I would like to briefly explain my thought process behind a desired repetition range of an exercise/workout program. If you are relatively new to weight training, you may find this helpful.
In your workout routine, for a specific exercise, the program calls for 4 sets of 8 to 10 repetitions. Before you even select a weight, think about what weights you have used for said exercise in the past. Now, in a perfect comfortable world, you should be able to complete 4 sets of 10 repetitions with this weight. But the idea here is to push yourself outside of your comfort zone. The only way to grow is getting to that uncomfortable, challenging place, where you are going to struggle, grit your teeth, bite your tongue, possibly yell out loud and might need help.
My approach is as such… select a weight that starts to get difficult for you around the 6th rep, is very difficult at the 7th rep, and the remaining reps might not even be completed without a spot. Of course you want to complete the number of sets listed in the workout, but you should be challenging yourself, which is what resistance training is all about, right?
If you are a beginner, you might want to hire a trainer to help you understand this concept and to push you accordingly, until you get accustomed to doing it on your own.
Try this mental approach the next time you’re in the gym. Push yourself just a little further than you feel comfortable with… I bet you can complete the task at hand… DO IT!