Or is it less repetitions with heavier weights? A common question, indeed. When people first get into strength training, they always struggle with the answer. Women are afraid of getting big, bulky muscles while the men aren't. But either way, both groups share an interest in getting stronger. So should women be using the more-rep method and men the opposite? In all honesty, it really doesn't matter. The point is to fatigue your muscles. So whether you do so in five, ten or twelve repetitions (or somewhere in between)—you'll see strength gains. Check out the following video from the American Council on Exercise. It'll reiterate my thoughts above.
Question: If you strength train, which method are you using?