skeletal strength

Examples of skeletal strength in the following topics:

• Force of Muscle Contraction

  • These two fundamental properties limit many key biomechanical properties, including running speed, strength, and jumping distance.
  • Skeletal muscles are attached to bones via tendons that maintain the muscle under a constant level of stretch called the resting length.
  • Simply put,  the tension generated in skeletal muscle is a function of the magnitude of overlap between actin and myosin myofilaments.

• Myocardial Thickness and Function

  • The thickness of the myocardium determines the strength of the heart's ability to pump blood.
  • The structure of cardiac muscle shares some characteristics with skeletal muscle, but has many distinctive features of its own.
  • Cardiomyocytes are shorter than skeletal myocytes and have fewer nuclei.
  • Cardiac muscle, like skeletal muscle, is comprised of sarcomeres, the basic, contractile units of muscle.
  • Cardiac muscle  and skeletal muscle both contain the protein myoglobin, which stores oxygen.

• Arrangement of Fascicles

  • Skeletal muscles are grouped into fascicles, which are bunches of muscle fibers surrounded by a perimysium.
  • Beneath the fascia in skeletal muscle is another layer of connective tissue termed the epimysium which is closely associated with the fascia.
  • The organization of connective tissue throughout and around a muscle provides strength and flexibility while distributing the force evenly.
  • Whilst both cardiac and smooth muscles are also wrapped in connective tissue, they are not differentiated in the same way as skeletal muscles.
  • Skeletal muscle is surrounded by a thick outer layer of connective tissue termed the fascia.

• Interactions of Skeletal Muscles

  • Skeletal muscles interact to produce movements by way of anatomical positioning and the coordinated summation of innervation signals.
  • Skeletal muscle contractions can be grouped based on the length and frequency of contraction.
  • As the strength of the signal increases, more (and larger) motor units are excited.
  • The largest motor units have as much as 50 times the contractile strength as the smaller ones; thus, as more and larger motor units are activated, the force of muscle contraction becomes progressively stronger.
  • Explain the summation interactions of skeletal muscles and how they affect movement

• Abnormal Contractions of Skeletal Muscle

  • A spasm may lead to muscle strains or tears of tendons and ligaments, if the force of the spasm exceeds the tensile strength of the underlying connective tissues, such as with a particularly forceful spasm, or in the case of weakened connective tissues.

• Proprioceptive Sensations

  • Proprioception is the sense of the relative position of neighboring parts of the body and the strength of effort being employed in movement.
  • The Golgi organ (also called Golgi tendon organ, tendon organ, neurotendinous organ or neurotendinous spindle) is a proprioceptive sensory receptor organ that is located at the insertion of skeletal muscle fibers onto the tendons of skeletal muscle.
  • In a Golgi tendon reflex, skeletal muscle contraction causes the agonist muscle to simultaneously lengthen and relax.

• Types of Muscle Tissue

  • There are three kinds of muscle tissue: skeletal, smooth, and cardiac.
  • Skeletal muscles are highly organized with cells lying parallel to each other.
  • Skeletal muscle fibers are the longest muscle fibers and have stripes on their surface.
  • Skeletal muscle is striated, multinucleate, and involuntary.
  • Cardiac muscle is striated, similar to skeletal muscle, but beats involuntarily.

• Aerobic Training vs. Strength Training

  • Skeletal muscle can thus be broken down into two broad categories: Type I and Type II.
  • A number of studies have examined the health benefits of aerobic and/or strength training in improving health and treating health issues.
  • By increasing muscular strength and improving balance, weight training can reduce falls by elderly persons as well.
  • For many people in rehabilitation or with an acquired disability, such as following stroke or orthopaedic surgery, strength training for weak muscles is a key factor to optimize recovery.
  • For people with such a health condition, their strength training is likely to need to be designed by an appropriate health professional, such as a physiotherapist.One side-effect of any intense exercise is increased levels of dopamine, serotonin, and norepinephrine, neurotransmitters that can help to improve mood and counter feelings of depression.

• Characteristics of Muscle Tissue

  • The three types of muscle tissue are skeletal, smooth, and cardiac.
  • Skeletal muscle mainly attaches to the skeletal system via tendons to maintain posture and control movement for example contraction of the biceps muscle, attached to the scapula and radius, will raise the forearm.
  • Cardiac and skeletal muscle are both striated in appearance, while smooth muscle is not.
  • Both cardiac and smooth muscle are involuntary while skeletal muscle is voluntary.
  • Differentiate among the structure and location of skeletal, smooth, and cardiac muscles

• Structure and Function of the Muscular System

  • The muscular system is closely associated with the skeletal system in facilitating movement.
  • Skeletal muscle mainly attaches to the skeletal system via tendons to maintain posture and control movement.
  • Morphologically skeletal myocytes are elongated and tubular and appear striated with multiple peripheral nuclei.
  • Cardiac myocytes are shorter than skeletal equivalents and contain only one or two centrally located nuclei.
  • Skeletal muscle of the muscular system is closely associated with the skeletal system and acts to maintain posture and control voluntary movement.