I just started a modified GVT program and was wondering if I should force myself to increase the weight I lift every week? I was on a 5x5 previously where every week I "HAD" to increase the weights of the lifts.....
It depends how you modified it.
I would do it as is (or not call it GVT) in which case you don't up the weight until you complete all 100 reps for a given exercise with the correct technique, rest period and tempo.
I hope this helps.
If you read the article in full it should cover these questions for you.
It is described as a 'patient lifters method' of overload, you do not increase the weight in subsequent sessions unless you complete all 100 reps.
10, 10, 10, 10, 9, 9, 8, 7, 7, 6. Same weight next session.
10, 10, 10, 10, 10, 10, 10, 10, 10, 10. Move the weight up.
If you are looking for strength increases GVT is not the programme for you. It is aimed exclusively at size. Some gain strength on it, others feel they temporarily lose it. It will increase work capacity but not maximal strength.
Increase the weight by 2.5%. Don't try and jump 25lbs in one workout.