ExRx.net

Okay so from what ive been reading it says to just keep using the same reps and keep adding weight as needed and change the exersizes every few months, however what i do is keep most of the same exersizes and every 8 weeks i go from low rep high weight to high rep low weight so 3 sets of 6 reps to 2 sets of 20 reps, now is that good? or should i always be doing 8-12 reps and a couple sets?

You right about switching rep ranges periodically. This concept is called periodization: http://www.exrx.net/WeightTraining/Periodization.html

A change in range can be good. More then 12 and you get into the endurance range though. More then 15 and you're wasting your time. Unless you are doing warm ups or rest/pause of course.
You can also just do more sets when you go lighter.

yeah my trainer got me into the 2 sets of 20 thing and it does feel good to do and does increase my endurence and did increase my muscle size, ill have to look into the not going past 15 thing, but if i only do 15 then its not a huge difference rep wise 18 to 30 this way theres a big difference from 18 to 40 thats my thinking on it anyways...

I dont quite understand what you mean by 18-30 rep wise and 18-40 being more of a difference?

what i mean is you need to change the reps up to avoid adaptation right so going from 2 sets of 20 reps to 3 sets of 6 is a much bigger difference in reps then from 2 sets of 15 to 3 sets of 6

Oh i see, you are talking about total reps in the workout.

Well, yes going from 2 sets of 20 to 3 sets of 6 is a big change but so is 2x15 to 3x6

Going from 2x10 to 3x6 would be a big change in my opinion.

A classical example of periodizing for gains by reducing volume is going from a 5x5 routine for 3-6 weeks to a 3x3 routine for a few weeks.

personally, I have found making small rep changes and exercise changes simultaneously to be the most beneficial to me.

so its worth while changing from 3 sets of 6 reps to 2 sets of 20 every 8 weeks or so? i figure i wouldnt loose too much endurence while doing the low rep phase and i could build muscle as well as increase endurence

heavy weight and reps that are low. That is the way this fat man grows.

Heres the problem. While doing the 2 sets of 20 for EIGHT weeks you will most likely lose most of the strength gains you achieved in the 3 sets of 6 phase! That is way too long to be going that light. If this is what your trainer is advising, well, id advise getting a new trainer! Sets of 20 or more will give you a pump, but if you want muscle that will last i wouldnt go over 15 reps. Unless you were training for a bench rep competition (like 225 for reps or something) i dont see any point in training over 15. This trainer probably wants you to have the pump during the workout so you'll feel like's hes doing a good job...

okay i had a talk with my trainer and read some more and he only did the 2x20 thing with me because i JUST started lifting with him 8 weeks ago and now he suggests from 6x3 to something like 10-12x3 sets which i agree with, he said i should just keep doing the same thing until i plateu and then change to the other

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