Photo has been used for illustrative purposes.

Mariecar Jara-Puyod, Senior Reporter

The best way to hydrate is “drink to thirst” since the worst in over-consuming water is coma while dehydration in extreme cases leads to death. “However, if the conditions are hot and (one is) planning to exercise for prolonged periods, I would recommend (the consumption of) approximately 250 millilitres of water before exercise, which is about the most the stomach can tolerate and absorb in the period just before exercise,” said Dr Chad Asplund.

Asplund is the Mayo Clinic Orthopaedics and Sports Medicine (Minneapolis, Minnesota, USA)-Underperforming Athlete Clinic director referred to Gulf Today; as the American non-profit academic medical centre which has presence in 19 countries including the UAE through the Greenfield hospital development (for advisory services) and the Sheikh Shakhbout Medical City (a joint venture) in Abu Dhabi, recently released two sets of “Q and As” on “Safety Tips for Hot Weather Exercise” and “What to Drink to Stay Hydrated.”

Asplund was asked about the worse to worst outcomes if one fails to “drink to thirst” or neglect drinking water because in a corresponding video his colleague, Dr Sara Filmalter, a family physician, explained what “drink to thirst” is.

She said: “You can become dehydrated if you take in too little and you can actually cause problems, such as exercise-induced low sodium or Hyponatremia, if you take in so much. So the general rule of thumb at this point among physicians is to drink to thirst. Drink when thirsty.”

The signs and symptoms of Hyponatremia range from “nausea, headache, decrease in energy, muscle cramps, mental confusion, seizures, or coma,” according to Asplund.

“That is why it is important to consume the appropriate amount and type of fluid for the environmental conditions, exercise intensity and duration, and personal tolerance,” continued the Family Medicine & Orthopaedics professor.

He pointed out that Hyponatremia usually occurs at “marathon running events wherein finishers are on the course for more than four hours and consume free water (with less amount of electrolytes such as sodium than the normal human body) of two cups at every aid station, which is the prescribed manner rather than allowing their thirst to guide their intake.”

Asplund said dehydration manifests by way of the decreased or decreasing level of exercise activity and athlete performance.

“But as dehydration worsens, the body’s ability to regulate temperature decreases leading to possible heat injury,” he added.

Apart from heat injury, the negative effects of dehydration are injuries to the kidney and grastrointestinal system.