From shade tree mechanics to Formula One engineers, they all understand the balance needed to get the most from their machines. Run it lean — too much air, not enough fuel — and you'll sap power while encouraging overheating and disastrous detonation. Run it rich — too much fuel, not enough air — and you will bog power, fouling internals and wasting resources while losing power. It's the same human body’s engine, where absolute performance is a balance of fuel, hydration, recovery and rehydration. Those physiological mechanisms involved in electrolyte and water turnover during exercise have a real impact on hydration during exercise performance. So just as a mechanic tunes a race car, what are the most effective interventions you take to optimize your body's hydration and rehydration in sport?