Earth is the homeworld of the Human race, located in the Sol System. It is the third planet of the system, orbiting at precisely 1 AU from its parent star, a G2-V Main Sequence star known as Sol, or simply The Sun. Contrary to popular belief, Earth is not the Federation's headquarters - it is Mars.
What causes whole body vibration. Drivers of some mobile machines, including certain tractors, fork lift trucks and quarrying or earth-moving machinery, may be exposed to WBV and shocks, which are associated with back pain.
Calcium causes contraction in skeletal muscle fibers, and magnesium causes relaxation. When there is too much calcium and insufficient magnesium inside a cell, you can get sustained muscle contraction: twitches, spasms, and even convulsions.