It is generally accepted that the optimal rep range for muscular hypertrophy is around 6-10 reps. And it is also generally accepted that after 3 minutes of rest muscles will recuperate all the energy they can possibly get. (Schwarzenegger, Weider)

Do muscles still achieve optimal hypertrophy when they're tired and they hit that range? Let me give an example. I do 8 reps of 135 lb to failure on the bench press. I take a brief rest, about 30 seconds. To accomodate my current energy level, I must lower the weight to 95 lb to reach failure at 8 reps. Is this second set still achieving maximum hypertrophy? Or must I rest long enough to use 135 lb x 8 reps again?

It is generally accepted that the optimal rep range for muscular hypertrophy is around 6-10 reps. And it is also generally accepted that after 3 minutes of rest muscles will recuperate all the energy they can possibly get. (Arnold Schwarzenegger, Joe Weider)

Do muscles still achieve optimal hypertrophy when they're tired and they hit that range? Let me give an example. I do 8 reps of 135 lb to failure on the bench press. I take a brief rest, about 30 seconds. To accomodate my current energy level, I must lower the weight to 95 lb to reach failure at 8 reps. Is this second set still achieving maximum hypertrophy? Or must I rest long enough to use 135 lb x 8 reps again?

Schwarzenegger, in his Encyclopedia of Modern Bodybuilding, has instructed never to rest long enough to completely recuperate. His reason was to not let the muscle get cold and to feel a better "pump". However, Weider refutes Schwarzenegger's advocacy of the "pump". In one of Weider's videos (4:29), Ms. Olympia 1982 Rachel McLish says:

You can go for the burn all you want and you will not get results.

So Weider suggests longer rest periods for more mass. Who is right?