fuelcenter

Build a minute-by-minute race or long-run fueling plan. Returns target carbs/hour, gel count, gel timing schedule, and total carbs. This is the core FuelCenter tool.

{
  "type": "object",
  "properties": {
    "hours": {
      "type": "number",
      "description": "Race or run duration, hours portion."
    },
    "minutes": {
      "type": "number",
      "description": "Race or run duration, minutes portion."
    },
    "intensity": {
      "type": "string",
      "enum": [
        "easy",
        "easy_moderate",
        "moderate_hard",
        "race_day"
      ],
      "description": "Effort level."
    },
    "experience": {
      "type": "string",
      "enum": [
        "standard",
        "experienced"
      ],
      "description": "Runner experience with fueling. Default \"standard\"."
    },
    "gelKey": {
      "type": "string",
      "enum": [
        "sis_beta_fuel",
        "maurten_100",
        "maurten_160",
        "precision_pf30",
        "gu_energy",
        "gu_roctane",
        "tailwind",
        "spring_energy",
        "carbs_fuel",
        "neversecond_c30",
        "huma_chia"
      ],
      "description": "Gel product key. See /api/tools/gel-comparison for full catalog."
    },
    "targetCPH": {
      "type": "number",
      "description": "Target carbs per hour. If omitted, default is derived from guideline."
    },
    "drinkMix": {
      "type": "boolean",
      "description": "Whether the runner uses a carbohydrate drink mix. Default false."
    },
    "drinkCarbsTotal": {
      "type": "number",
      "description": "Total grams of carbs from drink mix across the run. Default 0."
    },
    "buffer": {
      "type": "number",
      "description": "Minutes of buffer at start and end where no gel is taken. Default 5."
    }
  },
  "required": [
    "hours",
    "minutes",
    "intensity",
    "gelKey"
  ]
}

Predict your finish time at common distances (5K through 100 miles) from a recent race result using the Riegel formula.

{
  "type": "object",
  "properties": {
    "knownDistanceMiles": {
      "type": "number",
      "description": "Distance of your recent race, in miles."
    },
    "knownTimeSeconds": {
      "type": "number",
      "description": "Finish time for that race, in total seconds."
    },
    "exponent": {
      "type": "number",
      "description": "Riegel exponent. Default 1.06."
    }
  },
  "required": [
    "knownDistanceMiles",
    "knownTimeSeconds"
  ]
}

Given any two of distance, total time, or pace-per-mile, calculate the third. Returns pace per mile, per km, splits, and speed.

{
  "type": "object",
  "properties": {
    "mode": {
      "type": "string",
      "enum": [
        "pace",
        "time",
        "distance"
      ],
      "description": "Which field to solve for."
    },
    "distanceMiles": {
      "type": "number",
      "description": "Required for mode \"pace\" or \"time\"."
    },
    "totalSeconds": {
      "type": "number",
      "description": "Required for mode \"pace\" or \"distance\"."
    },
    "paceSecondsPerMile": {
      "type": "number",
      "description": "Required for mode \"time\" or \"distance\"."
    }
  },
  "required": [
    "mode"
  ]
}

Estimate how temperature and humidity will slow your race pace and change your fluid needs. Returns adjusted pace, slowdown percent, dew point, risk level, and fueling note.

{
  "type": "object",
  "properties": {
    "paceSecondsPerMile": {
      "type": "number",
      "description": "Your goal pace in seconds per mile (cool-weather pace)."
    },
    "distanceMiles": {
      "type": "number",
      "description": "Race distance in miles."
    },
    "tempF": {
      "type": "number",
      "description": "Air temperature at race time in degrees Fahrenheit."
    },
    "humidity": {
      "type": "number",
      "description": "Relative humidity as a percentage, 0-100."
    }
  },
  "required": [
    "paceSecondsPerMile",
    "distanceMiles",
    "tempF",
    "humidity"
  ]
}

Estimate fluid and sodium needs for a race or long run based on body weight, duration, intensity, temperature, and humidity.

{
  "type": "object",
  "properties": {
    "bodyWeightLbs": {
      "type": "number",
      "description": "Body weight in pounds."
    },
    "durationMinutes": {
      "type": "number",
      "description": "Run or race duration in minutes."
    },
    "intensity": {
      "type": "string",
      "enum": [
        "easy",
        "moderate",
        "hard",
        "race"
      ],
      "description": "Effort level."
    },
    "tempF": {
      "type": "number",
      "description": "Temperature in Fahrenheit."
    },
    "humidity": {
      "type": "number",
      "description": "Relative humidity, 0-100."
    }
  },
  "required": [
    "bodyWeightLbs",
    "durationMinutes",
    "intensity",
    "tempF",
    "humidity"
  ]
}

Calculate pre-race carb loading targets by race type, body weight, finish time, and experience level. Returns daily carb target, protocol length, total carbs, and pre-race meal size.

{
  "type": "object",
  "properties": {
    "bodyWeightLbs": {
      "type": "number",
      "description": "Body weight in pounds."
    },
    "raceType": {
      "type": "string",
      "enum": [
        "half",
        "marathon",
        "ultra"
      ],
      "description": "Race distance category."
    },
    "finishTimeHours": {
      "type": "number",
      "description": "Expected finish time, hours portion."
    },
    "finishTimeMinutes": {
      "type": "number",
      "description": "Expected finish time, minutes portion."
    },
    "experience": {
      "type": "string",
      "enum": [
        "first_timer",
        "intermediate",
        "experienced",
        "elite"
      ],
      "description": "Runner experience level."
    },
    "hasGIIssues": {
      "type": "boolean",
      "description": "Whether the runner has a sensitive stomach. Default false."
    }
  },
  "required": [
    "bodyWeightLbs",
    "raceType",
    "finishTimeHours",
    "finishTimeMinutes",
    "experience"
  ]
}

Return the FuelCenter gel catalog (SiS Beta Fuel, Maurten, Precision, GU, Tailwind, Spring, Carbs Fuel, neversecond, Huma) with carbs, price, caffeine, weight, and carbs-per-dollar. Optionally sort.

{
  "type": "object",
  "properties": {
    "sortKey": {
      "type": "string",
      "enum": [
        "carbsPerDollar",
        "carbs",
        "priceUsd",
        "weightG",
        "caffeineMg"
      ],
      "description": "Column to sort by. Default \"carbsPerDollar\"."
    },
    "sortDirection": {
      "type": "string",
      "enum": [
        "asc",
        "desc"
      ],
      "description": "Sort direction. Default \"desc\"."
    }
  }
}