for each coach, your player gets 1 traiings point more. for instance: if you have all coaches at 1 (like you do) then you get 1 point more every trainingsupdate. if they are at 20, you get 20 points extra.

And no, you should not get any kind of coaches at this point. you have to invest in your stadium first. then you can make the big bucs
and then you're ready to get some coaches

thanks for the feed back everyone keeps saying "coaches" if you have one fitness coach with a rating of 20 is there a need for another fitness coach?

If you mean, once you buy a 20 Fitness Coach, then you want to buy a 20 Defensive Coach, but keep the Fitness Coach, then you have to buy the Fitness Coach again at the same time you buy the Defensive Coach. I try to look at it more this way: I'm buying a coach with a specific set of skills, rather than a Fitness Coach or a Defensive Coach. The first coach I bought had skills of 1-1-1-1-20. Then say I wanted to hire a more defensively minded coach, I'd want to find a coach of 1-20-1-1-20.

almost right.
you don't just maintain your 20 fitness coaches, but you also have to buy them again ( pay the sign on bonus for them again). that's why it's wise that, if you can afford it, save a lot of money, and then get all coaches at 20 at once, so that you only pay the sign on bonus once.