Inner-workings of the REBO Hydration Algorithm

REBO’s hydration algorithm starts with scientific evidence and builds on it! 

Let’s start with averages. Scientific research and data estimate that the average adult male needs ~2.5L of water each day. Comparatively, the average adult female requires ~2.0L. Studies further show that 70-80% of the hydration should come from the fluids we drink, leaving 20-30% to be absorbed in the foods we eat. As if it was that simple! We could just do the math and recommend everyone drink the same amount of water each day. Taking into account each individual body constitution and needs - come on, we are all different - our team of hydration experts built upon this data and came up with a hydration algorithm.

Different bodies, different needs

The amount of water your body needs is unique to you. It depends on factors such as your height, weight, gender, activity, and lifestyle.

Maybe you’re an athlete committed to running ten miles every day, come rain or come shine. The amount of water your body needs to replace sweat will be different from someone whose daily release comes from a yin-yoga and meditation practice.

Or, perhaps you’re a new mom. Your birthing and breastfeeding chapters of life will cause you to have totally different hydration needs than your life before baby!

You get the idea. Not only does everyone have different hydration needs, but those needs change overtime. 

Staying hydrated with REBO: Water intake goals custom to your needs

Starting with averages as a baseline, REBO’s hydration algorithm factors in your biometric data and how it impacts your hydration needs. The scientific algorithm looks at your age, weight, height, gender, and activity levels.

Activity levels range from 1-5 and are based on findings from Harvard Medical School. Consider the following Activity Level table when setting up your REBO Hydration Tracker.

Activity Level 1

Calories Burned
Up to 400 calories burned

Daily Example
No significant physical activity

Activity Level 2

Calories Burned
400 to 650 calories burned

Daily Example
30 minutes of non professional basketball

Activity Level 3

Calories Burned
650 - 900 calories burned

Daily Example
30 minutes of bike riding + additional walking/stretching throughout the day

Activity Level 4

Calories Burned
900 - 1,150 calories burned

Daily Example
60 minutes running + 45 minutes of stretching/yoga

Activity Level 5

Calories Burned
> 1,150 calories burned

Daily Example
90 minutes of active swimming

Recognizing all the factors, the algorithm is sensitive to changes. Connecting Apple Health, Google Fit or adidas Runtastic allows you to dynamically adjust your plan based on your daily activity

Did you know that the human brain is 73% water? Anyone who’s seen the 1996 Hollywood classic, Jerry Mcguire, starring Tom Cruise, Renée Zellweger and Cuba Gooding Jr. knows that the human head weighs 8lbs. But did you know that 8lb head is full of water weight? 73% of the human brain is water, and that’s not even the wettest of our organs. Our lungs contain 83% water.

Where does water go in the body?

In addition to ensuring we’re not thirsty, constipated, or tired, the water we drink is literally giving life to our vital organs. Our lungs are made up of a whopping 83% water, followed by our kidneys and muscles each containing 79% water. Our brain and heart each contain 73% water, our liver 71%, our skin contains 64% and our bones-- even they are made up of 31% water.

Let’s now assume we are healthy with optimally hydrated organs. Our bodies would experience water outputs that are approximately equal to our inputs. That would look like something this:

Estimated Daily Water Inputs to the body

  • 70-80% in fluids consumed
  • 20-30% in foods
  • 100% (~2/2.5L)

Estimated Daily Water Outputs from the body

  • 60% Urine
  • 18% Sweat
  • 14% Breathing
  • 8% Faeces
  • 100% (~2/2.5L)

Think about it like our monthly budget or bank account. We have different needs and expenses that require the same thing: money! When we get paid, that paycheck gets divided up to pay things like. Your housing, groceries, gym membership, gifts you buy for yourself and others … but what happens when we overspend? Maybe we have savings in reserve somewhere, but rarely is living on savings long-term sustainable.

It’s the same with water. We need to drink enough, each day, to meet our body’s needs.

If we are not healthy and hydrated, but instead some degree of dehydrated, the inputs and outputs wouldn’t balance and you risk essential organs not getting the life support they need.

Benefits of Hydration