[911_993_911]

Since you pretty much have to lift weights until exhaustion (until you can't complete the motion properly anymore from fatigue) to gain strength from them (which I'm assuming you're doing)... and you're lifting enough weight to get tired after only 3 reps, you are probably building muscle mass. As I understand it, 3-5 reps to exhaustion is good for building muscle mass (gettin' big, as it were...though if you're female you won't get as big as males do). 8-12 reps is a good median for a combination of *some* muscle size and muscle tone/endurance. 15-20 reps are excellent for building tone and endurance (firming up more than gaining mass). When you can do your desired number of reps without tiring, obviously you increase the weight.

Increasing the number of sets adds intensity to the workout. (And you should be getting exhausted at the end of your final set.)

(Yes, doing large numbers of reps with low weights without muscle exhaustion has some benefits too, but in order to build new muscle you have to stress it to the point of exhaustion...in essence you "injure" your muscle so that your body "repairs" it and makes it stronger. Fortunately, after a week or so of weight training in this manner, you stop being sore from it.)

Hope this helps,
unc_horse (who took a class in weight training...now just needs to actually go do it again) :wink: