Many people in the world, especially women, practice body hair removal. When hair is first removed from the legs, the skin is smooth until the hair grows back. The new hairs can be prickly to the touch, especially if the hair has been shaved. Shin stubble refers to the new growth of hair on the front part of the lower leg.
All humans have hairs on their legs, but the amount can vary with each individual person. A woman's hair tends to be lighter and softer than that of a man. In many countries, leg hair removal is the accepted norm, and natural hair growth may not be in fashion. Some men also choose to remove leg hair, especially competitive swimmers. To remove hair, one may choose to shave leg hair, or remove it in another way such as waxing it.
Hair grows in cycles. This means that in the shin area, for example, about 10 percent of the hair follicles, which produce hairs, are dormant. Most of the other hair follicles have hairs actively growing from them. When the hairs grow, they contain a substance called melanin.
Melanin is a pigment, and gives the hair color. The color of leg hair can range from light to dark depending on the individual. A small percentage of the hairs on the leg are not actively growing, and are nearing the time where they will fall out, but basically, the majority of the hair is present on the leg.
When an individual cuts off the hairs close to the root with a blade during shaving, the hair is not completely removed. Simply that portion that is outside of the skin is removed during the process. The majority of the follicle is actively growing, and so the follicle produces more hair as normal. This hair, that grows outward, is the shin stubble.
Shaving razors slice off the hair in a cross-section, leaving a blunt end behind. This blunt end, once the follicle grows it out, feels prickly to the touch, like a man's facial stubble, and so the shin hairs are called shin stubble. Other forms of temporary hair removal, such as waxing, rip the hair out by the root. The follicle then has to grow a new hair and this hair does not have the blunt end of a cut hair, so the new hair growth does not feel as stubbly.
Those who prefer to remove leg hair for cultural reasons may not want to have visible hair growth on their legs, and so shave regularly. Even without obvious visible growth, the short hairs can also feel prickly to the touch. The time between shaving and the development of shin stubble may be reduced if the individual uses a blunt razor, shaves dry skin or doesn't use moisturizer after a shave.