Type V Glycogen Storage Disorder (T5GSD) is one of the trickiest ones because it has very little confirmed treatments, especially nutritionally.

Following a strict dietary regiment may reduce liver size and prevent hypoglycemia - this means eating more often throughout the day (in the form of small frequent meals) and eating similar amounts at the same time everyday. Because exercising can prove to be rather difficult in people suffering from this condition, ingesting sucrose immediately before exercise may allow the body enough to work out with. Your physician may be able to give you glucose tabs for diabetics (3 are one dose) - these are good to prevent hypoglycemic moments but would help in your case BEFORE a workout to prevent that. Basically, when you work out you exert ATP (which is energy) - when ATP runs low, it will pull from glycogen (stored sugar) to replenish - because people with T5GSD cant produce the glycogen, going into a small state of hyperglycemia may be a way to allow for there to be plenty of ATP during exercise.

As for fruits and vegetables, the question here is really sugar. Slow releasing sugar is most likely the best, so starchy sugary vegetables (sweet potatoes, carrots, corn, peas) may be beneficial over, say, celery and leafy greens. Uncooked cornstarch not paired with citrus is also seen to help and put someone in a good place glucose-wise for 3-6 hours with only 1-2g (about a tablespoon). The downside is not getting enough essential micronutrients from those foods, so multivitamin supplementation would have to assist in that department. As for fruit, because the general rule of thumb is, the harder it is to digest, the better… this deletes citrus fruits because they are juicy and that is where the sugar is - as for other fruits, most are easily digestible and put glucose in the body right away. I would consult with a physician or in-patient dietician who can see your personal chart to get a good idea of the glucose load you need.