Make sure they get enough sodium, potassium, magnesium, and zinc especially. Very important in energy metabolism and thus alertness.
A supplement like Spike would be a good idea; Power Drive or similar blend as well.
Good ideas for physical training, though correcting imbalances about the wrist, shoulders, and neck should be the main focus.
Flexibility, too - easier to sit for a long time if you're not tightening up.
As loathe as I am to suggest it, some longer-duration aerobic work may be in order too, or ultra0high rep work to increase cappilarization and bloodflow capabilities.
Just the ideas OTOH