Updated: Jan 14, 2019
Correct nutrition can increase your acute performance, reduce the onset of fatigue and improve health. It can increase your adaptations from training sessions, recovery times, and minimise injury and illness (reduction of missed sessions). However, the wrong personal nutrition can cause 100% failure in the form of a "did not finish" examples of this can be hyponatremia or severe exercise-induced gastrointestinal distress.
Common in endurance athletes - with a higher prevalence in long distance impact based events (running - elite marathon and triathlon), there are various "red flags" that can be adjusted to minimise the onset of symptoms and maximise performance.