Fuel is chemistry, and chemistry has units.
Every recovery protocol on this platform assumes you are fed, and most athletes are not. The Desk takes a profile (sport, mass, training block, restrictions) and returns numbers with their arithmetic on the surface: protein in g/kg, carbohydrate periodized to the session, caffeine in mg/kg with a timing window, energy availability against the threshold where hormones start switching off. Ask it anything about fuelling and it answers in mechanism first, the same as the Coach.
Topics
22
Intake rules
5
Equations
9
Data sent out
0req
Your fuel board
Today, in grams and minutes.
Pick the kind of day on the board, or change the profile below, and every number on this page moves with it. Your own body mass is in all of the arithmetic.
Energy, practice day
2,894kcal
Energy availability 46 kcal/kg lean mass. The floor is 30; this plan never goes under 45.
Protein
122g1.9 g/kg
Carbohydrate
448g7.0 g/kg
Fat
68g1.1 g/kg
Fluid baseline
3.3 L
Your day
caffeine cutoff 14:00
- 07:00BreakfastP 21 · C 63 g
- 12:30LunchP 23 · C 69 g
- 14:30Pre-session top-upP 6 · C 51 g
- 15:30During volleyball practiceC 110 g
- 17:30RecoveryP 19 · C 64 g
- 18:45DinnerP 26 · C 78 g
- 21:30Before bedP 26 · C 13 g
Tell it who is eating, once.
Every target below is a function of these inputs and nothing else. Move a slider and the numbers on the right recompute; set it once and this browser remembers it, so the plan is still yours next week.
Education, not diagnosis. This is a science education platform. Nothing here replaces a physician, a physical therapist, or an athletic trainer. Sudden severe pain, numbness, an inability to bear weight, or visible deformity means stop reading and get seen.
64kg
173cm
17years
0not set
Leave at zero if unmeasured. A guess here is worse than the population default.
6sessions
110min
Sport
Training block
Match load plus practice load. This is where under-fuelling usually starts.
Goal
Energy availability is the objective. No deficit.
Dietary constraints
Answers pick up substitutions that name the nutrient at risk, not just the food.
Sex assigned at birth
Used for the lean-mass default and the iron note.
22:00
Sets the caffeine cutoff, working back one half-life at a time.
Energy availability
46kcal/kg FFM
Fully funded. Physiology is not being asked to economise.
Energy, average day
2810kcal
Protein
102–141g
Carbohydrate
384–512g
Fat
59g
Per meal protein
19g × 4
Fluid baseline
3.3L
Caffeine band
192–384mg
Caffeine cutoff
14:00
Creatine
3.0g/day
These are averages across your training week. The plan below moves them day by day: more carbohydrate on a match day, less on a rest day, protein steady. Ask the Desk for any of them by name and it returns the equation and the reason it was chosen.
From grams to an actual day of food
A daily total is not something you can eat. This turns it into a timetable around your wake, practice, and bed times, with example meals in ordinary foods that respect every dietary constraint on your profile, then the same day as a plate, a week, and a shopping list.
The default. Carbohydrate tracks the training block you set in the profile.
06:30
15:30
22:00
- 07:00
Breakfast
P 21 gC 63 gF 18 g499 kcal- 150 g Greek yoghurt
- 80 g rolled oats (dry)
- 1½ tbsp peanut butter
Example adds up to P 30 gC 65 gF 19 gLiver glycogen runs down overnight to roughly half. Breakfast refills it and delivers the first leucine bolus of the day.
- 12:30
Lunch
P 23 gC 69 gF 20 g549 kcal- 1 cup cooked lentils
- ¾ cup cooked quinoa
- 2 cups vegetables
- 30 g pumpkin seeds
Example adds up to P 36 gC 83 gF 18 gThe meal most often skipped at school and the one an afternoon practice runs on. Glycogen eaten at lunch is glycogen available at 4pm.
- 14:30
Pre-session top-up
P 6 gC 51 gF 2 g248 kcal- 50 g Greek yoghurt
- 1 plain bagel
Example adds up to P 15 gC 55 gF 2 g320 mL fluidFast carbohydrate, low fibre, low fat, so it leaves the stomach before the warm-up does. Tops up blood glucose without a gut in the way.
- 15:30
During volleyball practice
C 110 g440 kcal- 1000 mL sports drink
- 2 energy gels
Example adds up to C 118 g1056 mL fluidPast about an hour, exogenous carbohydrate spares muscle glycogen and keeps the central governor supplied. Sip to the hourly rate rather than all at once.
