Magnesium and potassium, along with sodium and calcium, are examples of electrolytes that are present in the blood. Electrolytes help trigger and regulate electrical impulses in the heart and low levels of magnesium and potassium can lead to an electrolyte imbalance, which can contribute to arrhythmia.
Passing hard stools is usually as a result of constipation or the infrequent movement of the bowels. Most healthy people have at least three bowel movements per week, according to MedlinePlus. If you are unable to have a bowel movement or are having difficulty passing stool, contact your doctor.
Normal stool consistency is firm but soft. The moisture content in stool has to be sufficient to ensure that the stool remains soft but not watery and unable to retain its form. However, as the water content in stool decreases, it becomes dry and hard. As a a result passing stool can be difficult and even painful.