When I mentioned bladder muscle exercises in an e-mail exchange with a teenager a few years ago, he responded:
"A couple of months ago the doctor gave me some instructions on exercises to help strengthen some muscles, and I think it helped some. I used to wet every night, now I only wet 3 or 4 times a week (well most of the time anyway.) Sometime I wake up while it is happening."
There are two bladder muscle exercises I am most familiar with. Any person who has experienced reflux or kidney/bladder dysfunction other than sleepwetting or small bladder capacity should probably seek an evaluation and advice from a urologist or continence care clinic before trying either exercise.
Exercise One -- Stop and Go
(This is called squeezies by some kids.)
On every trip to the toilet, try to stop urinating completely and then start again five times before getting empty. [Boys may do better at this sitting so they don't have to aim at the same time.] Then make sure the bladder is completely empty [very important!] and then do the same squeeze and relax pattern at least five more times. Also, at times when there is no need to urinate, practice relaxing and tightening those Stop and Go muscles five to ten times. The purpose of this exercise is to get a better sense of where the bladder sphincter muscles are and how to make them do what their owner wants them to.
But don't let stopping while urinating become a habit that extends beyond the training period. That can turn into a pattern of incomplete voiding that may lead to reduced capacity, infections, and other problems sometimes years later. Combining different bladder exercises may make a person better able to sense the beginning of urination while in light sleep periods and also better able to stop wetting sooner while waking up.
So what about waking up while wetting? It may seem like a real downer when it happens, but it isn't. When sleepwetting control has been delayed, it is likely to develop in stages, not all at once. Waking up while wetting is an improvement over waking up anytime afterwards. Smaller wet spots are a sign of progress. Getting to the bathroom with only damp training pants beats going there to remove soaked ones. Waking up in the morning wet but with a full bladder is better than waking up even wetter and empty.
You can develop your own program combining bladder exercises and imaging with a wetness alarm. Each teaches a different skill. What a wetness alarm does by itself, mostly, is teach a person how to wake up sooner and sooner while wetting. The muscle exercises strengthen the ability to sleep longer before wetting and to stop wetting sooner when the alarm (or the bladder/brain connection) goes off. Visualization exercises or imaging can connect these elements into a program of more lasting value.
I am NOT a medical professional and do not offer advice that should be taken as medical or therapeutic in intent. Always consult a doctor for medical diagnoses and treatments. I have researched the area of teaching bladder control and managing bladder disabilities as part of volunteer work with incontinence support organizations and families of children with disabilities. I am a writer, actor, storyteller, children's bookseller, and parent of two young adults. I serve as list owner of the e-mail lists EnuresisKids [moderated] and EnuresisParents.