So, I started going to the gym about a month ago. Doing dumbell curls I started at 10lbs. I tried 50lbs at first.
Mistake!
Sized down until I got to 10lbs. I was looking for the first one I could do 20 reps. Then, as days went on, I kept moving up sizes. I’m currently at 25lbs. I keep wanting to move up to 30lbs, but my body gives way around the 12-15 rep range. So, not quite there yet. But the first 10 reps of 25lbs aren’t even hard anymore. It only gets increasingly more difficult after the 10 mark, but more often than not the 15 mark. 15-20 are the hard ones.
But with 30lbs it’s hard right from the start.
So, should I be doing the 30lbs reps, even if its less than 20 reps? Or do the 25lbs reps which I can easily do 3/4ths of before it becomes a struggle for the last few reps?
No. It’s not bad. You’ll grow muscle. There is an upper limit for productivity. It won’t be as good for developing pure strength. It takes longer. It can be good for rehabilitating an injury, targeting a specific muscle, or managing fatigue.
You should target 2-3 reps in reserve. That means 2-3 reps before you literally cannot lift the weight.
If you’re doing sets of 20, it will be very difficult to injure yourself.