{"success":true,"version":"v1","request":{"tool":"get_calculator_schema","calculator_id":"rockport-walk-test"},"result":{"entity_type":"calculator","id":"rockport-walk-test","calculator_id":"rockport-walk-test","canonical_url":"https://tttkmbb.com/fitness/rockport-walk-test","name":"Rockport Walk Test Calculator","title":"Rockport One-Mile Walk Test – VO2max Estimate (Kline et al. 1987) with Fitness Norms","category":"fitness","category_name":"Sports & Fitness","tool_name":"estimate_vo2max_rockport","featured_mcp_tool":false,"description":"Estimates VO2max from the Rockport Fitness Walking Test (walk one mile, 1609 m, as fast as possible and record the time and finishing heart rate) with the Kline et al. (1987) regression on weight, age, sex, time and heart rate; the result is classified with Cooper Institute age- and sex-specific norms and expressed in METs.","use_when":"Someone completed a timed one-mile walk with a finishing heart rate and wants a VO2max estimate and fitness rating without running or laboratory testing.","do_not_use_when":"You have a Cooper 12-minute run distance or resting and maximum heart rates (use vo2-max), the person ran part of the mile or could not walk continuously, or the person is highly trained (the equation is inaccurate above about 60 ml/kg/min); informational, not a medical test.","inputs":[{"name":"sex","label":"Sex","type":"enum","required":true,"values":[{"value":"male","label":"Male","aliases":["m","man","men"]},{"value":"female","label":"Female","aliases":["f","woman","women"]}],"description":"Sex category used to select the formula coefficients.","example":"male"},{"name":"age_years","label":"Age","type":"number","unit":"years","required":true,"min":15,"max":90,"description":"Age in years (the equation was developed on adults aged 30–69).","example":30},{"name":"weight_kg","label":"Weight","type":"number","unit":"kg","required":true,"max":300,"exclusive_min":0,"description":"Body weight in kilograms (converted to pounds for the equation).","example":72.57},{"name":"walk_time_minutes","label":"One-mile walk time","type":"number","unit":"min","required":true,"min":5,"max":40,"description":"Time to walk exactly one mile (1609 m) on a flat course, in decimal minutes (15 min 30 s = 15.5).","example":15},{"name":"heart_rate_bpm","label":"Finishing heart rate","type":"number","unit":"bpm","required":true,"min":40,"max":220,"description":"Heart rate immediately at the end of the walk (15-second count × 4, or a monitor).","example":140}],"outputs":[{"name":"vo2max_ml_kg_min","label":"VO2max (estimate)","type":"number","unit":"ml/kg/min","decimals":2,"description":"Kline et al. (1987) Rockport estimate of maximal oxygen uptake."},{"name":"fitness_category","label":"Fitness category","type":"string","decimals":4,"description":"Cooper Institute rating for the person's sex and age group: very poor, poor, fair, good, excellent or superior."},{"name":"norms_text","label":"Norm table row","type":"string","decimals":4,"description":"The age-group thresholds the rating was read from."},{"name":"mets","label":"METs","type":"number","unit":"MET","decimals":2,"description":"vo2max / 3.5 (multiples of resting oxygen uptake)."},{"name":"weight_lb_used","label":"Weight used","type":"number","unit":"lb","decimals":1,"description":"weight_kg / 0.45359237, as entered into the equation."}],"input_schema":{"type":"object","properties":{"sex":{"description":"Sex category used to select the formula coefficients.","type":"string","enum":["male","female"],"examples":["male"]},"age_years":{"description":"Age in years (the equation was developed on adults aged 30–69). Unit: years.","type":"number","minimum":15,"maximum":90,"examples":[30],"x-unit":"years"},"weight_kg":{"description":"Body weight in kilograms (converted to pounds for the equation). Unit: kg.","type":"number","maximum":300,"exclusiveMinimum":0,"examples":[72.57],"x-unit":"kg"},"walk_time_minutes":{"description":"Time to walk exactly one mile (1609 m) on a flat course, in decimal minutes (15 min 30 s = 15.5). Unit: min.","type":"number","minimum":5,"maximum":40,"examples":[15],"x-unit":"min"},"heart_rate_bpm":{"description":"Heart rate immediately at the end of the walk (15-second count × 4, or a monitor). Unit: