Search results for "train"
showing 10 items of 4562 documents
FGFR2mutation in 46,XY sex reversal with craniosynostosis
2015
Patients with 46,XY gonadal dysgenesis (GD) exhibit genital anomalies, which range from hypospadias to complete male-to-female sex reversal. However, a molecular diagnosis is made in only 30% of cases. Heterozygous mutations in the human FGFR2 gene cause various craniosynostosis syndromes including Crouzon and Pfeiffer, but testicular defects were not reported. Here, we describe a patient whose features we would suggest represent a new FGFR2-related syndrome, craniosynostosis with XY male-to-female sex reversal or CSR. The craniosynostosis patient was chromosomally XY, but presented as a phenotypic female due to complete GD. DNA sequencing identified the FGFR2c heterozygous missense mutatio…
Effects of muscle activation on shear between human soleus and gastrocnemius muscles
2015
Lateral connections between muscles provide pathways for myofascial force transmission. To elucidate whether these pathways have functional roles in vivo, we examined whether activation could alter the shear between the soleus (SOL) and lateral gastrocnemius (LG) muscles. We hypothesized that selective activation of LG would decrease the stretch-induced shear between LG and SOL. Eleven volunteers underwent a series of knee joint manipulations where plantar flexion force, LG, and SOL muscle fascicle lengths and relative displacement of aponeuroses between the muscles were obtained. Data during a passive full range of motion were recorded, followed by 20° knee extension stretches in both pass…
Musculoskeletal Pain in Gymnasts: A Retrospective Analysis on a Cohort of Professional Athletes
2021
Gymnastics athletes are exposed to a high risk of injury, but also of developing musculoskeletal pain. These data are still little investigated in the available scientific literature. An online survey was distributed to 79 professional athletes who practiced artistic and rhythmic gymnastics. The survey collected demographic and anthropometric data, information about the sport practice, the training sessions, the prevalence of musculoskeletal pain gymnastics-related, and lifestyle habits. Musculoskeletal pain had a high prevalence, involving 65 of 79 athletes (82.3%). A significant correlation was found between musculoskeletal pain and the duration of sports practice, both for general pain (…
Gastrocnemius tendon length and strain are different when assessed using straight or curved tendon model
2011
The present study investigated the effects of tendon curvature on measurements of tendon length using 3D-kinematic analysis. Curved and straight tendon models were employed for assessing medial gastrocnemius tendon length and strain during hopping (N = 8). Tendon curvature was identified using small reflective markers placed on the skin surface along the length of the tendon and a sum of vectors between the markers from the calcaneous up to the marker at the origin of tendon was calculated. The straight tendon was defined as a length of vector from the calcaneous to the marker at the origin of tendon. The curved tendon method yielded 5.0 ± 1.3 mm longer tendon (p < 0.001) than the straight …
Stiffness and Reinforcement Effect of electrical Resistance Strain Gauges
2007
: The increasing use of low-modulus materials, on which the reinforcement effect of the electrical resistance strain gauge is not negligible, has re-opened the research interest into this issue. This study deals with the evaluation of stiffness, and of the strain gauge Young's modulus involved in the estimation of both the global and the local reinforcement effect; the relationship between the strain gauge stiffness and the local reinforcement effect is also analysed. In particular, the experimental technique used to determine the stiffness of some commercial strain gauges is described. The results show that the strain gauge stiffness alone does not permit an accurate evaluation of the loc…
Effects of internal kinetics and muscle activity during the wide and narrow barbell back squat
2017
Lahti, J. 2017. Effects of internal kinetics and muscle activity during the wide and narrow barbell back squat. Sports biology department, University of Jyväskylä. Master’s thesis. p. 102 (4 attachments). Introduction. The barbell back squat (BBS) is a commonly utilized strength exercise to support general preparedness for the demands in multiple sports. Recently, studies have shown various strength training exercises have the potential to recruit the regions of the hamstrings differently. Specifically, it is unknown if changing stance width under conditions where forward knee movement is restricted engages the hamstring regions differently and how this corresponds with measured 3-D net joi…
Duchenne Muscular Dystrophy (DMD): Should it be Considered a Systemic Disease?
2016
Duchenne muscular dystrophy (DMD) is an X-linked muscle disease characterized by progressive skeletal muscle loss and development of respiratory failure due to involvement of respiratory muscles. Similar to human DMD, the mdx mouse model lacks dystrophin but is characterized by relatively mild muscle injury, allowing testing the effects of mild endurance exercise training on dystrophic skeletal muscle. We were interested to study the effects of exercise training on airway cells in trained mdx mice by applying the same protocol previously tested in Swiss mice. We found that mdx mice showed little airway inflammation associated with training, but developed increasing apoptosis of airway cells…
Effect of Training-Induced Changes in Achilles Tendon Stiffness on Muscle–Tendon Behavior During Landing
2018
During rapid deceleration of the body, tendons buffer part of the elongation of the muscle–tendon unit (MTU), enabling safe energy dissipation via eccentric muscle contraction. Yet, the influence of changes in tendon stiffness within the physiological range upon these lengthening contractions is unknown. This study aimed to examine the effect of training-induced stiffening of the Achilles tendon on triceps surae muscle–tendon behavior during a landing task. Twenty-one male subjects were assigned to either a 10-week resistance-training program consisting of single-leg isometric plantarflexion (n = 11) or to a non-training control group (n = 10). Before and after the training period, plantarf…
Training-induced increase in Achilles tendon stiffness affects tendon strain pattern during running
2019
Background During the stance phase of running, the elasticity of the Achilles tendon enables the utilisation of elastic energy and allows beneficial contractile conditions for the triceps surae muscles. However, the effect of changes in tendon mechanical properties induced by chronic loading is still poorly understood. We tested the hypothesis that a training-induced increase in Achilles tendon stiffness would result in reduced tendon strain during the stance phase of running, which would reduce fascicle strains in the triceps surae muscles, particularly in the mono-articular soleus. Methods Eleven subjects were assigned to a training group performing isometric single-leg plantarflexion co…
Changes in spinal range of motion after a flexibility training program in elderly women
2014
Giuseppe Battaglia,1,2 Marianna Bellafiore,1,2 Giovanni Caramazza,2 Antonio Paoli,3 Antonino Bianco,1,2 Antonio Palma1,2 1Department of Law, Society, and Sport Sciences, University of Palermo, Palermo, Italy; 2Sicilian Regional Sports School of Italian National Olympic Committee (CONI), Sicily, Italy; 3Department of Biomedical Sciences, University of Padova, Padova, Italy Background: Aging-related reduced spinal mobility can interfere with the execution of important functional skills and activities in elderly women. Although several studies have shown positive outcomes in response to spinal flexibility training programs, little is known about the management of sets and repetitions in traini…