molecule. 1  Chemistry, Physics. the smallest physical unit of an element or compound, consisting of one or more like atoms in an element and two or more different atoms in a compound. 2  Chemistry. a quantity of a substance, the weight of which, measured in any chosen unit, is numerically equal to the molecular weight; gram molecule.
When I do crunches my neck starts to tighten up and it makes me have to rest before doing another set of crunches.
Try an ice pack to soothe your neck. Cold dulls local pain and limits the buildup of lactic acid, which can cause soreness. Use an ice pack and place it on the part of your neck that feels stiff (usually the back of your neck at your hairline).Hold the pack there for 10-15 minutes every 2 hours. 1  You can also try a more comfortable position to ice your neck. 2  Sit in a comfortable chair and rest your head back.ry an ice pack to soothe your neck. Cold dulls local pain and limits the buildup of lactic acid, which can cause soreness. Use an ice pack and place it on the part of your neck that feels stiff (usually the back of your neck at your hairline).