Skeletal muscle is composed of bundles of individual muscle fibers and has unique properties which allow it to respond to stimuli by contracting. Individual muscle fibers respond to a stimulus (e.g., nerve impulse) with an all or none response, meaning the muscle fiber contracts to its maximum potential or not at all. Once a muscle has contracted, relaxation must occur before it can contract again. There are three basic types of muscle fibers: slow fibers, fast fibers, and intermediate fibers. Fast fibers contract quickly but for a relatively short duration. Slow fibers respond less rapidly, but are capable of a more sustained contraction. The strength of contraction of a whole muscle is dependent on the number of muscle fibers involved.
In this experiment, you will
- Obtain graphical representation of the force exerted by your hand while gripping.
- Observe the change in hand strength during a continuous grip over time.
- Observe the change in hand strength during rapid, repetitive gripping.