I’ll give you my take on this topic as someone who has dieted down and bulked up ~8 times now, and being involved in the drug free bodybuilding community.
“It must have taken you so long to build that physique.”
There’s some truth to that statement, but fulfilling your natural genetic potential does not take as long as most people think.
And I feel like the bodybuilding community is really disingenuous on this topic, claiming to be making progress every year as they repeatedly bulk up and cut down, when they actually do not look all that different.
Hypothetical scenario (assuming OPTIMAL nutrition and training, preferably under the guidance of a competent coach):
Novice trainee with no experience in nutrition or training. Set up a MAINTENANCE diet with at least 1 g of protein per pound of lean body mass. Develop skill in resistance training. Do this for about 3 months. Trainee can gain muscle and lose fat during this honeymoon period.
After the honeymoon period, if body fat is too high, spend 4-6 months leaning out; create a clean slate to bulk from. If body fat is reasonable, proceed to ~2 years mostly focused on gaining muscle. Push the envelope a bit with the body fat.
Diet down to very low body fat in 4-6 months.
At this point, you are now in the ballpark of your genetic ceiling.
Bulk up 25-30 lbs over the course of 6-8 months.
Diet down to very low body fat in about 4 months again. You should look better than the first time you dieted down.
Bulk up 25-30 lbs over the course of 6-8 months.
Diet down to very low body fat in about 4 months. You’ll probably look slightly better than the second time you’ve dieted down. At this point, you’ve mostly hit your natural genetic potential.
The idea here is the first time you diet down, it can be such a shock to the body that you will tend to lose a significant amount of muscle. Then your body acclimates on subsequent fat loss phases—it becomes easier for your body to hold onto muscle as you diet down.
This tends to bear out with athletes—they almost always look better after their second prep (compared to the first), less so on the third, and then progress really tapers off.
The only time I really see people make noticeable improvements in their physique from for instance—the fourth to fifth prep—is if they were doing something really subpar with their nutrition (e.g. no refeeds) or training (e.g. backing off training intensity too much, rep range too low, subpar exercise selection, subpar exercise technique).
Recommended rate of weight gain for bulking when trying to gain muscle: 1 lb per week
Recommended rate of weight loss when trying to lose body fat (starting from reasonable body fat levels): 1-2 lbs week. When very lean, .5-1 lbs per week.
In total, around ~5 years to hit natural genetic potential. Again, this is under ideal circumstances with optimal nutrition and training guidance from the get-go.