'Specialists' don't recommend throwing with balls and such kind of things to exhaust your dog. It triggers their hunting instinct, adrenaline gets released and *boom* you dog is good to go... on for hours. If you really want to make sure that your dog is 'exhausted'/fulfilled I would recommend doing some 'brain work'. Just let them sniff a lot. Hide things, let them search it. Make them work for their food.
A sniffing mat is an easy example but there are more 'complex' games you can play that aren't physically exhausting but mentally. (If you search on youtube; brain games for dogs. There are many examples)
And of course, bones to chew on. (Antlers par example, -pig- ears, skin,... will keep them busy for a while. A Kong is also an option, the other 'natural' things tend to be kind of... smelly from time to time. But you dog will enjoy them.)
Most dogs can run for hours, sleep for an hour and then continue. It's what they are made for and like this you also built up a lot of condition/stamina. So in the end they will always need more in order to be/feel fulfilled.
I realized it's an 'older' post you replied to. But nipping may also be a sign of being overworked/stressed.(Not saying this is the case) If your dog is too active and doesn't know when to stop (like a lot of border collies do par example) it's also important to 'force' them to take some rest. You might give them something to chew on, put them in their basket/wherever they prefer to rest and make sure that they stay there/don't come to you to play.