What is a good weight to start off with dumbbells? My grandparents have two that are one lb. And they told me if I do a lot of reps with them it will help with my arms but I don't feel like one pound will do much. Any help is appreciated.
Well some of the muscle freaks at the la fitness make fun of me for lifting just the bar when doing bench press (I'll lift it 100-150 times) but then after talking to them I get them to wrestle with me and they find out really quick who is stronger... some people want to be able to pick up and move a whole truck 3 feet, others (me) want to take it apart and move it miles.
Muscle endurance is more powerful than muscle strength.
So to answer yes lifting lighter weight and doing a lot of reps will make you stronger.