If I may, just because you are not as "fit" ( in terms of muscle mass/body mass) doesn't necessarily make you "unattractive". Some people might well like a person with a big personality. Some or maybe most (which I disagree with) won't, that is also fine as it is a very subjective.
I think that to treat and value a person's sexual prowess and or attractiveness by size, weight and or muscle mass is very demeaning. I can easily see this "hotness" or "league table" mentality can lead to the creation of an inferiority complex within many LGBT people (I am not as "hot" therefore I am worth less and thus deserve less).
For a community where a large percentage - somewhere between 50% and 80% of members suffers or have suffered from bullying, abuse and or some form of mental illness. (Stonewall) The induction of "superior/inferior" thinking and derived action based on "hotness" (attractiveness itself is conditioned by media and influence by many variables. The prevalence of "white/real men no blacks no Asian" etc. "peacock"s, could very well be due to that most gay tolerant countries are mostly populated with Caucasians) could very well promote a even more unspoken mainstream "caste" social structure. A very backward development to a community striving for social equality.
If a LGBT person who has already been made to feel humiliated by homophobes, he or she could easily feel even more degraded when he or she realises that her appearance (assuming cannot be changed in the short term) is regarded to be inferior.
To conclude and to answer your question. Please don't perpetuate this idea that:
"I have more muscle therefore I am better than you, therefore I am going to treat those who have less muscle less well because I perceive them to be worth less."
It really harms people's confidence and perception about themselves. To extrapolate even more, it could harm the reputation and perception of the LGBT community.
If you are "chub" and it is endless fulfilment of lust that you want, you know what to do.
Otherwise just keep looking and be yourself.