You'll often hear a rule of thumb, that puppies should only have 5 minutes of exercise per month of age... so an 8 week old puppy can have 10 minutes, a 12 week old can have 15 minutes and so on.
Sometimes this advice will be supplied with an xray image of a very young puppy whose bones are not fully hardened yet, and so it looks like none of the joints are actually connected - they are, but the growth plates are not closed and the bone density is not high enough to register properly on x-ray plates.
Breeders will often send puppies home with dire warnings that they must not do stairs, must not run, play with other dogs, go for walks... ad infinitum really!
But is this necessary, is it practical, is it the full story?
It is true that at 8 weeks your puppies joints, bones and muscles aren't fully developed yet. Depending on breed, they won't be 'done' until somewhere between a year for tinies and even 3 years for giants.
But does that mean 'no exercise', what sort of exercise does this really apply to?
In fact the truth is, some exercise is good, some exercise encourages cartilage to develop its proper thickness, stiffness and density. Some exercise helps build strong bones, strong muscles and a healthy puppy.
And some could be damaging.
The '5 minutes per month of age' rule was never really intended to be for all dog breeds, nor was it intended to cover ALL forms of exercise. Originally, it was a shorthand way of suggesting that on lead exercise where the puppy has no choice but to keep moving, often on hard surfaces, should be limited, and I agree that it should... but not because it's likely to damage joints.
Trying to force a puppy round a long walk on the lead is likely to cause a mentally overtired, overwhelmed puppy. You may see them grinding to a halt and refusing to move, or grabbing the lead, jumping and biting at the owner's legs or hands or other general 'melt down' type behaviours.
That's because puppies, even up to the adolescent teenage phase, will struggle with the things a walk really asks of them - they must experience and cope with all the sounds and sights, all the traffic whizzing by, the weird smells, the sudden noises of back-firing cars, doors slamming, people shouting, cyclists hurtling past. It is tough out there.
Add to that, the puppy is on a lead, they cannot escape, choose their own pace, run away, they are trapped and this may be very stressful.
They are likely also being asked to match pace to the owner, not pull on the lead, pay attention, comply with cues like sit or down - effectively many walks are like you trying to complete a degree level exam whilst abseiling down a cliff face, which is on fire... Very stressful indeed! For this reason, limiting walks to very short trips out, but offering them frequently, is a good idea. But that does not mean you need to strictly limit a puppy's physical exercise to barely anything for possibly the first year or so of life!
Common sense applies!
Avoid sharp twists and turns and highly concussive exercise on hard or rough surfaces.
This means that those ball throwers and chasing balls or toys is probably out for very young puppies and for larger breeds with a lot of growing to do - and any such games should be gentle, on the flat, and practice sending the dog out after the ball has stopped moving rather than whilst the ball is in the air to limit jumping, twisting and sudden stops.
If you've been gently rolling the ball to your small breed puppy on your nice smooth lawn - crack on, that's fine.
If you've been pogging the ball half a mile down a steep hill covered in rough tussocks of grass, or whanging a frisbee up in the air on the tarmac playground so your dog leaps up and crashes back to earth with it - stop right there, that ain't sensible, no matter how old your dog is!
Stairs are often a big stumbling block (ahaha see what I did there)...
Many breeds come with a warning that they should not do stairs, yet the received wisdom is that puppies should sleep with us, and possibly for long periods whilst they grow their confidence, learn where the toilet is and generally how to sleep through the night. Most of us have our bedrooms upstairs so .. do we leave our puppy to cry it out, or spend months sleeping uncomfortably on the sofa as our giant breed puppy must NOT do stairs? Again, common sense applies here. A single trip up the stairs at night and back down in the morning, or even another trip during the night for a toilet break will NOT break your puppy if you walk them up and down slowly, holding the collar or harness so they cannot fall, slip, gallop up and down or leap the full flight! Of course allowing your puppy of any breed or size, to use the stairs as a racetrack, leaping up or down multiple steps, twisting and turning and taking steps three at a time, is risky - but it's not necessary either! Gate off your stairs and supervise your puppy up and down them a few times a day only when necessary. Simples really!
What about jogging or running, or taking up sports?
Most dog sports will have a minimum age they can start to train, and then another to actually compete. That doesn't mean you can't build your dog's fitness, but it should be done the same way you'd get an athlete fit for sport or competition - gradually, with plenty of breaks and rests, in short bursts and keeping an eye on the types of surface your dog is running on.
