Calculate precise heart rate training zones based on age and resting heart rate using established formulas. Access via MCP in Cursor or Windsurf for fitness app development, or call GET /v1/health/heart-rate-zones directly. Returns five zones (recovery, aerobic base, aerobic, lactate threshold, neuromuscular) with BPM ranges and percentages—essential for accurate training data instead of guessed calculations.
curl "https://tinyfn.io/v1/health/heart-rate-zones" \
-H "X-API-Key: YOUR_API_KEY"const response = await fetch('https://tinyfn.io/v1/health/heart-rate-zones', {
headers: { 'X-API-Key': 'YOUR_API_KEY' }
});
const data = await response.json();
console.log(data);import requests
response = requests.get('https://tinyfn.io/v1/health/heart-rate-zones',
headers={'X-API-Key': 'YOUR_API_KEY'})
data = response.json()
print(data)Connect your AI agent (Claude, Cursor, Windsurf, etc.) to TinyFn's health tools:
{
"mcpServers": {
"tinyfn-health": {
"url": "https://tinyfn.io/mcp/health",
"headers": {
"X-API-Key": "YOUR_API_KEY"
}
}
}
}Uses the Karvonen formula: (max HR - resting HR) × intensity percentage + resting HR. Max HR is typically 220 minus age, though the tool may support custom max HR values.
Zone 1: 50-60% (recovery), Zone 2: 60-70% (aerobic base), Zone 3: 70-80% (aerobic), Zone 4: 80-90% (lactate threshold), Zone 5: 90-100% (neuromuscular power).
Yes, integrate it in Cursor or Claude Code for reliable zone calculations. Much better than hardcoding formulas that might have errors—get deterministic results for user training plans.
Age is required for maximum heart rate calculation. Resting heart rate improves accuracy significantly—without it, the tool likely defaults to an average (around 70 BPM).
Returns JSON with zone numbers, names, BPM ranges (min/max), and percentage ranges. Perfect for displaying training targets in fitness applications or wearable integrations.
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