{
  "id": "heart-rate-zone",
  "version": "0a8dac0cfbe0",
  "status": "published",
  "name": "Heart Rate Zone Calculator",
  "question": "What are my five heart rate zones?",
  "summary": "Works out five heart rate training zones, the ACSM exercise intensity classes, from age (and optionally resting heart rate by the Karvonen method), and which zone a heart rate is in.",
  "category": "health",
  "subcategory": "body",
  "url": "https://www.acalculator.org/health/heart-rate-zone-calculator",
  "markdown": "https://www.acalculator.org/health/heart-rate-zone-calculator.md",
  "kind": "function",
  "method": "Zone start = rest + share × (max − rest), with rest 0 and shares 57%, 64%, 77%, 96% of the maximum, or with the resting heart rate and shares 30%, 40%, 60%, 90% of the reserve (Karvonen); max = 220 − age or 208 − 0.7 × age.",
  "assumptions": [
    "The five zones are the ACSM exercise intensity classes: very light, light, moderate, vigorous, and near maximal to maximal (Garber and others, 2011).",
    "Each zone limit is rounded half up to a whole beat per minute; a zone ends one beat before the next one starts.",
    "The age formulas estimate the maximum heart rate; a measured maximum can differ by 10 beats per minute or more.",
    "Heart-rate medicines such as beta blockers change the response to exercise. This is not medical advice."
  ],
  "inputs": {
    "$schema": "https://json-schema.org/draft/2020-12/schema",
    "type": "object",
    "properties": {
      "age": {
        "title": "Age",
        "description": "Your age in whole years.",
        "type": "integer",
        "minimum": 15,
        "maximum": 100
      },
      "formula": {
        "title": "Maximum heart rate formula",
        "description": "How the maximum heart rate is estimated from age: 220 − age, or 208 − 0.7 × age (Tanaka).",
        "type": "string",
        "enum": [
          "fox",
          "tanaka"
        ]
      },
      "max": {
        "title": "Measured maximum heart rate",
        "description": "Your maximum heart rate from a test, if you know it. It replaces the age estimate.",
        "type": "integer",
        "minimum": 100,
        "maximum": 230
      },
      "rest": {
        "title": "Resting heart rate",
        "description": "Your heart rate at rest, in beats per minute. With it, the zones use the heart rate reserve (Karvonen).",
        "type": "integer",
        "minimum": 30,
        "maximum": 110
      },
      "hr": {
        "title": "Heart rate to check",
        "description": "A heart rate measured during exercise, in beats per minute, to see which zone it is in.",
        "type": "integer",
        "minimum": 30,
        "maximum": 250
      }
    }
  },
  "outputs": {
    "max": {
      "label": "Maximum heart rate",
      "description": "The measured maximum, or the age estimate, in beats per minute.",
      "format": "number"
    },
    "zone1": {
      "label": "Zone 1: Very light",
      "description": "The very light zone in whole beats per minute: from rest to the start of zone 2.",
      "format": "text"
    },
    "zone2": {
      "label": "Zone 2: Light",
      "description": "The light zone in whole beats per minute: 57% to 63% of the maximum, or 30% to 39% of the reserve.",
      "format": "text"
    },
    "zone3": {
      "label": "Zone 3: Moderate",
      "description": "The moderate zone in whole beats per minute: 64% to 76% of the maximum, or 40% to 59% of the reserve.",
      "format": "text"
    },
    "zone4": {
      "label": "Zone 4: Vigorous",
      "description": "The vigorous zone in whole beats per minute: 77% to 95% of the maximum, or 60% to 89% of the reserve.",
      "format": "text"
    },
    "zone5": {
      "label": "Zone 5: Near maximal",
      "description": "The near maximal zone in whole beats per minute: 96% of the maximum or 90% of the reserve, up to the maximum.",
      "format": "text"
    },
    "zoneOf": {
      "label": "Checked heart rate is in",
      "description": "The zone of the heart rate to check, from the whole-number zone limits above.",
      "format": "text"
    },
    "method": {
      "label": "Zones based on",
      "description": "Shares of the maximum heart rate, or of the heart rate reserve when a resting heart rate is given.",
      "format": "text"
    }
  },
  "defaultAnswer": {
    "inputs": {
      "age": 35,
      "formula": "fox"
    },
    "outputs": {
      "max": 185,
      "zone1": "Below 105 bpm",
      "zone2": "105 to 117 bpm",
      "zone3": "118 to 141 bpm",
      "zone4": "142 to 177 bpm",
      "zone5": "178 to 185 bpm",
      "method": "Maximum heart rate"
    },
    "text": "With a maximum heart rate of 185 bpm, zone 2 (light) is 105 to 117 bpm and zone 3 (moderate) is 118 to 141 bpm."
