from the January issue of Runner's World

Runners know it’s important to stay hydrated to run their best, especially in the summer. “Being more than two per cent dehydrated in warm environments causes a decline in performance,” says Robert W. Kenefick, Ph.D., a physiologist with the Research Institute of Environmental Medicine. To keep fluids handy, you probably stash a water bottle in a gym bag or leave sports drink in your car. But to really improve performance, you need to be more than a casual sipper. A number of recent studies offer runners smarter ways to stay hydrated while also giving their running a boost. Here’s how you can apply some of these strategies to your own hydration plan and run your best all summer long.

GO COLD FOR LONGER RUNS
WHY In a study published in 2008 in Medicine & Science in Sports & Exercise, cyclists who drank cold beverages before and during their workout exercised nearly 12 minutes longer than those who drank warm beverages. And in a study published this year, runners who had an ice slushy ran about 10 minutes longer than when they had a cold drink. In both cases, the drink that was colder lowered body temperature and perceived effort, allowing participants to exercise longer.

DRINK UP Before going for a hot run, have a slushy made with crushed ice and your favourite sports drink. To keep drinks chilled while you run, fill a bottle halfway, freeze it, and top it off with fluid before starting. Running a loop? Stash bottles in a cooler along your route.

STAY ON SCHEDULE
WHY According to a study in the July 2009 Journal of Sports Sciences, when cyclists recorded their plan for hydrating during workouts, including exact times and amounts, they drank more frequently and consumed more fluid mid-workout than their non-planning peers. “Planning helps people remember how much and when they need to drink,” says lead author Martin Hagger, Ph.D., of the University of Nottingham in the United Kingdom.

DRINK UP Note your thirst during your runs, and write down how often and how much you drink. Review your notes to help you plan when to drink. Set your watch to beep every 15 minutes as a reminder to consider your thirst. Drinking smaller amounts at regular intervals can help you absorb fluid more effectively and avoid stomach sloshing.