Search results for " isometric"

Determining the optimal maximal and submaximal voluntary contraction tests for normalizing the erector spinae muscles

2019

Background This study aimed to identify which maximum voluntary isometric contraction (MVIC) and sub-MVIC tests produce the highest activation of the erector spinae muscles and the greatest reduction in inter-individual variability, to put them forward as reference normalization maneuvers for future studies. Methods Erector spinae EMG activity was recorded in 38 healthy women during five submaximal and three maximal exercises. Results None of the three MVIC tests generated the maximal activation level in all the participants. The maximal activation level was achieved in 68.4% of cases with the test performed on the roman chair in the horizontal position (96.3 ± 7.3; p < 0.01). Of the fi…

Boundary quotients and ideals of Toeplitz C∗-algebras of Artin groups

2006

We study the quotients of the Toeplitz C*-algebra of a quasi-lattice ordered group (G,P), which we view as crossed products by a partial actions of G on closed invariant subsets of a totally disconnected compact Hausdorff space, the Nica spectrum of (G,P). Our original motivation and our main examples are drawn from right-angled Artin groups, but many of our results are valid for more general quasi-lattice ordered groups. We show that the Nica spectrum has a unique minimal closed invariant subset, which we call the boundary spectrum, and we define the boundary quotient to be the crossed product of the corresponding restricted partial action. The main technical tools used are the results of …

On the quasi-isometric and bi-Lipschitz classification of 3D Riemannian Lie groups.

2021

AbstractThis note is concerned with the geometric classification of connected Lie groups of dimension three or less, endowed with left-invariant Riemannian metrics. On the one hand, assembling results from the literature, we give a review of the complete classification of such groups up to quasi-isometries and we compare the quasi-isometric classification with the bi-Lipschitz classification. On the other hand, we study the problem whether two quasi-isometrically equivalent Lie groups may be made isometric if equipped with suitable left-invariant Riemannian metrics. We show that this is the case for three-dimensional simply connected groups, but it is not true in general for multiply connec…

Angular momentum population in fragmentation reactions

2009

Neutron-deficient nuclei with N = 126 have been populated following projectile fragmentation of a 238U beam with energy 1 GeV/A. The decay of several previously reported isomers has been measured. This will allow us to calculate high-spin isomeric ratios and compare them with model calculations to allow a better understanding of the reaction mechanism. Algora, Alejandro, Alejandro.Algora@ific.uv.es ; Molina Palacios, Francisco Manuel, Francisco.Molina@ific.uv.es ; Rubio Barroso, Berta, Berta.Rubio@ific.uv.es

Power training in young athletes: Is it all in the genes?

2018

Introduction. The aim of the study was to evaluate the effects of plyometric and isometric training protocol on power in 46 team sports (basketball: n = 23; volleyball: n = 23) players, also in relation to genetic background (i.e., ACE and PPARA genes polymorphisms). Methods. The following tests were administered: squat jump (SJ), countermovement jump (CMJ), drop jump (dJ), sprint, handgrip, and agility test. Genetic analysis was based on saliva samples. Results. The training protocol proved to be effective in improving jump performance in basketball players and volleyball players, respectively: 25-meter sprint test (p = 0.006; p = 0.008); agility test (p = 0.000; p = 0.000); SJ test (p = 0…

The Effect of the Cranial Electrotherapy on the Muscle Motor Function in Different Operating Modes

2015

The aim of the present study was to analyze the effect of cranial electrotherapy stimulation on muscle function analysis indicators. Instrumental assessment of muscle function (on a REV9000, Technogym, Italy) was performed before and after cranial electrotherapy stimulation, assessments of the muscle function was performed during knee extension maximum voluntary, isometric contraction (MVIC), angle velocity with load 45Nm isotonic contraction and maximum pick torque in isokinetic contraction on 30°/s, 200°/s and 300°/s and neuromuscular efficiency measurements. To analyze data was used Excel program Statistics 3.1. Subjects of our study were twenty healthy athletes of sport fitness. 1 minu…

Can Vitamin D deficiency influence muscle perfomance in post-menopausal women? A multicenter retrospective study

2018

Background: The presence of the vitamin D receptor (VDR) has been recently demonstrated in human muscle supporting the theory of a role of vitamin D in the proliferation and differentiation of muscle cells. So far only few studies investigated the association between vitamin D and muscle performance in postmenopausal women. Aim: To define the functional impact of vitamin D deficiency. Design: Multicenter retrospective study. Setting: Five Italian outpatient services of Physical and Rehabilitation Medicine (PRM). Population: Postmenopausal women. Methods: We divided the population in two groups based on the threshold of 30 ng/mL as cut-off to define sufficient and insufficient serum levels o…

Physical and Quality of Life Changes in Elderly Patients after Laparoscopic Surgery for Colorectal Cancer—A Prospective Cohort Study

2022

Background—The incidence of colorectal cancer is increasing among elderly people, where postoperative complications are frequent. Methods—We evaluated postoperative physical and quality of life changes in elderly patients undergoing laparoscopic surgery for colorectal cancer. A prospective cohort study was performed in 31 colorectal cancer patients ≥60 years who were scheduled for laparoscopic surgery due to colorectal cancer. Outcomes were measured one month preoperative (T1), three days postoperative (T2) and one month postoperative (T3). Results—The largest early postoperative (from T1 to T2) declines were observed for isometric knee extension strength (33.1%), 30 s …

The acute effects of different high-intensity conditioning activities on sprint performance differ between sprinters of different strength and power …

2021

The purpose of the present study was to examine the effect of different conditioning activities (CAs) on short-term increase in sprint performance. In twelve male sprinters (21.1+2.6 years, 100 m performance: 11.5+0.6 s) their body composition, half squat maximum strength, 100 m sprinting and countermovement jump performances were evaluated. The performance of a 50 m sprint (splits at 10 m, 30 m and 50 m) was evaluated before and 5, 10 and 15 min after four postactivation performance enhancement CAs on different occasions: [1] 3 sets x 4 s maximum isometric half squat (IHF), [2] 3 sets x 3 consecutive countermovement jumps (cCMJs), [3] 3 repetitions x 30 m overspeed sprinting (OVSP) and [4]…

Power training in young athletes: Is it all in the genes?

2018