strength plateau

I started lifting weights on Nautilus machines about 7 months ago. For the few 4 months or so, it was great. I was getting continously stronger and adding weights and repetitions. After that, however, I haven’t been able to improve much at all. Is there a pre-programmed limit to how strong I can get, and could I reach it so easily? (If it matters I’m a thin man in my 30’s)

the key is variation, if you do one exercise, your muscles will become accustomed to it, and you will not make significant ains in strength.
Strength - Low repetitions of a lot of weight
Toning - High repetitions of a lower weight

There is a lot written about the state you’re in right now in body building books. They seem to recommend anything from shocking the body into continuing to grow by over working yourself, to a week or two of rest.
I’m not a physical trainer, though, so go to your local book store and pick up a few books on physical training. I know with my running some of the guides have helped me significantly and are well worth the price.

At your point, if you have been eating just enough to maintain your bodyweight and training hard with enough rest, you might have reached your potential for a given exercise, given your current physical status. Now, all you can do adjust intensity, duration, and interval of training. This may bring on new strength, and certainly will bring on new size.

Of course, the easiest way to break a plateau is to eat more. I will go so far as to say that, as long as you have everything else in check, you will actually have a tough time plateau’ing out if you are in a significant calorie surplus with lots of protein and carbs. Eating will do wonders to your muscle size and strength, but it will also do wonders to the scale as well, so it’s up to you to set your personal goals and eat accordingly.