Not to old providing they are healthy with no degenerative joint problems
i think any dog can be trained, its definatly worth a try, try them both, you may be suprised, the laziest looking dog joined our club last week, but he was very very nervous, with a little encouragment and some cheese ;P he conquored his fears and went through the tunnel and over the dog walk, i would recommend agility to anyone, crufts champions have been 9 years old
its such good fun, good luck with it
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