Errr....well... gosh darn.... "depends". (again! :dogohmy
Some days the dogs are great, having fun, doing well, and the training session can easily go an hour. But it isn't a full hour of training because I pause for play. So you could say I train for 10 or 15 minutes at a stretch.
Then there are those days when absolutely nothing is working, the dogs have forgotten their names, or think catching grasshoppers is much more interesting (Bonnie), or have decided to dig for mice (Joey), and can't settle down and focus. In that case, I forget all about training and just throw a ball around and play a bit to exercise them and blow off some of that teenager energy.
Or you could say that we're almost constantly in training, except that it's the dogs trying to train me! They're pretty good at it, too.