A meal after hard training holds more fluid in the body than a sports drink alone. The sodium and potassium on the plate do the work.

Cool drinks raise voluntary intake by about half and ice slurry can extend endurance before a hot session, but ice during exercise in dry heat can cut sweating more than it cools. Here is what fluid temperature does and does not do.

A shot of pickle brine can cut a muscle cramp short, but through a reflex in the throat rather than electrolyte replacement. Here is what the research shows and how to dose it.

Independent lab tests show home water filters vary enormously against PFAS, lead and microplastics. The certification number on the box tells you more than the marketing does, and a filter you trust can change how much water you drink.

Eight of the best selling electrolyte mixes, read off their own nutrition panels, spread across an eighteenfold range of sodium. Here is what the numbers mean, what the research says they should be, and how to match a product to your own sweat.

Glycerol came off the WADA Prohibited List on January 1, 2018 and has been legal ever since. The retention numbers are dramatic, the performance numbers are modest, and the difference between the two is where athletes get this wrong.

Fluid loss takes 5.5 percent off strength and 8.3 percent off muscle endurance, and the weight room is the worst place to notice. What the research says, and the forty second weigh-in that measures it.

Caffeine is a diuretic in the textbook sense, and for habitual drinkers at ordinary doses that turns out not to matter. What the controlled trials actually measured, and the two situations where the caution still applies.

A trial designed to separate water from salt found that fluid volume, not sodium, protected performance in the heat. The company that funded it sells sodium.

Races are moving their dates and start times because cool mornings are disappearing. Runners are not moving at all, which is why the heat plan has to be built in August.