Sometimes when your calcium/magnesium ratio is off, you can get twitching. I get one in my diaphram that feels like a fish flopping in my chest. If you are low in calcium intake, or very low in magnesium, the muscles do a dance of sorts. So you could try to balance that out.
(February 2017) A concrete slab is a common structural element of modern buildings. Horizontal slabs of steel reinforced concrete, typically between 4 and 20 inches (100 and 500 millimeters) thick, are most often used to construct floors and ceilings, while thinner slabs are also used for exterior paving.
Section 402.2.8, Slab-on-grade floors. Slab insulation requirements: CZ 1-3: R-0; CZ 4-5: R-10, 2 ft; CZ 6-8: R-10, 4 ft. R-5 must be added to the requirement for heated slabs. The insulation depth is to the depth of the footing or 2 feet, whichever is less in Climate Zones 1-3 (for heated slabs).