Search results for "isometric"
showing 10 items of 535 documents
Decay spectroscopy of the very neutron-deficient lead and thallium isotopes 178,179Pb and ¹⁷⁹Tl
2018
This thesis reports on the production of the very neutron-deficient isotopes 178,179Pb and 179Tl, using heavy-ion fusion-evaporation reactions. The gas-filled separator RITU and the GREAT spectrometer at its focal plane position were used for the decay spectroscopy study. The α decay of 178Pb and its α-decay chain were studied through α-α correlations. The α-particle energy and half-life were measured for 178Pb as, Eα= 7610(30) keV and t1/2 = 0.21−+0.21 0.08 ms, respectively. The half-life is consistent with recent theoretical calculations using the Coulomb and Proximity Potential Model (CPPM). The hindrance factor for 178Pb was deduced and corresponds to an unhindered Δl = 0 transition. Th…
Unilateral Maximal Isometric Hex Bar Pull Test : Within-Session Reliability and Lower Body Force Production in Male and Female Freeski Athletes
2021
The aim of the study was to (1) assess the within-session reliability of a unilateral isometric hex bar pull (UIHBP) maximal voluntary contraction (MVC) test and, (2) determine unilateral isometric absolute peak force (PFabs) and relative peak force (PF) values in freeski athletes. Twenty-one male and eight female academy to national team freeskiers performed the novel UIHBP MVC task on a force plate and PFabs and relative PF were assessed (1000 Hz). Within-session measures of PFabs offered high reliability on left and right limbs for males (ICC = 0.91–0.94, CV = 2.6–2.2%) and females (ICC = 0.94–0.94, CV = 1.4–1.6%), while relative PF measures showed good to high reliability in both left a…
Individuality of responses to bilateral and unilateral volume equated hypertrophic strength training in physically active men
2019
Purpose. The purpose of the present study was to investigate possible differences between unilateral and bilateral strength training during ten weeks progressive hypertrophic strength training and six weeks detraining period. Furthermore, it was examined possible different individual responders in muscle hypertrophy during strength training and, how those different responders would behave during the detraining phase following the training period. Methods. The present intervention included ten weeks of progressive hypertrophic resistance training followed by six weeks of detraining in healthy young men (n=24). Ultrasound was used to measure vastus lateralis (VL) muscle cross-sectional area (…
Isometric force-time parameters in monitoring of strength training : with special reference to acute responses to different loading resistances
2017
The aim of the present series of studies was to investigate acute neuromuscular responses to (1) different strength training loadings and using (2) different external resistances. In addition, chronic adaptations and dynamic performances were compared to (3) the changes in isometric force-time parameters at the group level, and to (4) the individual timing of the improvement in the rate of force development (RFD) due to hypertrophic or maximum strength followed by power strength training periods. The latter one was achieved by systematic, repeated monitoring. Sixty-nine physically active men (20-35 yrs), but not experienced in resistance training, took part in the present series of studies.…
99 Muscle-tendon Properties During Recovery From Complete Achilles Tendon Rupture – A Case Study
2014
Introduction Achilles tendon is the most common tendon to suffer for complete rupture. Physically active young adults are often treated with surgery. Most of the patients do not suffer from activity limitations after injury 3 but performance level is often significantly decreased. 1,2 The purpose of this study was to follow recovery of Achilles tendon and triceps surae muscles after complete Achilles tendon rupture and subsequent surgery. This study served as a pilot phase for future research project. Methods Three subjects were recruited to this pilot phase of the study. Subjects were first time measured 2 to 8 months after injury and followed 6 to 8 months. Plantarflexion strength was mea…
Concentric and/or Eccentric Training-Induced Alterations in Shoulder Flexor and Extensor Strength
1997
To examine the effect of specific concentric and eccentric training on muscular strength following an initial standardized period of excessive training, shoulder extensors and flexors were tested. The shoulder is a joint particularly susceptible to injury and requires a specific strength training program. For a period of 12 weeks, subjects performed training, including concentric and eccentric actions. Thereafter, they were divided into three groups that performed specific 12-week programs, including either concentric (C-E/C), eccentric (C-E/E), or a combination of both concentric and eccentric exercises (C-E/C-E). Following the initial period of training, significant increases (p0.05) in p…
Motor unit discharge rate in dynamic movements of the aging soleus
2014
Aging is related to changes at the muscular level, leading to a decline in motor performance increasing the risk of falling and injury. It seems that the age-related changes in motor unit activation are muscle- and intensity dependent. The purpose of this study was to examine possible differences in soleus motor unit discharge rate (MUDR) in both isometric and dynamic contractions between young and elderly adults. 11 young (YOUNG) and 8 elderly (OLD) males participated in the study. The subjects performed isometric and dynamic plantar flexions while seated in an ankle dynamometer. The force levels studied were 10, 20, 40, 60, 80 and 100% of the isometric (ISO) MVC in ISO and 10, 20 and 40% …
Muscle hypertrophy, strength development, and serum hormones during strength training in elderly women with fibromyalgia.
2005
To examine the effects of strength training on maximal force, cross-sectional area (CSA), and electromyographic (EMG) activity of muscles and serum hormone concentrations in elderly females with fibromyalgia (FM).Twenty-six patients with FM were randomly assigned to a training (FMT; n = 13; mean age 60 years) or a control (FMC; n = 13; 59 years) group. FMT performed progressive strength training twice a week for 21 weeks. The measurements included maximal isometric and concentric leg extension forces, EMG activity of the vastus lateralis and medialis, CSA of the quadriceps femoris, and serum concentrations of testosterone (T), free testosterone (FT), growth hormone (GH), insulin-like growth…
Heritability of maximal isometric muscle strength in older female twins.
2003
The purpose of the present study was to examine genetic and environmental effects on maximal isometric handgrip, knee extension, and ankle plantar flexion strength. In addition, we wanted to investigate whether the strength of these three muscle groups shares a genetic component or whether the genetic effect is specific for each muscle group. Muscle strength was measured as part of the Finnish Twin Study on Aging in 97 monozygotic (MZ) and 102 dizygotic (DZ) female twin pairs, aged 63-76 yr. The MZ and DZ individuals did not differ from each other in age, body height, weight, or self-related health. The age-adjusted pairwise (intraclass) correlations of the MZ and DZ twins were, respective…
Effects of time of day on resistance exercise-induced anabolic signaling in skeletal muscle
2013
This study examined the effect of morning versus afternoon exercise on acute responses in phosphorylation of proteins regulating muscle size and metabolism. Twenty-two untrained men, divided into the morning (n = 11) or afternoon (n = 11) group, performed maximal isometric leg extensions before and after resistance loading at 07:30–08:30 h and 16:00–17:00 h, respectively. Muscle pre- and postloading biopsies were analyzed for phosphorylated Akt, p70S6K, rpS6, p38 mitogen-activated protein kinase (MAPK), Erk1/2, and eukaryotic elongation factor (eEF) 2. Muscle force declined after exercise in both groups (p < 0.001). p70S6K Thr389 (p < 0.05) and Thr421/Ser424 and rpS6 (all p < 0.001) increas…