LOL............ If a dog doesn't posses stamina, just like speed, no amount of work will improve it that much. Yes, hard work will get a dog to its running weight, fitness levels but hopefully everyone who runs a dog has their dog to this level before the season starts....
Heard it all now.You cant improve a dogs stamina with hard work.
of course you can you improve its fitness levels to increase its stamina you cant tell me 2 identical cross dogs say one has done nothing for 3 months and the other has had regular work and exercise the one thats had regular exercise and work is g