Convert training prescriptions to Intervals.icu workouts with Claude Opus AI
Description
Transform training prescriptions into perfectly formatted Intervals.icu workouts using AI. This workflow automatically converts free-text workout descriptions into structured interval training sessions with proper heart rate zones, pace calculations, and exercise formatting.
What this workflow does
Collects workout details via a web form (date, title, and workout description)
Fetches athlete data from Intervals.icu (FTP, max HR, threshold pace, LTHR)
Processes with AI using Claude Opus 4.1 to intelligently parse and format the workout
Auto-detects workout type (Run, Ride, Strength, HYROX, CrossFit, etc.)
Converts training zones - RPE → HR%, pace calculations, power zones
Formats workout structure with proper transitions, rest periods, circuit formatting
Creates the workout in Intervals.icu via API
Use cases
Coaches: Convert training plans from documents/spreadsheets into Intervals.icu format
Athletes: Quickly add structured workouts from coaching apps or training programs
Hybrid training: Handle complex HYROX, CrossFit, or multi-sport sessions with circuit formatting
Time savings: Eliminate manual workout entry and zone calculations
Supported workout types
Running, cycling, swimming, strength training, HYROX, CrossFit, indoor rowing, virtual training (Zwift), triathlon, and more.
Key features
✅ Intelligent workout type detection
✅ Automatic RPE to HR zone conversion using athlete-specific data
✅ Proper formatting for intervals, circuits, supersets, and progressions
✅ Adds transitions between exercises/machines
✅ Calculates exercise durations and pacing
✅ Handles warmup/cooldown sections
✅ Generates unique workout IDs
Setup requirements
Intervals.icu account with API access (API key required)
Anthropic API key for Claude AI
Athlete must have training zones configured in Intervals.icu (FTP, max HR, LTHR, threshold pace)
Setup instructions
Getting your Intervals.icu API key
Log in to Intervals.icu
Go to Settings (gear icon) → Developer Settings
Click Generate API Key (or copy your existing key)
Save the API key securely
Configuring credentials in n8n
For Intervals.icu (HTTP Basic Auth):
In n8n, open the GetAthleteInfo or CreateWorkoutAPI node
Click on Credentials → Create New Credential
Select HTTP Basic Auth
Enter:
Username: APIKEY (literally type "APIKEY")
Password: Your actual API key from Intervals.icu
Click Save
Apply this credential to both HTTP Request nodes
For Anthropic:
Open the Anthropic Chat Model node
Click on Credentials → Create New Credential
Enter your Anthropic API key
Click Save
Important: The Intervals.icu API uses HTTP Basic Authentication where the username is always the literal string "API_KEY" and the password is your actual API key.
How it works
The workflow uses a sophisticated AI agent with a detailed system prompt that understands training terminology, zones, and Intervals.icu formatting requirements. It applies sport-specific rules to ensure workouts are properly structured for tracking during training sessions.
By Martijn Kerver