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Intro: Hydration is a cornerstone of athletic performance, yet it’s one of the most commonly overlooked aspects of health. Even mild dehydration can cause brain fog, reduce physical performance, and increase injury risk.

In this RB100 Challenge, your goal is simple: Drink 100 ounces (approx. 3 litres) of water in a single day — and feel the difference.


Why 100oz?

  • Supports joint lubrication and muscle elasticity
  • Enhances digestion and nutrient absorption
  • Boosts cognitive function and energy levels
  • Aids temperature regulation during exercise

How Much Is 100oz?

  • Roughly 3 litres or 12 standard glasses of water
  • 2 large refillable bottles (1.5L each)
  • Split across your day in 4–6 servings

How to Make It Happen

  • Start with 500ml immediately upon waking
  • Use a tracker app or smart bottle
  • Add fresh fruit, cucumber, or mint for variety
  • Pair each meal with a full glass
  • Keep a bottle within reach at your desk or gym

Tips for Training Days

  • Add electrolytes if you’re sweating heavily
  • Avoid sugary drinks as hydration substitutes
  • Use your bodyweight (in kg × 0.035) as a hydration baseline

Pair it with:


External Resources:

water is your performance multiplier.

RB100.Fitness
Editorial Team

The Relentless Bravery Editorial Team brings together athletes, coaches, and experts to share trusted insights on training, recovery, and mindset. Always consult a professional before making fitness or health changes.

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