Evolution: Yes, there is a way to change genetics.
Evolution! And it happens much quicker than you think. It has been shown to happen generation to generation, and I believe much quicker (no proof yet), and I actually believe much much quicker in times of Serious distress.
It has been shown that crash diets and famine like diets (why I don't really recommend keto for under high bf%s) and of course, actual famine, drastically increase the propensity for overweight children. This is done by turning on a certain switch in your body that otherwise would not be turned on.
Hormones: hormones are another way to screw up your lean gains. Hormone problems can come from things as obvious as genetics, to things as abstract as those hard plastic water bottles that you drink out of. Hormones are a major determinant of lean mass gains.
The First Ten: I like to call this "The First Ten," but what I am actually referring to is the first 10-18 years of your life, depending on how fast you matured. your nutrition during these crucial years are, IMO, what determines what you will look like the rest of your life. If you are fed really healthy foods and your body adjusts to regular protein intake along with healthy carbohydrates and fats, then you will have a much greater chance of achieving things others wouldn't. However, if you eat sweets all the time, your body adjusts to the use of fast carbohydrates for energy; and the way your body adjusts to these changes is in your genetics. For example, If you eat sweets very frequently during your puberty years (me

), then you will have a high insulin spike quite often. Because insulin and other hormones react together, example growth hormone, you might cause problems such as stunting your growth.
Steroids: ahh yes, the artificial way of evolution. This is a fantastic way to change our genetics and achieve feats not normally possible. This is like flooding an economy with resources it was never capable of retrieving before, of course there will be fast growth!
No fat gain, but also not much muscle gain either. Pros and cons to everything my friend.
I am on trt, but other than that, no cycle. I have cycled, but long before trt so all gains were lost within months. Actually probably hindered my gains for the future.

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