/nutrition — Post-Run Nutrition Analysis

Computes total and per-hour intake of water, carbohydrates, sodium, and caffeine from the athlete's reported fueling, then adds a summary note to the Intervals.icu event.

Step 1: Read knowledge base

Read

knowledge/nutrition.md

to inform the analysis with fueling targets and expert recommendations.

Step 2: Collect inputs

Ask the athlete (if not already provided) for:

• What they consumed — products, quantities, and how they were carried (e.g., "2 gels, 1 waffle, Tailwind in a flask")
• Water volume — total liters carried/consumed, and what was mixed into it (electrolyte tabs, drink mix, etc.)

Also identify the activity. If not specified, fetch the most recent activity from the last 3 days using the activities endpoint. You need the elapsed time (not moving time) to compute per-hour rates, since the athlete fuels during stops too.

Step 3: Look up nutritional data

Use the reference table below for common products. For products not listed, use your best knowledge of the product's nutrition facts — state your assumptions and invite corrections.

Common Products Reference

Gels (~1 oz / 32g packets)

Product	CHO (g)	Sodium (mg)	Caffeine (mg)
Honey Stinger Honey Gel	24	50	0
Honey Stinger Ginsting Gel (caffeinated)	24	60	32
Honey Stinger Salted Caramel Gel (caffeinated)	24	50	32
GU Energy Gel (non-caffeinated)	22	125	0
GU Roctane Gel (caffeinated, varies)	21	125	35
SiS GO Isotonic Gel	22	20	0
SiS GO + Caffeine Gel (Double Espresso, etc.)	22	20	75
Spring Energy Awesome Sauce	45	115	0
Maurten Gel 100	25	30	0
Maurten Gel 100 CAF 100	25	30	100

Waffles / Chews / Bars

Product	CHO (g)	Sodium (mg)	Caffeine (mg)
Honey Stinger Honey Waffle	21	50	0
Honey Stinger Salted Caramel Waffle	21	85	0
GU Energy Chews (1 packet)	34	70	0
Clif Blok (1 packet, 6 chews)	24	70	0
Muir Energy Bar (varies)	28	40	0

Drink Mixes (per serving as labeled)

Product	Serving	CHO (g)	Sodium (mg)	Caffeine (mg)
Tailwind Endurance Fuel	1 scoop (27g)	25	150	0
Tailwind Endurance Fuel (caffeinated)	1 scoop (27g)	25	150	35
Tailwind High Carb	see note	see note	see note	0
Skratch Labs Exercise Mix	1 scoop (22g)	20	190	0
Maurten Drink Mix 320	1 packet (80g)	79	180	0

Tailwind note: Athletes often describe Tailwind by total CHO rather than scoops (e.g., "90g CHO of Tailwind"). To compute sodium: ~150mg per 25g CHO (i.e., multiply CHO grams by 6 to get sodium in mg). Caffeinated flavors add 35mg caffeine per 25g CHO.

Electrolyte Tablets / Capsules (no/minimal calories)

Product	CHO (g)	Sodium (mg)	Caffeine (mg)
Nuun Sport (1 tab / 500mL)	1	300	0
Nuun Energy (1 tab / 500mL)	2	300	40
LMNT (1 packet)	0	1000	0
SaltStick Cap (1 capsule)	0	215	0
Precision Fuel & Hydration PH 1500 (1 tab)	0	500	0

Step 4: Compute totals

Build a table showing each item, its quantity, and its contribution:

| Item | CHO (g) | Sodium (mg) | Caffeine (mg) |
|---|---|---|---|
| [Product] x [qty] | ... | ... | ... |
| ...  | ... | ... | ... |
| **Total** | **XXXg** | **X,XXXmg** | **XXmg** |

Add total water consumed as a separate line.

Step 5: Compute per-hour rates

Divide totals by elapsed time in hours (not moving time — the athlete fuels during stops too).

| Water | Carbs | Sodium | Caffeine |
|---|---|---|---|
| X.X L/hr | XX g/hr | XXX mg/hr | XX mg/hr |

Step 6: Compare to targets

Reference targets from

knowledge/nutrition.md

and the athlete's profile:

Metric	Target Range	Source
Water	0.5-1.0 L/hr (heat/effort dependent)	Athlete profile, conditions
Carbs	60-90 g/hr (trained gut)	Koop: 30-60g, modern research: up to 90g+
Sodium	500-700 mg/hr	Standard electrolyte guidance
Caffeine	0-50 mg/hr (save for back half in ultras)	Strategic use, ~3-6mg/kg total

Flag anything notably above or below target. Note any GI issues the athlete reported. If carbs are above 60g/hr with no GI issues, acknowledge that the gut is well-trained.

Step 7: Add note to Intervals.icu event

Find the matching planned event for the activity date using the events endpoint. Update its description to append a nutrition summary line:

💧 X.XL (X.XL/h) | 🍪 XXg/h | 🧂 XXX mg/h | ☕ XX mg/h

Round values to whole numbers for carbs/sodium/caffeine, one decimal for water. Use the update event endpoint to append this line to the existing description (do not overwrite it — read the current description first and append).

Step 8: Coaching note

Offer one brief observation:

• Is the athlete hitting their targets?
• Any changes to consider for race day?
• Caffeine timing strategy (save for back half of long races)
• Hydration vs conditions (was it hot? did they drink enough?)
• GI tolerance — is the gut trained for this intake rate?