Is changing your workout routine weekly essential for bodybuilding?

In short NO. You can actually keep the same workout for your whole life if you know how to avoid overtraining.

But can I recommend doing A high intensity resistance program.

I started Mike Mentzers Heavy Duty and I am seeing gains after every workout. I really didnt think it was possible but it is.

But no dont worry about changing every week, make sure you target the muscles you want and just do what works for you.

1

The idea is to change the parts of muscles being exercised, so more likely to build more of each muscle.

How often seems up for debate. First I have heard of weekly.

Yes, you need to work on all of your muscles, not just the same ones over and over again. Changing your routine with different exercises works different muscles.

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