- 17:30
Recovery
P 19 gC 64 gF 3 g362 kcal- ½ scoop whey isolate
- 630 mL orange juice
Example adds up to P 18 gC 66 gGLUT4 sits at the membrane for about an hour after work, insulin-independent. Carbohydrate plus a protein dose here is the cheapest glycogen of the day.
- 18:45
Dinner
P 26 gC 78 gF 22 g615 kcal- 60 g chicken breast (cooked)
- 2 cups cooked pasta
- 2 cups vegetables
- 1½ tbsp olive oil
Example adds up to P 38 gC 96 gF 25 gThe largest meal is the one with the longest runway: most glycogen resynthesis and tissue repair happens overnight.
- 21:30
Before bed
P 26 gC 13 gF 3 g182 kcal- ¾ scoop soy or pea-rice protein
Example adds up to P 17 gC 2 gF 2 gA slow protein holds blood amino acids through roughly seven fasted hours of overnight repair. Optional, and smaller than it sounds in importance.
Ask it the way you would ask a teammate
Supplements, timing, diets, or your own numbers. Every message passes the intake screen before anything is computed, and the answers read the same profile as the plan.
Ask it the way you would ask a teammate.
“Is pre-workout worth it” works better than trying to phrase it like a textbook. The profile you set above rides along with every question, so answers come back with your own body mass in the arithmetic instead of a table of averages. Every message passes an intake screen before any number is computed.
About my numbers
Plan my day
Pre-workout and supplements
Fuelling around sessions
Diets and patterns
Answers read the profile · Enter sends
The profile is kept in this browser so you do not have to re-enter a body mass every visit, and the transcript is kept for this tab only. Nothing you type or measure is transmitted, stored on a server, or used to train anything.
Questionnaires, sources, and a page for the fridge.
Six private self-audits that screen for warning signs before they score anything, and a library of the position stands, fact sheets, and databases every number on this page comes from.
Answers never leave this browserSix questionnaires
Audit the habits before you trust the numbers
Fuelling, hydration, tournament readiness, sleep and caffeine, supplements, and an energy-availability screen adapted from the LEAF-Q. Each screens for warning signs first and refers to a person when it should.
29 verified sourcesResource library
The primary sources, and the people to call
The IOC, ACSM, and ISSN position stands behind every equation, the USOPC fact sheets, third-party supplement databases, a sports-dietitian finder, and confidential support.
One-page cheat sheetNine equations, each with a name on it
A number you cannot audit is a number you should not act on. These are the equations behind every figure the Desk returns, the paper each came from, and why it was chosen over the obvious alternative.
Resting metabolic rate
Cunningham, 1980
RMR = 500 + 22 × FFM
Driven by fat-free mass rather than by scale weight. Mifflin-St Jeor is the common alternative and under-predicts in lean, trained people by roughly 5 to 10 percent, which is precisely this population.
Exercise energy expenditure
Ainsworth Compendium, 2011
EEE = (MET − 1) × kg × hours
One MET is subtracted because resting burn is already counted in RMR. Skipping that subtraction is the single most common way an online calculator over-feeds by a few hundred kilocalories a day.
Energy availability
Loucks 2003 · IOC REDs consensus 2023
EA = (intake − EEE) ÷ FFM
The number that governs whether the endocrine system stays funded. Below 30 kcal/kg FFM per day, luteinising hormone pulsatility and bone formation markers both move within about five days.
Protein
Morton 2018 · Moore 2015
1.6–2.2 g/kg/day · 0.3 g/kg per feed
1.62 g/kg is the meta-regression breakpoint for resistance-trained gains. The per-feed dose exists because synthesis is a saturable response to a leucine bolus, not to a daily total.
Carbohydrate
ACSM / AND / DC position stand, 2016
3–10 g/kg/day, periodized to the session
Banded by the day in front of you rather than fixed, because glycogen demand on a rest day and a tournament day genuinely differ by a factor of two.
Carbohydrate during exercise
Jeukendrup, 2010
30 → 60 → 90 g/h, 2:1 glucose:fructose at the top
SGLT1 saturates near 60 g/h. Fructose recruits GLUT5 as a second transporter, which is the only reason the 90 g/h ceiling exists at all.
Caffeine
ISSN position stand, Guest 2021
3–6 mg/kg, 45–60 min before · cutoff 8 h before bed
Dosed to mass because the effect is a receptor-occupancy question. The cutoff comes from a half-life near five hours, so an afternoon dose is still meaningfully present at midnight.
