Search results for "Isometric exercise"
showing 10 items of 449 documents
Non-uniformity of displacement and strain within the Achilles tendon is affected by joint angle configuration and differential muscle loading.
2020
Although the Achilles tendon (AT) has been studied for more than a century, a complete understanding of the mechanical and functional consequences of AT structural organization is currently lacking. The aim of this study was to assess how joint angle configuration affects subtendon displacement and strain of soleus (SOL) and lateral gastrocnemius (LG) muscles. Knots sutured onto SOL and LG subtendons of 12 Wistar rats, were videotaped to quantify displacements and the ankle torque was assessed for different isometric activation conditions (i.e., individual and simultaneous) of the triceps surae muscles. Changing ankle and knee joint angle affected the magnitude of displacement, relative dis…
Maximal isometric muscle strength and functional ability in daily activities among 75-year-old men and women
2007
The purpose of this study was to analyze whether functional ability in daily activities among 75-year-old men and women is predicted by physical activity, isometric muscle strength and simple function tests. In this representative sample of a general population of 405 75-year-olds, isometric muscle strength and functional ability in daily activities were closely related (odds ratio of disability 1.2–2.1), stressing the importance of strength in the truncus, proximal and distal muscle groups for daily activities. There were strong correlations between physical activity, isometric muscle strength as well as simple function tests and ability to manage daily activities. Those with even light ph…
Comparison of the roles of common constitutional and behavioural parameters in back performance estimates
2006
Objective: To compare the associations between different physical activity histories and anthropometric measures in isokinetic lifting performance, isometric back extension endurance and psychophysical lifting tests. Background: The relative roles and interaction of these factors related to back function are largely unknown. Methods: The subjects consisted of a population-based sample of 210 working-age males. Paraspinal muscle cross-sectional areas were obtained by magnetic resonance imaging; anthropometric measures, isokinetic and psychophysical lifting capacity, and isometric back extension endurance tests were performed and current and physical activity histories and occupational loadin…
Influence of Oral Contraceptive Use on Adaptations to Resistance Training
2019
Introduction: The majority of young women use oral contraceptives (OCs). Use of OCs has been associated with lower myofibrillar protein and tendon collagen synthesis rates, but it is unknown whether OCs will limit the adaptive response of myotendinous tissue to resistance training. Design and Methods: Fourteen healthy untrained young regular OC users (24 +/- 1 years, fat% 32 +/- 1, 35 +/- 2 ml.min(-1).kg(-1)) and 14 NOC users (non-OC, controls) (24 +/- 1 years, fat% 32 +/- 2, 34 +/- 2 ml.min(-1).kg(-1)) performed a 10-week supervised lower extremity progressive resistance training program. Before and after the intervention biopsies from the vastus lateralis muscle and the patellar tendon we…
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…
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…
A comparison of elastic tubing and isotonic resistance exercises.
2010
The aim of this study was to assess eff ects of a short-term resistance program on strength in fi t young women using weight machines / free weights or elastic tubing. 42 physically fi t women (21.79 ± 0.7 years) were randomly assigned to the following groups: (i) the Thera-Band ® Exercise Station Group (TBG); (ii) the weight machines / free weights group (MFWG); or (iii) the control group (CG). Each experimental group performed the same periodised training program that lasted for 8 weeks, with 2 – 4 sessions per week and 3 – 4 sets of 8 – 15 submaximal reps. A load cell (Isocontrol; ATEmicro, Madrid, Spain) was used to test the evolution of the Maximum Isometric Voluntary Contraction (MIVC…