As for race nutrition, consuming 60-90g of carbohydrates per hour is ideal, in whatever form you feel comfortable with. This could be fluid, bars, gels and/or blocks. You should try to mix things up on the bike with ‘real food’. Something like a jam sandwich or rice cake is easily digested and not as sweet as manufactured bars. Just remember that it’s easier to digest bars on the bike, not the run, and to feed at regular intervals. You could set your HRM to remind you to eat/drink every 15mins.