YOUR HEALTH AND WELLNESS
MUSCLE/BUILDING MUSCLE– UNDERSTANDING MUSCLE — OBESITY
Muscle is a soft tissue found in most animals. Muscle cells contain protein filaments of actin and myosin that slide past one another, producing a contraction that changes both the length and the shape of the cell.
Muscles function to produce force and motion. They are primarily responsible for maintaining and changing posture, locomotion, as well as movements of internal organs, such as the contraction of the heart and the movement of food through the digestive system via peristalsis.
Muscle tissues are derived from the mesodermal layer of embryonic germ cells in a process known as myogenesis. There are three types of muscle, skeletal or striated, cardiac, and smooth.
Muscle action can be classified as being either voluntary or involuntary. Cardiac and smooth muscles contract without conscious thought and are termed involuntary, whereas the skeletal muscles contract upon command.
 Skeletal muscles in turn can be divided into fast and slow-twitch fibers.
Muscles are predominantly powered by the oxidation of fats and carbohydrates, but anaerobic chemical reactions are also used, particularly by fast-twitch fibers.
These chemical reactions produce adenosine triphosphate (ATP) molecules that are used to power the movement of the myosin heads.
The term muscle is derived from the Latin musculus meaning “little mouse” perhaps because of the shape.
Obesity is a medical condition in which excess body fat has accumulated to an extent that it may have a negative effect on health.
 People are generally considered obese when their body mass index (BMI), a measurement obtained by dividing a person’s weight by the square of the person’s height, is over 30 kg/m2; the range 25–30 kg/m2 is defined as overweight.
 Some East Asian countries use lower values. Obesity increases the likelihood of various diseases and conditions, particularly cardiovascular diseases, type 2 diabetes, obstructive sleep apnea, certain types of cancer, osteoarthritis, and depression.
Proteins are large biomolecules, or macromolecules, consisting of one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalyzing metabolic reactions, DNA replication, responding to stimuli, providing structure to cells, and organisms, and transporting molecules from one location to another.
Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific three-dimensional structure that determines its activity.