Endurance Cycling and the Risk of Water Intoxication

Water, confusion, nausea, fatigue, and seizures during cycling events can be quickly dismissed as symptoms of dehydration. These are not just symptoms of dehydration. They are also the symptoms of dilutional hyponatremia. Dilutional hyponatremia, or water “intoxication” occurs when an athlete drinks too much electrolyte-free water. This is any type of water lacking salt or other forms of sodium. During prolonged exercise, a person will lose up to 4 liters of sweat per hour. Every four liters, the body looses .20 liters of sodium. This appears to be an insignificant amount of sodium, but high levels of fluid replacement without sodium completely washes out the correct blood/sodium concentration.

When you intake an extra sip of water with the intention of feeling better, it may be depleting instead of replenishing. Hyponatremia is more common in physical exertion lasting more than five hours. Therefore, a cyclist is at a higher risk of this condition than other athletes due to the long durations of recreational rides, racing, and especially bicycle touring.
It is problematic more so for slower riders. The slower rider will likely intake greater amounts of fluid than a faster rider who covers the same distance over a much shorter period of time. Cycling at higher speeds leaves less time to concentrate on drinking water.

Yet, this is not to say that riding faster or overexerting yourself is a better alternative. There are sound methods for preventing water intoxication from occurring. If you ever experience mild nausea, unusual fatigue, or abnormal swelling during training, cease doing so until you can discuss the condition with your physician.

Slight swelling of the limbs may occur after riding long distances. Problems with more frequent and severe swelling must be diagnosed since it can be an early warning of edema, kidney and heart diseases. Confusion and seizures, on the other hand, require immediate medical attention.

Otherwise healthy individuals should take the following precautions: Be conscious of the amount of water, especially sodium-free water, you are consuming. When the stomach feels cramped or full, it may be a good time to reduce intake.
Consult a scale during training before and after long-distance sessions. A slight weight gain may indicate that there is too much water intake. The fluid ingested exceeds the urine and sweat losses.

As bizarre as it may seem, keep a journal that records sweat and urine losses over the course of a week. If you wish, record your weight as explained above.

Also, the weather is an important consideration as severe temperatures will require higher rates of sodium replacement. Use this information to try to determine your own appropriate fluid replacement.

If pure water is your die-hard belief, consider to at least alternate between water that has been enhanced with electrolytes. There is an array of electrolyte water available in today’s market without any flavor, sugar, or other artificial ingredients.
A view of the ocean, lake, or river bed is quite enjoyable during a challenging ride. However, don’t drown yourself before you reach the finish line. Balanced fluid replacement is essential for high performance and a thrilling ride.