examiner, to evaluate the relationship between tests, and to compare reasons for test termination.
Nonexperimental prospective repeated measures.
A convenience sample of 60 healthy participants from a university community (17 men, 43 women; age 21.1 ± 2.2 y; height 169.9 ± 9.5 cm; weight 67.1 ± 11.9 kg).
Intraclass correlation coefficient between 3 testing sessions = .87 with right FESS, .86 with left FESS, .78 with right TESS, and .91 with left TESS. Pearson correlation coefficients ranged from .59 (between left FESS and left TESS in women) to .75 (between left FESS and left TESS in men). Upper extremity pain or fatigue was the reason given for test termination in 42.5% of participants during the TESS and 5.0% during the FESS (P = .000, Fisher exact test).
FESS and TESS had comparable intersession reliability by the same evaluator. Moderate to high correlations were found between FESS and TESS scores, suggesting that the tests assess similar qualities. Far fewer participants terminated the FESS because of upper extremity pain or fatigue. Thus, the FESS may be a suitable alternative to the previously validated TESS, particularly for individuals with upper extremity pain or weakness.
John M. Mayer, James E. Graves, Todd M. Manini, James L. Nuzzo and Lori L. Ploutz-Snyder
The purpose of this preliminary study was to assess lumbar multifidus, erector spinae, and quadratus lum-borum muscle activity during lifts as measured by changes in transverse relaxation time (T2) from magnetic resonance imaging (MRI). Thirteen healthy adults performed dynamic squat, stoop, and asymmetric stoop lifts at a standard load, with each lift followed by MRI. Increase in T2 for the multifidus and erector spinae was greater for the stoop than squat. No difference in T2 increase was noted between the multifidus and erector spinae for the squat or stoop. Increase in T2 for the contralateral multifidus was less for the asymmetric stoop than stoop. Future research using MRI and other biomechanical techniques is needed to fully characterize lumbar muscle activity during lifts for various populations, settings, postures, and loads.
Renan Lima Monteiro, Joana Hoverter Facchini, Diego Galace de Freitas, Bianca Callegari and Sílvia Maria Amado João
Pelvic-drop exercises are often used to strengthen the gluteus medius (GM) muscle with the aim of increasing or prioritizing its recruitment. However, the effect of hip rotation on the performance of the action of the GM is unknown.
To evaluate the effect of hip rotation on the recruitment of the GM, tensor fasciae latae (TFL), and quadratus lumborum (QL).
Seventeen healthy subjects performed 2 sets of 4 repetitions of pelvic-drop exercise in random order with pelvic-drop lateral, medial, and neutral rotation of the hip.
Main Outcome Measures:
The electromyographic (EMG) activity of the GM, TFL, and QL was evaluated using surface electromyography.
There were significant increases in the activation of the GM with medial and neutral rotation compared with lateral rotation (P = .03, P = .01, respectively), and there was no difference between medial and neutral rotation (P = 1.00). There was no difference in EMG activity of the TFL and QL in any of the positions. The GM:TFL ratio was the same in all analyzed positions. Regarding the GM:QL ratio, there was a significant increase with medial rotation compared with lateral rotation (P = .02).
Pelvic-drop exercises are more efficient for activating the GM when the hip is in medial rotation and neutral position.
Kristi Edgar, Aimee Appel, Nicholas Clay, Adam Engelsgjerd, Lauren Hill, Eric Leeseberg, Allison Lyle and Erika Nelson-Wong
bracing and altered muscle activation patterns supports the hypothesis that SIJ bracing may impact the neural control subsystem, which aids in determining and implementing a stability strategy for a given movement scenario. Park et al 26 concluded that SIJ bracing modified GMed and quadratus lumborum
Billy Chun-Lung So, Calvin Hong-Nin Yuen, Ken Long-Hin Tung, Sheena Lam, Sammy Lan Cheng, Zina Wing-Lam Hung, Rainy Wai-Kwan Leung and Grace Pui-Yuk Szeto
, Kropf P . Appropriately placed surface EMG electrodes reflect deep muscle activity (psoas, quadratus lumborum, abdominal wall) in the lumbar spine . J Biomechan . 1996 ; 29 ( 11 ): 1503 – 1507 . doi:10.1016/0021-9290(96)84547-7 10.1016/0021-9290(96)84547-7 15. Larivière C , Arsenault AB
Lukas D. Linde, Jessica Archibald, Eve C. Lampert and John Z. Srbely
. PubMed ID: 15922235 doi:10.1016/j.math.2004.08.011 10.1016/j.math.2004.08.011 15. McGill SM , Juker D , Kropf JD . Appropriately place surface EMG electrodes reflect deep muscle activity (psoas, quadratus lumborum, abdominal wall) in the lumbar spine . J Biomech . 1996 ; 29 : 1503 – 1507