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Respiratory Quotient API

Estimate substrate use from exercise intensity and metabolic state.

Endpoint

  • GET /api/v1/fitness/respiratory-quotient
  • POST /api/v1/fitness/respiratory-quotient/post

Parameters

Name Type Required In Description
vo2max_percent number Yes Query/Body Exercise intensity as percent of VO2max.
metabolic_state string No Query/Body fed or fasted; defaults to fed.
lang string No Query Response language (en,fr,es,de,pt,ja,hi,ar,bn,gu,id,it,ko,mr,nl,pa,pl,ro,ru,ta,te,th,tr,ur,vi,zh).

Request Example

curl -X GET "https://api.hefitapi.com/api/v1/fitness/respiratory-quotient?vo2max_percent=68&metabolic_state=fasted&lang=en" \
  -H "X-API-Key: YOUR_API_KEY"

Response Example

{
  "vo2max_percent": 68.0,
  "metabolic_state": "fasted",
  "respiratory_quotient": 0.85,
  "carbohydrate_utilization_percent": 50.0,
  "fat_utilization_percent": 50.0,
  "fuel_mix_label": "Mixed fuel utilization",
  "summary": "Fuel utilization is balanced between carbohydrate and fat.",
  "recommendations": [],
  "language": "en",
  "_api_metadata_": {"endpoint_name": "respiratory_quotient", "response_language": "en"}
}

Localization

This endpoint reads health_fitness_respiratory_quotient.json from the supported language catalogs.