Keeping your puppy lean and healthy will do more for their joints than locking them up and preventing them running around. Overweight puppies and older dogs WILL cause damage to their joints no matter what exercise they do - make it a habit to assess your dogs physique and condition accurately and truthfully. Remember that on some areas of your dogs body such as across the ribs, fat build up can be quite hard and can feel like bone in some cases!
Don't kid yourself - puppies should NOT be fat, there are NO breeds of dogs that should be fat!
Here's some checks you can do on your dog:
Stand behind your dog and look down at their back - can you see a defined 'waist'? You should be able to, though it will be more clearly defined on smooth coated breeds, so get in there and feel for it too!
Ribs - can you feel them, are they really ribs or is it hard fat over the ribs? You should be able to feel them fairly easily and on smooth coated dogs you should be able to see the last few ribs easily if the dog stretches or turns.
Chest - reach between your dogs front legs and have a scritch here - can you grab a handful of flab, is it soft and doughy? You should not be able to do this on any breed, though some may have some loose skin here. This is a place where the overweight dog will put on loose soft fat and its a good indicator you need to reduce calorie intake and up the exercise.
Pin bones/hips - across the back of your dogs pelvis, you should be able to feel the pin bones at the top of the hip joint on either side of the spine. In some breeds like Salukis and Greyhounds they may be fairly visible, in breeds like Labradors they should not, but the space between them should be flat and smooth.
Spine - some breeds should have fairly prominent spiny bumps in the lower part of the back, some shouldn't but ALL should have well defined 'fillet' muscles that run either side of the spine. If your dog is soft and flabby here they lack muscle tone, if the spine protrudes and there is very little fillet muscle, your dog is too thin, even if it is a skinny sighthound!
Food! It's good practice to feed according to work done - this is common in the horse world and absolutely unheard of pretty much anywhere else. For puppies, most breeds can be given almost as much as they would freely eat in one sitting - there are some exceptions to this rule and if your puppy will eat so much they make themselves sick, obviously don't do that! For adults however, once you've calculated roughly how much the 'average' dog of their breed/type needs (check the backs of some food packets, for raw feeders its around 2-4% of their correct adult weight) have a think about how much work your dog is doing. If it's a hot day and your dog is lazing around on the sofa doing nothing, they may need a little less dinner! If it's been a busy day and your dog has run some agility training, been for a run with you, had a swim, climbed a mountain, then they might need a bigger dinner! If you get into the habit of thinking about how much food your dog needs daily, and don't blindly follow the guideline on the back of the packet (which are overcalculated anyway to ensure no ones dog starves by following the pack guide!) you are far less likely to have an overweight dog who damages his joints.
What about play, what if my puppy is an idiot?
Again, apply common sense - if you can see your puppy is being distracted by play into doing too much, running themselves into exhaustion either by kids or by another puppy or older dog - step in and stop that, insist on breaks and rests!
Some puppies will flop down and rest themselves, and some puppies are absolute mayhem machines and will not!
So can I take my puppy for a nice day out with the kids?
This entirely depends on your puppy, how old they are, how busy that day out will be, where you are going, how hot or cold it is... Generally speaking, yes you can - if you can carry your puppy then you can give them breaks that way. If you cannot carry your puppy, you'll need to factor in frequent breaks for them to rest and chill out. Plan such expeditions to quieter places where it's less likely your puppy will be overwhelmed, and make sure you take into account your puppies need to take things at her own pace, so that if she does grind to a halt and need to sit a while and reassess things, that doesn't cause frustration to the people you are with! Take food and water with you for your puppy and offer drinks regularly - little puppies can get tired very quickly (even if they are large breeds and not physically all that small), they do need to eat three or four times a day when very small. If it's cold out, remember that small puppies, even of long or heavy coated breeds can get cold quickly and can use up a lot of energy trying to stay warm - take a coat or a blanket and don't overdo things!
So to sum up... Good:
Gentle paced walks
Frequent short walks rather than one long one
Consider your puppies nature - manage them if they are silly!
Consider terrain and weather conditions
Prepare for your puppies needs
Bad:
Uncontrolled zooming up and down stairs
Exhaustive play with others
Forced route marches
Overweight puppy/dog
Extreme hot or cold weather
Overwhelming environments or walks too long for puppies attention span
Enjoy your puppies folks - sensibly!