How to Stay Hydrated on Training Days Without a Spreadsheet

Anyone who trains knows the afternoon after a hard morning session: the headache, the heavy legs, the vague sense of being behind on something. Usually it is water. The amount you need on a training day is higher than on a rest day, the morning session makes the gap wider, and nothing in an ordinary day reminds you to close it.

What training does to the number

The National Academies' adequate intake for total water is about 2.7 liters a day for women and 3.7 for men, including the water in food (Dietary Reference Intakes for Water). Those figures are for ordinary days. The American College of Sports Medicine's position stand on fluid replacement puts typical sweat rates during exercise at roughly 0.5 to 2 liters an hour depending on the person, the intensity and the heat, and recommends replacing what you lose over the hours after the session rather than all at once (ACSM, 2007).

So a training day can easily need two to four extra glasses, and the replacing has to happen across the afternoon, which is exactly when nobody is thinking about it.

The plan

1. Set two goals: a rest-day goal and a training-day goal. Eight glasses and eleven is a reasonable starting pair; adjust from how you feel at 4pm.

2. On training days, drink two glasses in the hour before the session and count them.

3. Weigh yourself before and after a hard session a few times if you want your own number. Each pound lost is roughly two cups of water to replace over the following hours.

4. Log every drink as it happens, including during the session. A bottle in the gym bag counts only if it gets counted.

5. Let something check in with you in the afternoon on the days you are behind. That is the gap, and it is the same gap every time.

Where the text check-in fits

Water Textapp keeps the count and handles the goal switch. Text Hi to its number and tell it your rest-day goal. On a training morning, tell it the higher goal in plain words, "11 glasses today" or "make it 3 liters", and it updates. You can switch back the next day the same way, or just leave the higher goal if you train most days.

Each drink is one message: "2", "a bottle", "40 oz", "half a liter". It converts, adds it up and tells you what is left. If you drink from a particular bottle, tell it the size once and "one" means that bottle from then on.

It checks in at 11am and 4pm in your zone, only on days you are short of the goal, and the 4pm one is the one that earns its keep on training days: it arrives in the window the sports-medicine guidance says the replacing should happen, with the number you still owe.

Ask where you stand before a session and it tells you. Ask about your streak and it tells you how many days running you have hit the goal.

What changes after two weeks

The first thing people notice is the afternoon headache going away on training days. The second is that the training-day goal starts to feel normal, because the count makes the extra glasses concrete instead of a vague "drink more". By week two most people have found their own number, a glass or two either side of the starting guess, and the check-in arrives less often because they are already there.

Try it by text

Text Hi to (646) 640-0771 to start Water Textapp. It works on any phone that can text, with no app to install and no account to create. Tell it your goal, raise it on training days, send it a number each time you drink, and let the afternoon check-in close the gap.

Your first 20 messages are free. After that, one $9.99 a month subscription covers every Textapp. Text STOP at any time to end it.