I have a lab that was just rescued not too long ago. She is a sweet thing, but after 10-25 mins of chasing the tennis ball or soccer ball, she is unusually tired, so much so that on hot days, she almost collapses. Yesterday, we played with the soccer ball and after 10 mins, she would only lay down. On the walk back home, she was staggering and only wanted to lay. any thoughts?

Have you had a full check up done on her? If not, I'd do that ASAP. Please let us know.

I agree with Korig. Also, what kind of shape does she seem to be in, at the shelter she probably didn't get too much activity, so she maybe out of shape and you'll have to work slowly. Also, it might just be too hot, and 10 min at a time is enough. My Moose (2 years 5 months) is very active, even with his HD...but we usually only do 10 min then rest and then start again, I always make sure he has plenty of water and when its near and/or over 100 degrees out we don't play, unless its water fetch as I'm afraid he'll over heat. Maybe just slow down a little bit and ease her into more activity, but I'd talk to the vet first.

There are some genetic disease in labradors that may be the culprit mention these to your vet, blood work may have to be sent out. But one is excersise induced collapse and the other is degenerative myopathy. EIC is just like what you describe Usually they reccomend no vigouros excersise as the dog can actually die. The dog May just be out of shape and you would want to start slow with just walking. Please let us know what you find out.