The televised high-intensity fitness class environment creates a unique curiosity for viewers at home. Instructors on the Peloton platform perform demanding physical activity while simultaneously leading a class and providing constant vocal motivation. The continuous talking combined with the strenuous exercise, often lasting between 30 and 60 minutes, means instructors must maintain an optimal level of hydration to sustain their performance. Viewers often observe the trainers frequently reaching for their water bottles throughout the workout. Understanding what exactly is in those bottles is a common question, as the liquid is clearly more than just a simple thirst quencher.
The Standard Choice: Water and Electrolyte Mixes
The primary liquid consumed by instructors during class is almost always water, but it is typically enhanced with some form of supplement. Simple, unflavored water alone is generally insufficient to replace the nutrients lost during a high-output session. The most common addition is a clear or lightly colored electrolyte mix, which comes in the form of tablets or powders that dissolve into the water. These supplements are formulated to replenish the key minerals, such as sodium and potassium, that are expelled through sweat during intense exercise. For workouts exceeding an hour or those involving high intensity, a carbohydrate-electrolyte drink may be necessary to restore fluid balance and provide energy.
Instructor Personalization and Brand Visibility
While the base fluid is a water-based electrolyte solution, instructors have a degree of freedom regarding the specific brand and flavor they choose. This personalization often leads to the variety of colored liquids viewers see on their screens. Many of the powders or tablets, such as those from Nuun or DripDrop, create brightly tinted drinks, which can be seen in the transparent squeeze bottles used by instructors. The choice of supplement can sometimes be influenced by brand partnerships, as several instructors have publicly collaborated with hydration and nutrition companies. For example, Kirsten Ferguson has partnered with DripDrop, and Jess Sims launched a collaboration with ROAR Organic for an electrolyte-packed powder.
The Science of Mid-Workout Hydration
The constant sipping during a high-intensity class is a physiological necessity driven by the demands of the workout. Intense exercise and the resulting elevated heart rate cause the body to sweat heavily, which is the body’s primary method of thermoregulation. Sweat is hypotonic, meaning it contains a lower concentration of dissolved solutes than the body’s internal fluids, leading to a loss of both water and electrolytes. The continuous vocalizing required of instructors exacerbates fluid loss through respiration, increasing the risk of dehydration. A fluid loss of even two percent of body weight can impair physical performance and increase the risk of fatigue. Electrolyte replacement is crucial for maintaining nerve and muscle function, which prevents issues like cramping and allows the instructor to sustain peak output.