I just finished reading an interesting paper on how often you should train. I mean I literally just finished it, so I may have some other thoughts later.
This study was just published a little over a month ago, and it has lit up a lot of the discussion boards I'm on. I believe it is an important study in that it is the first real look at how often you should train your dog for the optimum acquisition of a behavior, but the biggest flaw - which was discussed at length on one of the boards - is that the dogs used were laboratory animals used for drug testing that did not have the same stimulus as a household pet, for example.
That being said, to put my interpretation to the findings, it shows that it is just as important for the dogs to have time to process the information they have learned as the training session themselves. What the study found was that one session, one time a week showed the best acquisition of the behavior. The worst were the dogs who were trained in three back to back sessions every day.
My initial thoughts are pretty much the same as before I read the study, although I may have other ideas as I think over what I've read. Particularly when you first start training your dog, keep the sessions short. I recommend in my puppy classes that you start with about five minute training sessions once a day. Always keep an eye on your dogs stress and frustration level and if they are getting too stressed, frustrated, or distracted, stop. Once the dog starts getting used to the training you can extend the time, although I usually don't recommend going over 15 minutes. Also, once they start to figure out the training process, you may be able to train two or three times a day.
Unfortunately, we can't draw any definite conclusions until more research is done, but this is a start. For the time being, keep your training sessions short, fun, and be aware of the state of your dog. If he's not having fun, stop and come back to it later.
Demant, H., et al., The effect of frequency and duration of training sessions on acquisition and long-term memory in dogs. Appl. Anim. Behav. Sci. (2011), doi:10.1016/j.applanim.2011.05.010
