Exclusively breastfed babies do not require additional water even when it is very hot outside, as long as baby is allowed to nurse as needed. Even in extremely hot, dry weather your baby can get all the liquids needed via breastmilk.
Smooth muscles contract very slowly, whereas skeletal muscles can contract at different rates. Skeletal muscles can be composed of fast-contracting fibers, slow-contracting fibers or a mixture of both.
The muscles are of three major types known as smooth, skeletal, and cardiac. Out of those three, skeletal muscles are mostly known, cardiac muscles are also known up to a fair extent, but the most common type of smooth are not well known. It would be interesting to explore the characteristics and differences between mostly known and mostly unknown types of muscles.