Search results for "Muscle"
showing 10 items of 3397 documents
Physical fitness and volume of leisure time physical activity relate with low stress and high mental resources in young men.
2014
AIM: There is limited evidence available regarding the relationship between physical fitness, especially muscular fitness, and the mental well-being among young healthy men. Therefore, the aim of the present study was to investigate the impact of measured cardiovascular and muscle fitness and self reported leisure time physical activity (LTPA) on outcomes of stress and mental resources in Finnish young men. METHODS: In a cross-sectional study, 831 men (mean age 25 y) underwent cardiovascular and muscle fitness test and completed LTPA and Occupational Stress Questionnaires (OSQ). For analysis, the subjects were divided to LTPA, CVF and MFI tertiles. RESULTS: The group with low LTPA reported …
In vivo fascicle behavior of the flexor hallucis longus muscle at different walking speeds.
2017
Ankle plantar flexor muscles support and propel the body in the stance phase of locomotion. Besides the triceps surae, flexor hallucis longus muscle (FHL) may also contribute to this role, but very few in vivo studies have examined FHL function during walking. Here, we investigated FHL fascicle behavior at different walking speeds. Ten healthy males walked overground at three different speeds while FHL fascicle length changes were recorded with ultrasound and muscle activity was recorded with surface electromyography (EMG). Fascicle length at heel strike at toe off and at peak EMG activity did not change with speed. Range of FHL fascicle length change (3.5-4.5 and 1.9-2.9 mm on average in s…
Innervation zone shift at different levels of isometric contraction in the biceps brachii muscle
2007
Experiments were carried out to examine whether innervation zone (IZ) location remains stable at different levels of isometric contraction in the biceps brachii muscle (BB), and to determine how the proximity of the IZ affects common surface electromyography (sEMG) parameters. Twelve subjects performed maximal (MVC) and submaximal voluntary isometric contractions at 10%, 20%, 30%, 40%, 50% and 75% of MVC. sEMG signals were recorded with a 13 rows x 5 columns grid of electrodes from the short head of BB. The IZ shifted in the proximal direction by up to 2.4 cm, depending upon the subject and electrode column. The mean shift of all the columns was 0.6+/-0.4 cm (10% vs. 100% MVC, P0.001). This…
Bowel wall thickening: inquire or not inquire? Our guidelines
2018
Introduction Bowel wall thickening is not an uncommon finding among patient undergoing abdomen CT scan. It may be caused by neoplastic, inflammatory, infectious or ischaemic conditions but also be a normal variant. Although specific radiologic patterns may direct to a precise diagnosis, occasionally misidentification may occur. Thus, in the absence of guidelines, further and not always needed diagnostic procedures (colonoscopy, esophagogastroduodenoscopy or capsule endoscopy) are performed. Patients and methods We conducted a retrospective study on data collected from May 2016 to June 2017. We selected 40 adult patients, admitted in Emergency Department with "abdominal pain" and undergone a…
Effects of treadmill running and fatigue on impact acceleration in distance running
2014
The effects of treadmill running on impact acceleration were examined together with the interaction between running surface and runner's fatigue state. Twenty recreational runners (11 men and 9 women) ran overground and on a treadmill (at 4.0 m/s) before and after a fatigue protocol consisting of a 30-minute run at 85% of individual maximal aerobic speed. Impact accelerations were analysed using two lightweight capacitive uniaxial accelerometers. A two-way repeated-measure analysis of variance showed that, in the pre-fatigue condition, the treadmill running decreased head and tibial peak impact accelerations and impact rates (the rate of change of acceleration), but no significant differenc…
Effect of 3 Weeks Use of Compression Garments on Stride and Impact Shock during a Fatiguing Run
2015
Excessive and prolonged exposure to impact acceleration during running is associated with increased injury rate. Acute use of compressive garments has been speculated to improve attenuation. However, it is unknown how longer interventions of compressive garments influence attenuation in running. 40 runners trained with compressive and placebo stockings for 3 weeks. Perception of comfort, stride parameters (rate, length) and impact acceleration (head and tibial peak acceleration, magnitude, acceleration rate and attenuation) were measured every 5 min during a fatigue run (30 min at 80% of the individual's maximal aerobic speed). Compressive stockings reduced tibial peak acceleration and magn…
Acute effects of transient vertical whole-body vibration
1991
The question as to whether shock-type whole-body vibration causes increasingly acute strain was investigated. Random vibrations were superimposed with shocks differing in amplitude and in number per unit of time in a systematic manner. The weighted root mean square (rms) acceleration was kept constant in all over the varied experiments. A total of 17 men were exposed to vibration from an electrohydraulic simulator. The following strain criteria were used: biodynamic behavior of the trunk and the head, electrical activity of the muscles of the back and the neck, subjective sensation, skin temperature in the lumbar area and visual and tracking performance. It was found that increasing shock a…
Is the V˙o 2 slow component dependent on progressive recruitment of fast-twitch fibers in trained runners?
2001
The goal of this study was to use spectral analysis of EMG data to test the hypothesis that the O2 uptake (V˙o 2) slow component is due to a recruitment of fast fibers. Thirteen runners carried out a treadmill test with a constant speed, corresponding to 95% of the velocity associated with maximal V˙o 2. TheV˙o 2 response was fit with the classical model including three exponential functions. Electrical activity of six lower limb muscles (vastus lateralis, soleus, and gastrocnemius of both sides) was measured using electromyogram surface electrodes. Mean power frequency (MPF) was used to study the kinetics of the electromyogram discharge frequency. Three main results were observed: 1) a co…
Reproducibility of isometric strength: measurement of neck muscles
1999
Abstract Objective. To evaluate the repeatability of an advanced method of measuring the strength of functionally different groups of neck muscles using an isometric apparatus. Design. A repeated measures design was used within and between sessions. Background. Chronic neck pain has been associated with poor isometric neck strength. In rehabilitation, strength measurements may thus help to evaluate the basic condition and show whether or not treatments and exercises have been beneficial for improving strength. Previous tests have concentrated on testing strength while trying to bend forwards and backwards, but no biomechanics device, able to test rotator muscles, has been presented. Method.…
Elderly obese women display the greatest improvement in stair climbing performance after a 3-week body mass reduction program
2004
OBJECTIVE: To depict the general trends of muscle anaerobic performance in obese subjects within a wide range of age and body weight. DESIGN: Cross-sectional study for the measurement of lower limb maximal anaerobic power output with a modification of the Margaria stair climbing test in a large population of obese subjects of both genders within a wide span of age (18-80 y) and body mass index (BMI, 30-68 kg m(-2)). Furthermore, body composition was also determined by bioimpedance analysis in a representative subgroup, in order to evaluate the relationships between fat-free mass (FFM) and power output. SUBJECTS: A total of 1298 obese subjects (486 males, 812 females) from an Italian populat…