Search for dissertations about: "maximal voluntary force"

Showing result 1 - 5 of 17 swedish dissertations containing the words maximal voluntary force.

2. 1. Identification of single motor units in ultrafast ultrasound image sequences of voluntary skeletal muscle contractions

   Author : Robin Rohlén; Christer Grönlund; Jun Yu; Dario Farina; Umeå universitet; []
   Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ultrafast ultrasound; motor units; decomposition; skeletal muscle; voluntary contractions; electromyography; twitch; imaging;

   Abstract : The central nervous system controls human force production by successive recruitment of motor units in the skeletal muscles and changing their neural firing rate. The motor unit comprises a motoneuron, its innervated muscle fibers, and its axons. READ MORE

4. 2. Lumbar muscle fatigue and recovery : evaluation of electromyography in patients with long-term low-back pain and in healthy subjects

   Author : Britt Elfving; Karolinska Institutet; Karolinska Institutet; []
   Keywords : Disability; electromyography; exponential; force level; gender; healthy subjects; interelectrode distance; low-back pain; erector spinae; maximal voluntary contraction; muscle fatigue; recovery; reliability; validity.;

   Abstract : Background: Lumbar muscle function is considered to be an important component of longterm low- back pain. The change in the median frequency of the power spectrum of the electromyographic (EMG) signal is commonly used to estimate muscle fatigue. READ MORE

5. 3. Effects of unloading on skeletal muscle mass and function in man

   Author : Hans Berg; Karolinska Institutet; Karolinska Institutet; []
   Keywords : Atrophy; bedrest; concentric and isometric and eccentric muscle actions; disuse; electromyography; fatigue; fiber types and size; humans; inactivity; maximal voluntary force; recovery; skeletal muscle cross-sectional area; strength; suspension; tomog;

   Abstract : An experimental human model of skeletal muscle unloading of one lower limb and confined bedrest were employed to quantitate the adaptive responses to 10 days, 4 or 6 wk of unloading in healthy humans on quadricep skeletal muscle mass and function. Muscle cross-sectional area (CSA) was assessed using tomographic imaging (CT, MRI). READ MORE

6. 4. Quantification of skeletal, muscular and kinematics parameters in scoliosis : methodological and clinical studies

   Author : Khaled Mohamed Diab; Karolinska Institutet; Karolinska Institutet; []
   Keywords : Idiopathic scoliosis; new methods; scoliotic angle; vertebral body volume; intercostal muscle; ultrasonography; ground reaction force; centre of mass; centre of pressure; motor control;

   Abstract : This dissertation presents new methods derived for precise evaluation of a number of anatomical and functional variables of the complex thoracospinal deformity in scoliosis. By consensus the scoliotic angle at the frontal plane is measured on radiographs using the Cobb method. READ MORE

7. 5. Acute and early chronic responses to resistance exercise using flywheel or weights

   Author : Lena Norrbrand; Per Tesch; Ola Eiken; Per Aagaard; Mittuniversitetet; []
   Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; electromyography; flywheel; magnetic resonance imaging; resistance exercise; Sports; Idrott;

   Abstract : Resistance exercise using weights typically offers constant external load during coupled shortening (concentric) and lengthening (eccentric) muscle actions in sets of consecutive repetitions until failure. However, the constant external load and the inherent capability of skeletal muscle to produce greater force in the eccentric compared with the concentric action, would infer that most actions are executed with incomplete motor unit involvement. READ MORE