The Human Machine is not the same for everyone. E.g, I weighed 175 at 5'5" at 12% at 17. I weighed 228 at 28 at 5'5" at 12%. It wasn't because of a miracle potion, etc. It is what my body is. I look at weights. I eat food. I get big. Contrary to what some skinny hater might say, it's actually easy for me. I've been studied over it. Michael Phelps has a disease which allows him to swim better (I forget the name, but, he has it, and it makes your arms and legs longer.) It's easy for Phelps, too. You make lemonade from lemons. You make apple pie from apples, and so on. Logan / flex89 lives with me. He was 135 and having seizures before he came to me. Now, he's a happy, vibrant, 220 pound 20 year old, that took bodybuilding (perfect for a diabetic) and leverage his disease to his advantage. You make lemonade. Logan's HBA1C is now a 6.5, which is OUTSTANDING with an insulin sensitivity of .75. That's the power of exercise and diet.
I'm just entering my 35'th YEAR of weight lifting. I can do 20 sets of legs, after having done HIIT on the stairs in the morning, and go do it again the next day. My recovery is exemplary. Likely, yours isn't the same. I can hold my heart rate at 160 for 20 minutes, any day of the week, at 48 years old. My cholesterol is 130. I engage in disease prevention, rather than disease treatment.
We all have to learn our abilities, strengths, weaknesses, and what we enjoy; what makes us feel good. For me....I'll never be a NBA player. I work with what I have. I excel with what I have.
Your journey comes from within.
Let your body and mind guide you.
Let science and your own body guide you.