Hi , regarding food on long runs, check out Tim Noakes MD " Lore of running".
You should , with a varied mixed diet have enough available energy stored in you body to last for runs/races of 90 mins.
I must say that the hype around energy drinks and gels has been a triumph of marketing , there is no need for the amount energy products that cyclist/ runners are consuming.
The problems associated with "been unable to go the distance " more often than not is down to sufficient training and pacing not to lack of nutrition.
I have run and raced for 30 years, training upwards of 110 - 120 miles a week and never once "bonked".
My advise to any athlete would be to get your overall diet right , and train enough for the distance you are cycling/running /racing.
regards
Mark