miltary question

Hello everyone,
My wife and i are hoping to move to Switzerland next year. my main concern is that i may have to do military service once i arrive(i am a dual citizen). I'm 25 now but will be 26 by the time we arrive. So my question is if there is an age when the military will not accept people to begin service, i know most kids start at 18-19. or is there an alternative?

thanks,
Alex