  },
  "examples": [
    {
      "given": {
        "age": 30,
        "formula": "fox"
      },
      "expect": {
        "max": 190,
        "zone1": "Below 108 bpm",
        "zone2": "108 to 121 bpm",
        "zone3": "122 to 145 bpm",
        "zone4": "146 to 181 bpm",
        "zone5": "182 to 190 bpm"
      },
      "source": "ACSM intensity classes (Garber 2011, Table 4): 190 × 0.57 = 108.3, × 0.64 = 121.6, × 0.77 = 146.3, × 0.96 = 182.4; hand calculation in content.mdx"
    },
    {
      "given": {
        "age": 40,
        "formula": "fox",
        "rest": 60,
        "hr": 130
      },
      "expect": {
        "max": 180,
        "zone1": "60 to 95 bpm",
        "zone2": "96 to 107 bpm",
        "zone3": "108 to 131 bpm",
        "zone4": "132 to 167 bpm",
        "zone5": "168 to 180 bpm",
        "zoneOf": "Zone 3: moderate",
        "method": "Heart rate reserve (Karvonen)"
      },
      "source": "ACSM %HRR classes (Garber 2011) with Karvonen 1957: 60 + 0.3 × 120 = 96, 0.4 → 108, 0.6 → 132, 0.9 → 168; hand calculation in content.mdx"
    },
    {
      "given": {
        "age": 50,
        "formula": "tanaka",
        "hr": 150
      },
      "expect": {
        "max": 173,
        "zone2": "99 to 110 bpm",
        "zone4": "133 to 165 bpm",
        "zoneOf": "Zone 4: vigorous"
      },
      "source": "Tanaka 2001: 208 − 0.7 × 50 = 173; 173 × 0.57 = 98.61, × 0.64 = 110.72, × 0.77 = 133.21, × 0.96 = 166.08; hand calculation in content.mdx"
    }
  ],
  "sources": [
    "Garber CE, Blissmer B, Deschenes MR, et al. Quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in apparently healthy adults: guidance for prescribing exercise. American College of Sports Medicine position stand. Med Sci Sports Exerc. 2011;43(7):1334-1359 (Table 4, relative intensity classes). https://doi.org/10.1249/MSS.0b013e318213fefb",
    "Karvonen MJ, Kentala E, Mustala O. The effects of training on heart rate; a longitudinal study. Ann Med Exp Biol Fenn. 1957;35(3):307-315. https://pubmed.ncbi.nlm.nih.gov/13470504/",
    "Tanaka H, Monahan KD, Seals DR. Age-predicted maximal heart rate revisited. J Am Coll Cardiol. 2001;37(1):153-156. https://doi.org/10.1016/s0735-1097(00)01054-8",
    "Centers for Disease Control and Prevention. Target Heart Rate and Estimated Maximum Heart Rate (220 − age; archived copy). http://web.archive.org/web/20221225180518/https://www.cdc.gov/physicalactivity/basics/measuring/heartrate.htm"
  ],
  "related": [
    "target-heart-rate",
    "max-heart-rate",
    "calories-burned"
  ],
  "changelog": []
}