Now that you've read the benefits of strength training, hopefully you've decided to incorporate lifting weights into your workout, if you don't already.
Don't just assume that you should use an eight pound dumbbell for everything you do just because that is what every other woman at the gym does. Instead take the time to figure out how much you should be lifting with these guidelines: Pick a weight that you can lift 10-12 times without straining. Whichever muscle you are working should feel tired (but not exhausted) upon your final rep of the first set. If you can't get past rep number nine, you've gone too heavy. However, you also don't want to feel like you're not working out at all. So if the muscle you're working doesn't feel tired upon rep number 15, then you've gone too light.
Fit's Tip: As you lift your muscles will get stronger; this is the goal right? So in order to get the most of your strength training time, be sure to raise the weight as you get stronger.