How to neutralise the behaviour of gym rats in the gym?
"neutralize" and "gym rats" are definitely not nice words. If you use such words with the people at the gym, it is strange that they still accept you there.
Even if you do not use these kinds of words, you have this kind of attitude, and it is very possible that you express it somehow non-verbally.
It is similar with smiling when talking on the phone. The person at the other end will know that you smile, even though they do not see you.
I have to confront those people every day
Maybe I am wrong, but a pattern seems to emerge. Actually, you do NOT have to confront. Not every day, not even once. You just need to be mind your own business, provide help when requested, ask for help when needed.
they never try to initiate a simple conversations about the workout we are about to do, as they always talk about with other people, and after the workout ends, they just leave the room without a single word
If I understand correctly, they actually work with you, but they do not care to include you in the chat. They do not even have to.
My understanding is that the socializing part is actually a kind of a bonus at a gym. The workout is the main stuff.
(According to "internet wisdom", there are people who go to the gym only / mostly for the socializing and for the selfies. It seems you do not go to that kind of gym with that kind of people.)
I need to know the capacity of my partneres, how much they can lift, how fast they can run, ...
If they do not really require / request your help, you might not need to know. Just guessing. If the workout happens, the knowledge transfer is secondary.
If I know the partner better, then I will push them when they need to be pushed
You assume again, that they consider you as one of them, and that they need your support the way you are ready to provide. Maybe they just do not want to be pushed by you.
I don't know if I need to confront them in person
Again, confrontation. NO, you do NOT need to confront. Whether "positive" or "negative", confrontation is not building good relationships. It destroys them, most likely.
And the bottom line, which is the information you started with:
I'm new there (about three month) however all other people have been a member since a year ago, I can tell there is a special bond between the people.
They are already a "family". They have special ties, special stories, they can do things without sharing information.
They already support you, so you can get to their level. If you want them to trust you, then it should be you who should learn to trust them in the first place.
Imagine this: a stranger appears and sits at your family's Sunday lunch. Or Thanksgiving dinner. Or whatever. Maybe you will accept them there out of mercy, or other reason. Will you be able to involve them in the chats as if he is family? As if he knows everybody? As if he know all stories and histories? Will you answer his questions about your families strengths ans weaknesses? I mean, just because he wants to help pushing and supporting?
What to do: read the answer from @s1lv3r. It makes perfect sense.
Now let's analyze some comment(s):
I was talking about the team work all the time
Yes, you did. But it made perfect sense that you considered to be a team with them, without them having a need to consider themselves being a team with you.
I didn't mentioned the national tournament because I thought it's unnecessary.
That tells a lot about your (missing) communication skills, and your (missing) socializing skills. A national tournament is a thing which changes TOTALLY all social dynamics. Personal preferences MUST (usually) be forgotten, for the sake of winning.
So it's a game day, and I'm still clueless about my roll, because I never confront my teammates.
"I'm still clueless" - it is normally a weak point of the team leader (formal or informal, official or unofficial). The team lead should have made the objectives and strategy clear from the beginning. But the biggest problem is that you did not report to the team lead that you don't know how to integrate into the team.
"I never confront my teammates" - you have one very clear idea, the one confrontation. It is actually very good that you do not confront anybody. Talk and discussions are NOT confrontation. Usually confrontation means conflict - and conflict is something you want to avoid.
All I have written might sound discouraging. However, I think it should be seen only as an eyes opener - that you need to take into considerations things you did not think about in the past.
Unfortunately, I have no idea (my bad) on how you can improve short-term. Long term, the "cheap and easy" way is to read books about:
- communication skills;
- conflict avoidance and management;
Of course, it might prove better if you could attend some trainings, or have some sessions with some specialists on the same topics.
Additionally, you might want to think also to use the services off a specialist / coach / psychologist to help you solve the (generic) anger which you store - the one that I sense from your entire communication.
To get better advice, you should ask another question about how to improve in the few areas I mentioned above. You should also make a reference to this question, so people can adjust their answers to your needs.