in the 30-60 minutes before training to ensure that you’re properly hydrated before you start. Once you’re running, sip 150-200ml every 15 minutes. If you’re still thirsty afterwards, or failed to drink during the session, another 400-800ml may be required.—Joe

‘scared’, and not keeping track of your intake. Next time, drink only fluid-replacement drinks (about 600-750ml per hour) and not water. And practise drinking these amounts in your pre-race training runs. —Joe Beer, sports scientist and level-two triathlon

foods to ensure adequate mineral intake. Also do not completely eliminate salty foods from your diet. These will help to ensure you have adequate electrolytes to balance fluid losses each day.—Joe Beer, sports scientist and level two triathlon coach