Search results for "knee"
showing 10 items of 527 documents
The effects of the Nordic hamstring exercise on sprint performance and eccentric knee flexor strength: A systematic review and meta-analysis of inter…
2021
Objectives: The primary aim of this study was to investigate the effects of the Nordic hamstring exercise (NHE) on sprint performance (i.e., 5, 10 and 20 m) and explore associations between study characteristics and sprint outcomes in team sport players. Secondary aims were to (1) investigate the effects of the NHE on eccentric strength of the knee flexors (ESKF) with categorical subgroup analysis to determine differences between recreationally, well-trained individuals and young athletes, (2) determine the relation between ESKF and sprint performance in team sport players, and (3) explore the effect of study characteristics (i.e., weekly volume, time duration and body mass) on ESKF.Methods…
MOTOR DYSFUNCTION OF THE "NON AFFECTED" LOWER LIMB: A KINEMATIC COMPARATIVE STUDY BETWEEN HEMIPARETIC STROKE AND TOTAL KNEE PROSTHESIZED PATIENTS
2009
In patients with hemispheric stroke, abnormal motor performances are described also in the ipsilateral limbs. They may be due to a cortical reorganization in the unaffected hemisphere; moreover, also peripheral mechanisms may play a role. To explore this hypothesis, we studied motor performances in 15 patients with hemispheric stroke and in 14 patients with total knee arthroplasty, which have a reduced motility in the prosthesized leg. Using the unaffected leg, they performed five superimposed circular trajectories in a prefixed pathway on a computerized footboard, while looking at a marker on the computer screen. The average trace error was significantly different between the groups of pat…
Effect of total knee replacement surgery and postoperative 12 month home exercise program on gait parameters
2017
Abstract Objective To evaluate the effects of surgery and a postoperative progressive home exercise program on gait parameters among individuals operated with total knee arthroplasty. Design Single blinded randomized controlled trial. Subjects 108 patients (84 females, 24 males, mean age 69 years). Interventions Patients were equally randomized into an exercise group (EG) and control group (CG). The 12-months progressive home exercise program starting two months postoperatively was compared to usual care. Methods Gait analysis was performed using the Gaitrite electronic walkway system. In addition, knee extension and flexion strength were measured by a dynamometer preoperatively, and pain o…
Use of accelerometers and gyros for hip and knee angle estimation
2013
In this paper a wearable sensor system, consisting of accelerometers and gyros, has been studied to estimate hip and knee angles. The proposed algorithm, developed in order to avoid the error accumulation due to gyroscopes drift, has been tested on angle measurement of the hip and knee of a commercial device for assisted gait. The results have shown a good accuracy of the angles estimation, also in high angle rate movement
Effect of time-of-day-specific strength training on serum hormone concentrations and isometric strength in men.
2007
A time-of-day influence on the neuromuscular response to strength training has been previously reported. However, no scientific study has examined the influence of the time of day when strength training is performed on hormonal adaptations. Therefore, the primary purpose of this study was to examine the effects of time-of-day-specific strength training on resting serum concentrations and diurnal patterns of testosterone (T) and cortisol (CORT) as well as maximum isometric strength of knee extensors. Thirty eight diurnally active healthy, previously untrained men (age 20-45 yrs) underwent a ten-week preparatory strength training period when sessions were conducted between 17:00-19:00 h. Ther…
The association between muscle EMG and perfusion in knee extensor muscles
2006
The relationships between electromyographic (EMG) activity and force as well as muscle blood flow and work have been well established. However, the association between muscle blood flow and EMG activity remains unsolved. Thus, to test the hypothesis that muscle EMG activity relates to muscle perfusion in different compartments of the quadriceps femoris (QF) muscle, 12 healthy male subjects were studied. During two very submaximal exercise bouts, at different exercise intensities, oxygen labelled radiowater and positron emission tomography were used to measure muscle perfusion. In addition, produced force of knee extensors and muscle EMG activity in the vastus lateralis (VL), vastus medialis…
Neuromuscular Fatigue Following Isometric Contractions with Similar Torque Time Integral
2014
International audience; Torque time integral (TTI) is the combination of intensity and duration of a contraction. The aim of this study was to compare neuromuscular alterations following different isometric sub-maximal contractions of the knee extensor muscles but with similar TTI. Sixteen participants performed 3 sustained contractions at different intensities (25 %, 50 %, and 75 % of Maximal Voluntary Contraction (MVC) torque) with different durations (68.5 +/- 33.4 s, 35.1 +/- 16.8 s and 24.8 +/- 12.9 s, respectively) but similar TTI value. MVC torque, maximal voluntary activation level (VAL), M-wave characteristics and potentiated doublet amplitude were assessed before and immediately a…
The Role of Vitamin D in Early Knee Osteoarthritis and Its Relationship with Their Physical and Psychological Status
2021
Osteoarthritis (OA) is a common joint condition and one of the greatest causes of disability worldwide. The role of vitamin D in the origin and development of the disease is not clear, although it could have important implications for diagnosis and treatment. For this proposal, a cross-sectional study with a non-probabilistic sample was performed. In total, 48 with early osteoarthritis (EOA) and 48 matched controls were selected, and serum 25(OH)D and parathyroid hormone (PTH) levels were analyzed. In addition, physical and psychological variables were measured to establish their relationship with vitamin D levels. Patients with EOA showed lower levels (22.3 ± 7.3 ng/mL) in comparison to ma…
Effect of combined electrostimulation and plyometric training on vertical jump height.
2002
This study investigated the influence of a 4-wk combined electromyostimulation (EMS) and plyometric training program on the vertical jump performance of 10 volleyball players.Training sessions were carried out three times weekly. Each session consisted of three main parts: EMS of the knee extensor muscles (48 contractions), EMS of the plantar flexor muscles (30 contractions), and 50 plyometric jumps. Subjects were tested before (week 0), during (week 2), and after the training program (week 4), as well as once more after 2 wk of normal volleyball training (week 6). Different vertical jumps were carried out, as well as maximal voluntary contraction (MVC) of the knee extensor and plantar flex…
Zur erweitrten Indikationsstellung der Herbert-Schrauben-Osteosynthese
1995
Since 1984 the typical headless double threaded Herbert/Whipple screw is known in managing scaphoid fractures and scaphoid non-unions. We resume technical, biomechanical and histological aspects to point out advantages and disadvantages of this osteosynthesis. Our case review of 39 patients illustrate the same good results as achieved in treating scaphoid injuries, when using the Herbert/Whipple screw of a larger diameter for expanded indications other than scaphoid fractures, such as humeral- or radial-head fractures, Jones fractures and others.