Hydration for The Giro d'Italia

At Saturday, our dedication to improving athletic performance through sports nutrition remains undeterred. This write-up emphasizes the importance of hydration during training, covering vital components such as fluid intake, the role of sodium, and their combined effect on performance. For cyclists competing in the Giro d'Italia, creating and sustaining the correct hydration balance is crucial for achieving optimal performance.

Impact of Dehydration on Performance 

A slight decrease in hydration, approximately 2%, can lead to a reduction in cardiac output - the amount of blood the heart pumps each minute. This decrease requires the heart to work harder to circulate blood, which can lead to a decrease in performance.

As the severity of dehydration increases, there may also be a decrease in muscle power. This is associated with a reduction in blood volume, which impairs the efficient transport of nutrients and oxygen to the muscles. Furthermore, as the body loses more fluids, its ability to control temperature via sweating is impaired. This can lead to an increase in the body's core temperature, causing further negative effects on performance.

Maintaining Hydration and Sodium Levels

Managing fluid and sodium levels effectively during physical activity is of paramount importance. While dehydration is a significant risk, overhydration without sufficient salt intake can result in hyponatremia, characterized by a low concentration of sodium in the blood plasma. Interestingly, the symptoms of hyponatremia, which include headaches, confusion, fatigue, and muscle weakness, are similar to those of dehydration.

To keep the right sodium levels in the blood, consuming a hypotonic solution during training is advisable. However, athletes often fail to take in enough, and a hypertonic solution may be needed to offset the sodium lost through sweat.

Fluid Intake Rates and Concentrations

Most athletes can comfortably consume between 0.8-1.5L of fluid per hour of exercise without causing gastrointestinal problems, as long as the concentration of sugars and electrolytes in the fluid doesn't deviate too much from that of body fluids (concentrations of 10-14% are generally suitable). During shorter bouts of exercise, less than three hours, consuming highly concentrated carbohydrate solutions can be beneficial, as the demand for carbohydrate energy exceeds that for ideal water replacement.

Personalizing Electrolyte Intake

Tailoring electrolyte intake to individual needs during training is vital. Sodium requirements generally range between 500-1500mg/L and depend on factors such as sweat rate, sweat composition, temperature, and humidity. As a general principle, if you sweat more, you're likely to need to consume more sodium per liter to counteract sweat losses.

Options for Sodium Replenishment

There's a wide variety of options for sodium replenishment, from sports drinks to gels and tablets. However, a more budget-friendly choice is basic table salt. Sodium citrate is another effective choice, providing a greater number of sodium ions compared to table salt. Sodium citrate breaks down into three sodium ions and a citrate ion, whereas table salt breaks down into a sodium ion and a chloride ion. This makes sodium citrate a more concentrated source of sodium and puts less stress on the gastrointestinal tract.

Conclusion

For Giro d'Italia cyclists, efficient hydration is central to achieving top performance. Balancing hydration and sodium levels to prevent dehydration and hyponatremia is critical. Adjust your fluid and electrolyte intake to match your unique physiological needs and environmental conditions. Recognizing and addressing your individual needs is key to a successful hydration strategy.