irregularity in arpeggios

[mirtilla]

Hi everyone, I'm not english. Excuse me if I write some mistakes in my posts 
I've studied piano since I was 9 (I'm 23  ), at he beginning giving exams at school but now I play just for my pleasure.
Here is the problem: playing simply 1-2-3-4-5-4-3-2-1 (each second and faster) I'm not regular, it's difficult to separate 4 from 5...
I'm relaxed with my arm (I think so  ), don't feel pain and not rigid.
I know it's quite simple and one of the first things that are teached but I cannot solve this! Could you help me?
Thanks

[kard]

The Goldberg Variation no. 1 kept annoying me specifically because of those arpeggios  One important trick is to have your basic keystroke solidly under your control- the downstroke, hold, and release (which I'm assuming you do). The second is using parallel sets as described below.
https://members.aol.com/chang8828/contents.htm   
And for those wondering, Yes. That book is my music degree. I will keep flaunting it until something better comes along.
You will probably get more immediate tips and tricks from the other members

[mirtilla]

Thank you for answering and posting that interesting link