Creatine
ISSN position stand, Kreider 2017
0.03 g/kg/day maintenance · 0.3 g/kg/day load
Both routes reach the same muscle saturation. Loading arrives in a week instead of four, at the price of more gastrointestinal complaints.
Fluid replacement
ACSM position stand, Sawka 2007
125–150% of the mass deficit, with sodium
More than 100 percent because some of any plain water consumed is simply urinated out. Sodium is what makes the rest of it stay.
The screen that runs before the calculator
Nutrition questions from teenage athletes overlap with disordered eating far more often than injury questions overlap with emergencies. A calculator that cheerfully returns a deficit to someone describing restriction is not a neutral tool.
Screen 01 · runs before any arithmetic
5 rulesRestriction and compensation language
Language describing restriction, compensation, or food guilt is the most common early presentation of a serious and treatable condition, and it is more common in athletes than in the general population.
Talk to a physician, a registered sports dietitian, or someone you trust this week. In the US, the National Alliance for Eating Disorders helpline is 1-866-662-1235.
Compensatory behaviour
These behaviours carry immediate medical risk, including electrolyte disturbance and cardiac arrhythmia, entirely separate from their psychological weight.
This needs a physician now, not a nutrition plan. If you are in the US, the National Alliance for Eating Disorders helpline is 1-866-662-1235.
Rapid weight cut
Acute dehydration cuts reduce plasma volume and thermoregulatory capacity, and have caused deaths in scholastic sport. There is no version of this that is safe to self-administer as a minor.
This has to go through your team physician and coaching staff, with a supervised protocol. The Desk will not produce one.
Missed periods
Menstrual disruption in a training athlete is a clinical sign, most often of low energy availability, and it carries bone density consequences that are only partly reversible.
See a physician. Bring a week of honest food and training logs, because that conversation goes much faster with data.
Condition needing individual medical nutrition therapy
These conditions change the arithmetic fundamentally and require individualised medical nutrition therapy from a registered dietitian working with your physician.
Ask for a referral to a registered dietitian who works with athletes and knows your condition.
These rules are deliberately over-sensitive, and they will sometimes stop a question that was perfectly innocent. That trade is the correct one: the cost of a false positive is one rephrased sentence, and the cost of a false negative is a calculator handing a deficit to someone who needed a conversation.
The refusals are the feature
The interesting half of any health-adjacent tool is the list it will not touch. This one will not produce a weigh-in cut, will not return a target under the energy-availability floor, and will not diagnose a deficiency that needs a blood test.
What it does
Computes daily energy, protein, carbohydrate, fat, fluid, caffeine, and creatine targets from your own body mass and training load.
Shows the arithmetic for every number, including which equation it used and what it assumed.
Calculates energy availability, the threshold most calculators never mention.
Grades the evidence honestly, and publishes the supplements that fail.
Adjusts substitutions for vegetarian, vegan, dairy-free, gluten-free, nut allergy, halal, and kosher constraints.
What it will not do
Diagnose anything, including a deficiency. Iron and vitamin D need a blood test, not a chatbot.
Produce rapid weight-cut or weigh-in protocols. Ever.
Return a calorie target below the energy availability threshold, whatever the goal setting says.
Give medical nutrition therapy for diabetes, coeliac disease, IBD, kidney disease, an eating disorder, or pregnancy.
Send anything anywhere. The whole engine runs on this device.
What it actually knows
Grouped by what the nutrient is doing rather than by the aisle it sits in, because caffeine and creatine have nothing in common except a shelf.
Energy
01
Energy availability and RED-S
Macronutrient
02
How much protein you actually need
Carbohydrate, periodized
Timing
04
The anabolic window
Fuelling during the session
Recovery nutrition
The pre-game meal
Ergogenic
06
Caffeine
Creatine monohydrate
BCAAs
Beetroot and dietary nitrate
Collagen and vitamin C for tendon
Protein powder, choosing one
Micronutrient
03
Iron and ferritin
Vitamin D
Omega-3 fatty acids
Hydration
01
Hydration and electrolytes
Pattern
05
Body composition, done without wrecking anything
Vegetarian and vegan athletes
Intermittent fasting for athletes
GI distress and gut training
Eating for sleep
Education, not diagnosis. This is a science education platform. Nothing here replaces a physician, a physical therapist, or an athletic trainer. Sudden severe pain, numbness, an inability to bear weight, or visible deformity means stop reading and get seen.