too old??

[Angstmufin@aol.com]

Up until now, i've only ridden my Welsh pony in light rides and pleasure rides
besides showing.  He's 17 and in great health, but out of shape.  Is he too
old to condition for limited distance rides?  (20-25 miles)  the farthest he's
gone so far is 10 miles walk/trot.