Race day nutrition can unquestionably help you to perform better. If you want to go faster, you should make nutrition a focus... There are no universal rules. Though Usain Bolt is a special case and 100m is a very different discipline to triathlon, he found what suited him as a pre-race meal and stuck to it. Though I wouldn't recommend chicken nuggets to my clients!
It's important to emphasise carbs in the meal and snack before your training session. If you're training in the middle of the day, breakfast should be very substantial. If you're planning an evening training session, you should make lunch the big one.
Creatine: it's a supplement discussed in hushed, foreboding tones around the gym lockers, and rarely mentioned outside of sporting circles, such is its social stigmatisation. It's the sporting world's 'entry drug', give in to the dark side embracing the 'Big C' and you're on the fast track to an obligatory doping scandal.