muscles and fat
 

i have really flabby arms and i have joined weight training for almost a month. the problem is, i want my arm to be lean and slim, not the same size only with muscles.
so, if i continue with weight training, without diet, will my arms stay the same size + muscles???

no they'll probably get bigger the fat will stay there and you might build up muscle under the fat making them bigger. remember you cannot spot reduce fat i.e if you work you arms constantly you wont burn fat there it'll come from all over the body

As Si has said you really do have to do both to get the results you want, and for the reasons he gave.

Don't worry too much about getting everything right in one go though. Stick with your exercise and slowly add in other forms of activity, to give you the best health and fitness benefits. Remember the most important thing about doing exercise is that you enjoy it and are motivated to keep at it regularly.

When you feel as though you have enough knowledge, control and enjoyment from your exercise then think about adding in some small dietary restrictions, like one slice of bread less a day. Replacing butter in sandwiches with mustard or salsa. Always eating breakfast. Reducing the amount of processed foods in your daily diet.

None of the 'diet' stuff really needs you to count calories if you really don't want to. Just make small, sensible and attainable changes - forever!

Good luck