- Why is warming up before exercise a good idea?
- Why are taking anabolic steroids a dangerous way to try to build up muscles?
Further Reading / Supplemental Links
- http://www.hmc.psu.edu/healthinfo/m/musclestrain.htm
- http://www.cdc.gov/nccdphp/dnpa/physical/everyone/index.htm
- http://en.wiki.org
Vocabulary
aerobic exercises Types of exercises that cause the heart to beat faster and allow the
muscles to obtain energy to contract by using oxygen.
anabolic steroids Hormones that cause the body to build up more protein in its cells.
anaerobic exercise Types of exercises that involve short bursts of high-intensity activity;
forces the muscles to obtain energy to contract without using oxygen.
cardiac muscle An involuntary and specialized kind of muscle found only in the heart.
contraction Shortening of muscle fibers.
extensor The muscle that contracts to cause a joint to straighten.
flexibility exercises Stretching exercises that improve the range of motion of muscles and
joints.
flexor The muscle that contracts to cause a joint to bend.
involuntary muscle A muscle that a person cannot consciously control; cardiac muscle
and smooth muscle are involuntary.
muscle cells Long, thin cells that can contract; also called muscle fibers.
muscle fibers Long, thin cells that can contract; also called muscle cells.
muscular endurance The ability of a muscle to continue to contract over a long time
without getting tired.