Sökning: "shortening velocity"

Visar resultat 16 - 20 av 27 avhandlingar innehållade orden shortening velocity.

1. 16. Effects of unloading on skeletal muscle mass and function in man

   Författare :Hans Berg; Karolinska Institutet; Karolinska Institutet; []
   Nyckelord :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;

   Sammanfattning : 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). LÄS MER

3. 17. Intracellular mechanisms of skeletal muscle fatigue : role of creatine kinase

   Författare :Anders Dahlstedt; Karolinska Institutet; Karolinska Institutet; []
   Nyckelord :Skeletal muscle fatigue; creatine kinase; inorganic phosphate; adenosine diphosphate;

   Sammanfattning : During intense physical activity the maximal power output of skeletal muscles is reduced, a condition described as muscle fatigue. The cause of impaired muscle function seen in fatigue is multifactorial. LÄS MER

4. 18. A novel single skeletal muscle cell in vitro motility assay : effects of aging and non-enzymatic glycosylation on myosin function

   Författare :Peter Höök; Karolinska Institutet; Karolinska Institutet; []
   Nyckelord :In vitro motility; motility speed; aging; single muscle fiber; myosin isoform; temperature; scaling; glycation;

   Sammanfattning : The aims of this study were to develop a single skeletal muscle fiber in vitro motility assay, and to employ the assay in order to study the effects of aging and non-enzymatic glycosylation on the mechanical properties of the motor protein myosin in an attempt to improve our understanding of the molecular mechanisms underlying the aging-related impairment in regulation of muscle function. Myosin was extracted from a millimeter short single muscle fiber segment directly onto a nitrocellulosecoated coverslip for subsequent analyses of the functional properties of the motor protein. LÄS MER

5. 19. Effects of Ageing and Physical Activity on Regulation of Muscle Contraction

   Författare :Alexander Cristea; Lars Larsson; Anna-Stina Höglund; Ingrid Lundberg; Uppsala universitet; []
   Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; ageing; sarcopenia; sprint training; progressive resistance training; in vivo function; isokinetic dynamometer; in vitro function; single permeabilised fibre; myonuclear domain; confocal microscopy; Medicine; Medicin;

   Sammanfattning : The aims of this study were to investigate the mechanisms underlying (1) the ageing-related motor handicap at the whole muscle, cellular, contractile protein and myonuclear levels; and (2) ageing-related differences in muscle adaptability.In vivo muscles function was studied in the knee extensors. LÄS MER

7. 20. Context dependent adaptation of biting behavior in human

   Författare :Anders Johansson; Benoni Edin; Karl-Gunnar Westberg; Peter Svensson; Umeå universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; EMG; bite force; human; mastication; muscles; jaw opening reflex; motor control; reflex modulation; periodontal attachment loss; periodontitis; fysiologi; Physiology;

   Sammanfattning : The focus of this thesis was to study an action that humans perform regularly, namely, to hold a morsel between the teeth and split it into smaller pieces. Three different issues related to this biting behavior were addressed:  (1) the effect of redu­c­ed perio­dontal tissues on food holding and splitting behavior; (2) the behavioral conse­quences of performing different bite tasks with different functional requirements, i. LÄS MER