To protect them from ultraviolet rays from the sun.
<span>Maggie's training regimen may put her at risk to develop secondary amenorrhea. While amenorrhea is the absence of menstruation, secondary amenorrhea is the absence of the menstrual cycle in females who have started menstruating (having had at least one cycle) and then stop menstruating for a period longer than three months. Secondary amenorrhea occurs in times of extreme stress or weight loss (such as anorexia). Female soldiers have experienced secondary amenorrhea when they have gone to war or have become prisoners of war. Hormone shots, extreme weight gain, birth control, and certain medications also cause the condition.</span>
Peristalsis is a series of wave-like muscle contractions that move food through the digestive tract. It starts in the esophagus where strong wave-like motions of the smooth muscle move balls of swallowed food to the stomach.
