Tiffany bag pot

English equestrian wear - can men wear those tight pants? - equestrian men jockstrap

I am working on writing a story, and I need some information to bear on riding - I do not know much.

1) The tight pants, take the women - are just some of the men wear pants like that, or those that are wider above the knee?
2) Is "saddle bags" the actual name of the latter, even if they are larger than the knee?
3) For the driving style is "English" as "Doma", or is this subset of the above?
4) What is wear a shirt for a man with these pants, as part of the official jacket?