It possible to switch from being "shower" into "grower"?

I suppose you meant the other way around : most men want to be showers.

• Growers : men whose penis is compact at rest, but stretch to a normal-sized erection when aroused, thus displaying a huge increase in size between rest and arousal. (~2:1 ratio, quite often)
• Showers : men whose penis is already long at rest, and raise to a normal-sized erection when aroused, thus displaying a slight increase in size between rest and arousal. (~1:1 ratio) 

The variance in men’s penis size in the flaccid state is extremely wide, but this variance lessens markedly when comparing men in the erect state. Generally speaking, men who have a relatively small penis in the resting state will note a marked lengthening of their shaft when erect, while men with long dangling penis will find that their erect penis is just a little bit longer. Unfortunately, of course, small penises don’t always turn out to be growers. As for long growers, they usually don’t complain : they’re the one who become porn stars, usually !

This being said, you cannot really switch from grower to shower. That’s how you were build. Inside the grower’s penis, there are a lot of collagen bridges inside each pockets that add up to form the corpus cavernosum. These collagen bridges acts like elastics or springs that collapse these individual pockets when they are not engorged. Resulting, of course, in a marked reduction in length in the resting state. This ensures that the penis won’t get in the way when running or sitting, for instance, so while growers won’t enjoy big bulges in their pants, they won’t be annoyed by their cock’s resting position in their day-to-day activities…

While it has been shown that very little can be done to increase the erect penis length, it is possible to modify in part the penis’ resting length. How ? “Simply” by breaking or at least stretching some of the collagen bridges. This will result in corpus cavernosum pockets that are not as collapsed as before in the resting state, hence a longer resting penis. Some exercises, like jelqing, will help achieving this. Pumps will also help. In both cases, however, you should not go over board : if you damage the corpus cavernosum, scar-like tissue will form, causing a decrease in the erect length, something you don’t really want, I’m sure !

(1) The collagen’s quality also drops over time (explaining wrinkles, amongst other things) : this is why men often have longer penis at rest in their forties compared to what they had when they were 20… This is true, of course, provided they are not hypogonadic (provided they don’t have a low testosterone level), and in good shape, generally speaking.

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