well i want muscle that i can maintain my speed....i have little muscle but i need alittle more but idk how to build muscle to maintain my speed and my power
speed = fitness. run. do sprints. run a lot. that's mainly speed. you need to tone yourself, not bulk yourself. muscles will give strength - but again, too much muscle results in lack of flexibility. easily leads to pulled muscles and such if you have too much muscle because its so much more stress on them to relax and contract constantly .. you want strong, flexible muscles, and maybe if you are thin like a toothpick you want some more muscle mass to make you sturdy, but if you are "normal" you need to get stronger and more importantly fitter. just don't overdo the muscle bulking up training. things like pushups and and daily running are enough to strengthen your arms and legs as much as you need, if you still feel you need more muscle then weight training and a proper diet helps.
from what i know, speed is not dependent on muscle at all (leg muscles yeah, but that's a given - again, strong muscles is what I mean - ask one of those body builders to run here and there, they'll probably cramp up like crazy).
power comes from proper technique, proper timing (see justine henin - 5 foot 4) and yes if you do need enough mass and torso strength to drive through and sometimes muscle through balls. again, to start off (i have no idea how much physical stuff you get done..) 15 minutes run a day for stamina (and if you are serious 5 minute sprints to get faster), and basic exercises, like stretching, pushups, curls etc etc for like 15 minutes is a very modest but incredible start to get fitter and stronger. for gaining pure muscle i think you pretty much have to eat protein and work out.