The foundation of 5x5 is pretty simple 5 reps x 5 sets of each exercise. The 5x5 system is one of the oldest muscle building programs and has been around since the 70’s. Some say the 5x5 is good and on the other hand some say the 5x5 is bad; I guess it all boils down to what type of results you are looking for. There are a few ways I have seen the 5x5 muscle building system implemented.
The first way that people use the 5x5 system to build muscle is that they warm up to a weight and then stick with that weight for 5 sets of 5 reps. You would need to pick a weight that you can handle for 5 sets. Set number 5 will be the only set that is difficult and or where you may reach failure. This is a ok method to build muscle but largely a waste of time for anyone but a beginner. This type of 5x5 routine most of the training volume is at an intensity that is far too low to build muscle effectively. Personally, I think the 5x5 system is only viable for beginners and early intermediates. I don’t know if five sets are really necessary though; 3x5 is probably better in most cases. In my experience 2 to 3 sets per exercise is all that is needed to build muscle effectively.
Another way people utilize the 5x5 system is by starting with a heavy weight on the first set that they pretty much can only get 5 reps and then lower the weight with each following set. In my opinion this is a bit much. The only set that was worth doing was the first and maybe the second. This is not the optimal way to build muscle but the best way to build strength. The lower on the rep range you go the less muscle you build but the more strength you build. A perfect example of this is to take a look at power lifters and bodybuilders. Bodybuilders have more muscle but less strength compared to power lifters.
The third way I have seen 5x5 system used to build muscle is to work your way up to 5x5 with a heavy weight that you can barely get 5 reps with the first and second sets. Progression is made each week by trying to reach 5 reps on the third, fourth and fifth sets. Of all the 5x5 variations this is the best to build muscle but again 2-3 sets per exercise is all that is needed and the reps are a bit low for building muscle efficiently.
The last way I have seen the 5x5 system used to build muscle is by doing five increasingly heavier sets. The last set is the only tough one. In essence the first four sets are just warm ups to the last set which is a 5 rep max. It’s really 1x5 and not 5x5. If I had to pick any of the versions mentioned to build muscle I would not choose either of them. 5x5 system reps are too low on the rep range to build a lot of muscle but instead it should be used if you are looking to build strength. As mentioned earlier if you are trying to build strength and not muscle 5 reps and below are best, if you are looking to build muscle and strength aim for 6-10 reps. Of course you can build muscle using the 5x5 system but it will not be as much muscle if you had used a higher rep range. I suppose if you are taking an active break from the gym then some of the variations of the 5x5 system mentioned above could be of some use.