People say that certain types of exercise is not good for growing puppies, such as ball throwing because it involves sudden jerks, turns and twists I think? I tend to agree, but then I thought: if so, could puppies playing with each other also be not good for them? Due to the amount of jerks, turns, twists, jumps and some unnamed but truly breathtaking acrobatic manoeuvres that they perform during the play continuously.

The problem with ball play is twofold.  One; it does indeed involve these sharp, sudden movements but also very high impact events - when the dog gets to the ball there's often a sharp stop as they pick it up, when the feet plant into the ground and you can see the judder through the whole body.  That is massive impact on all the joints, very bad news for a growing skeleton.  Two; repetition.  These events are happening over and over, putting excess wear on those joints.

In puppy pla, not only is it often more gentle than the immense forces involved above (and I am making a mental note here to see if I can find any quantitative information on those for future use), but it's much more varied and not the same movement repeated again and again.  Many more muscles are involved, so they're getting toned up nicely, and it improves coordination and balance.  They can also stop if they are uncomfortable but ball chasing tends to bring in an element of obsession for most dogs, and they will keep running long past injury or discomfort.  I've seen that happen many times, including with my own Phoebe in her last home - she had a soft tissue injury after she ran shoulder-first into an iron bench (chasing a ball, of course) and she continued to chase one despite being in obvious pain and with a bad limp (and despite me telling the owners to stop throwing it because she'd never heal otherwise and that leg can still be a problem today).

That obsession can lead to other problems too but that's behavioural rather than physical.

Thanks Nikita that makes sense, except this part worries me a bit:

> They can also stop if they are uncomfortable

I guess it might be breed dependant, our terrier puppies are somewhat non-stop. An activity of playing with another dog is highly exciting (though to be honest any activity is exciting for them), and it seems to me that their minds want going long after their bodies tell them to stop.

I was thinking about this in a different context also, the recommended level of exercise for the puppy, where the usual advice is 5min per month of age enforced exercise (e.g. walking), and free play as much as the puppy want because when it is free the puppy will stop when necessary. But what if the puppy won't stop? How much would it be advisable to restrict free playing activity?

My 7 month old plays with other pups and older gentle dogs until he lays down (usually about 10 mins) and then I put him back on his lead for a rest. If they are still about he gets another play. We do no ball throwing but I will do fetch a few times with a rope as it gets rid of ‘the crazy’

I figure if he didn’t run or do a 40 min lead walk (usually takes over an hour due to all the sniffing of literally everything) he’d only be tearing about the garden or house anyway and those are much smaller tighter places to be running about in.

We also do training to try tire him out mentally but he’s a 7 month old boxer so focus is about half a second at present....

Fair points!  What I should have said then is that it is easier for the pup to stop if they are uncomfortable because the obsessive element in puppy play is not on the same level as it can be with ball chasing.  But yes, that could still be an issue.

It's hard to say how much we should step in - common sense has to play a role, although as we all know it isn't that common!  What I tell puppy owners is that if the pup is starting to get a bit manic in their play, or extra chompy to people, then they are getting overtired and need to be made to rest (crate, pen etc) as they are struggling to stop themselves.

Sometimes puppies are like young children - don't know when they've had enough.  I would say a lot depends on the breed and whether the two puppies are roughly the same size or not.  Not having had terrier puppies specifically I really don't know but with our Bassets, I always found when one had enough, the playing stopped and they simply went to sleep.   I never had to call a halt.   If you feel your puppies are overdoing, then step in.   Otherwise surely puppy play can only be good, physically and mentally?