Search results for "dynamometer"
showing 10 items of 53 documents
Do Stretch Durations Affect Muscle Mechanical and Neurophysiological Properties?
2016
International audience; The aim of the study was to determine whether stretching durations influence acute changes of mechanical and neurophysiological properties of plantar flexor muscles. Plantar flexors of 10 active males were stretched in passive conditions on an isokinetic dynamometer. Different durations of static stretching were tested in 5 randomly ordered experimental trials (1, 2, 3, 4 and 10×30-s). Fascicle stiffness index, evoked contractile properties and spinal excitability (Hmax/Mmax) were examined before (PRE), immediately after (POST0) and 5 min after (POST5) stretching. No stretch duration effect was recorded for any variable. Moreover, whatever the stretching duration, st…
Muscle deficits persist after unilateral knee replacement and have implications for rehabilitation.
2009
BackgroundKnee joint arthritis causes pain, decreased range of motion, and mobility limitation. Knee replacement reduces pain effectively. However, people with knee replacement have decreases in muscle strength (“force-generating capacity”) of the involved leg and difficulties with walking and other physical activities.Objective and DesignThe aim of this cross-sectional study was to determine the extent of deficits in knee extensor and flexor muscle torque and power (ability to perform work over time) and in the extensor muscle cross-sectional area (CSA) after knee joint replacement. In addition, the association of lower-leg muscle deficits with mobility limitations was investigated.Methods…
Effects of ageing on motor unit activation patterns and reflex sensitivity in dynamic movements.
2009
Both contraction type and ageing may cause changes in H-reflex excitability. H reflex is partly affected by presynaptic inhibition that may also be an important factor in the control of MU activation. The purpose of the study was to examine age related changes in H-reflex excitability and motor unit activation patterns in dynamic and in isometric contractions. Ten younger (YOUNG) and 13 elderly (OLD) males performed isometric (ISO), concentric (CON) and eccentric (ECC) plantarflexions with submaximal activation levels (20% and 40% of maximal soleus surface EMG). Intramuscular EMG data was analyzed utilizing an intramuscular spike amplitude frequency histogram method. Average H/M ratio was a…
Neuromuscular Responses to 14 Weeks of Traditional and Daily Undulating Resistance Training
2015
This study compared traditional (TP) and daily undulating (DUP) periodization on muscle strength, EMG-estimated neural drive and muscle architecture of the quadriceps femoris (QF). 10 non-athletic females (24.4±3.2 years) performed 14 weeks of isometric training for the QF exercising 1 leg using TP and the contralateral leg using DUP. Intensities varied from 60% to 80% of MVC and the intensity zones and training volume were equated for each leg. Knee extension MVC, maximal voluntary QF-EMG activity and vastus lateralis (VL) muscle architecture were measured in both legs before, after 6 weeks and after 14 weeks of training using dynamometry, surface EMG and ultrasonography. Isometric MVC and…
The early changes in trunk muscle strength and disability following lumbar spine fusion
2012
To analyze trunk muscle function pre- and postoperatively in patients undergoing lumbar spine fusion. Associations between changes in trunk muscle strength and disability were also studied.A total of 114 patients undergoing lumbar spine fusion participated in the study. The flexion and extension strength of the trunk was measured preoperatively and 3 months after surgery using a strain-gauge dynamometer. Disability and pain during the past week was evaluated with the Oswestry disability index (ODI) and visual analog scale (VAS), respectively.Preoperative trunk extension and flexion strength levels were 319 N and 436 N in males, respectively, and 160 N and 214 N in females, respectively. In …
Neuromuscular adaptations to constant vs. variable resistance training in older men.
2013
This study examined the effects of constant or variable external resistance training on neuromuscular adaptations in the lower limbs of older men. 37 subjects (age 65±4 year) were quasi-randomly assigned to the constant or variable training group, or a non-training control group. Training consisted of a 20-week medium-intensity, high volume resistance training program. Maximum bilateral concentric and isometric force production of the leg extensors as well as repetitions-to-failure test were performed pre-, mid- and post-training. Vastus lateralis muscle cross-sectional area was assessed by ultrasound and lean leg mass was assessed by dual-energy x-ray absorptiometry. Both training groups s…
Muscular Strength Imbalances Are not Associated with Skin Temperature Asymmetries in Soccer Players
2020
Although strength imbalances using isokinetic dynamometer have been examined for injury risk screening in soccer players, it is very expensive and time-consuming, making the evaluation of new methods appealing. The aim of the study was to analyze the agreement between muscular strength imbalances and skin temperature bilateral asymmetries as well as skin temperature differences in the hamstrings and quadriceps. The skin temperature of the anterior and posterior thigh of 59 healthy male soccer athletes was assessed at baseline using infrared thermography for the identification of hamstrings-quadriceps skin temperature differences and thermal asymmetries (>
Diurnal Rhythm of the Muscular Performance of Elbow Flexors During Isometric Contractions
1996
The influence of time of day on elbow flexion torque was studied. Thirteen physical education students, 7 males and 6 females, made maximal and submaximal isometric contractions at 90 degrees of elbow flexors using a dynamometer. The torque developed was measured on each contraction. The myoelectric activity of the biceps muscle was also measured at the same time by surface electromyography (EMG) and quantified from the root mean square (RMS) activity. Torque and surface EMGs were measured at 6:00, 9:00, 12:00, 15:00, 18:00, 21:00, and 24:00 h over the same day. Oral temperature before each test session was measured on each occasion after a 30-min rest period. We observed a diurnal rhythm i…
Compression tests of cv. Nocellara del Belice table olives for texture evaluation during storage
2014
The influence of pasteurization temperature and time of treatment on the flesh firmness and the evolution of microbial communities was studied for table olives Cv. Nocellara del Belice, packed in glass jars and processed with a tunnel pasteurizer. Pasteurization at industrial scale was carried out within a tunnel pasteurizer applying the treatment at 75 °C for 8 min in the thermal center of the jars. Besides flesh firmness and microbial evolutions, pH, total ti-tratable acidity (TTA) and colour were evaluated for the table olives during storage at 6, 12 and 15 months from packing. Table olives showed a high stability and an acceptable flesh firmness for the entire period under observation. …
Midlife muscle strength and human longevity up to age 100 years: a 44-year prospective study among a decedent cohort
2011
We studied prospectively the midlife handgrip strength, living habits, and parents’ longevity as predictors of length of life up to becoming a centenarian. The participants were 2,239 men from the Honolulu Heart Program/Honolulu–Asia Aging Study who were born before the end of June 1909 and who took part in baseline physical assessment in 1965–1968, when they were 56–68 years old. Deaths were followed until the end of June 2009 for 44 years with complete ascertainment. Longevity was categorized as centenarian (≥100 years, n = 47), nonagenarian (90–99 years, n = 545), octogenarian (80–89 years, n = 847), and ≤79 years (n = 801, reference). The average survival after baseline was 20.8 years (…