bpm.","type":"number","minimum":40,"maximum":220,"examples":[140],"x-unit":"bpm"}},"additionalProperties":false,"required":["sex","age_years","weight_kg","walk_time_minutes","heart_rate_bpm"]},"output_schema":{"type":"object","properties":{"vo2max_ml_kg_min":{"description":"Kline et al. (1987) Rockport estimate of maximal oxygen uptake. Unit: ml/kg/min.","type":"number","x-unit":"ml/kg/min"},"fitness_category":{"description":"Cooper Institute rating for the person's sex and age group: very poor, poor, fair, good, excellent or superior.","type":"string"},"norms_text":{"description":"The age-group thresholds the rating was read from.","type":"string"},"mets":{"description":"vo2max / 3.5 (multiples of resting oxygen uptake). Unit: MET.","type":"number","x-unit":"MET"},"weight_lb_used":{"description":"weight_kg / 0.45359237, as entered into the equation. Unit: lb.","type":"number","x-unit":"lb"}}},"formula":"vo2max_ml_kg_min = 132.853 − 0.0769 × weight_lb − 0.3877 × age_years + 6.315 × (male = 1, female = 0) − 3.2649 × walk_time_minutes − 0.1565 × heart_rate_bpm; weight_lb = weight_kg / 0.45359237; mets = vo2max / 3.5","method":"Kline et al. (1987) derived the equation from adults aged 30–69 against treadmill-measured VO2max (r ≈ 0.88, standard error ≈ 5 ml/kg/min); walkers must reach a steady brisk pace and the finishing heart rate must be taken immediately. Norms: Cooper Institute VO2max classification by sex and age group (13–19, 20–29, 30–39, 40–49, 50–59, 60+). Informational, not a medical test.","sources":[{"name":"Kline GM et al. (1987) Estimation of VO2max from a one-mile track walk, gender, age, and body weight, Med Sci Sports Exerc 19:253-259","url":"https://pubmed.ncbi.nlm.nih.gov/3600239/","type":"peer_reviewed","retrieved_at":"2026-09-24"},{"name":"The Cooper Institute – Physical Fitness Specialist Manual: VO2max norms by age and sex (Cooper Institute for Aerobics Research, Dallas)","url":"https://www.cooperinstitute.org/","type":"reference","retrieved_at":"2026-09-24"},{"name":"Wikipedia – VO2 max","url":"https://en.wikipedia.org/wiki/VO2_max","type":"reference","retrieved_at":"2026-09-24"}],"freshness":{"type":"static","max_age_seconds":null,"note":"Deterministic formula with fixed constants; results never go stale. Inputs supplied by the caller determine the output."},"examples":[{"name":"Male, 30 y, 72.57 kg (160 lb), 15:00, 140 bpm","inputs":{"sex":"male","age_years":30,"weight_kg":72.57,"walk_time_minutes":15,"heart_rate_bpm":140},"expected":{"weight_lb_used":160,"vo2max_ml_kg_min":44.35,"mets":12.67,"fitness_category":"Good"},"url":"https://tttkmbb.com/api/v1/calculate/rockport-walk-test?sex=male&age_years=30&weight_kg=72.57&walk_time_minutes=15&heart_rate_bpm=140"},{"name":"Female, 45 y, 65 kg, 17:30, 130 bpm","inputs":{"sex":"female","age_years":45,"weight_kg":65,"walk_time_minutes":17.5,"heart_rate_bpm":130},"expected":{"weight_lb_used":143.3,"vo2max_ml_kg_min":26.91,"mets":7.69,"fitness_category":"Fair"},"url":"https://tttkmbb.com/api/v1/calculate/rockport-walk-test?sex=female&age_years=45&weight_kg=65&walk_time_minutes=17.5&heart_rate_bpm=130"}],"faq":[{"q":"How do I enter a time like 14 min 45 s?","a":"As decimal minutes: 14 + 45/60 = 14.75."},{"q":"Why does a higher heart rate lower the estimate?","a":"For the same walking speed, a higher heart rate means the effort was closer to maximum, implying a lower aerobic capacity; a fit person walks the mile fast with a low heart rate."},{"q":"Is the test suitable for young athletes?","a":"It was validated on 30–69-year-olds and underestimates fit people who cannot raise their heart rate much by walking; use a running test (vo2-max) for them."}],"tags":["rockport walk test","one mile walk test","vo2max walking test","kline equation","aerobic fitness rating","vo2max norms"],"related":[{"calculator_id":"vo2-max","reason":"Cooper 12-minute run and heart-rate ratio estimates."},{"calculator_id":"heart-rate-zones","reason":"Training zones from maximum and resting heart rate."},{"calculator_id":"calories-by-heart-rate","reason":"Use the VO2max estimate in the heart-rate calorie equation."}],"links":{"html":"https://tttkmbb.com/fitness/rockport-walk-test","markdown":"https://tttkmbb.com/fitness/rockport-walk-test.md","json":"https://tttkmbb.com/fitness/rockport-walk-test.json","api":"https://tttkmbb.com/api/v1/calculate/rockport-walk-test","schema":"https://tttkmbb.com/api/v1/calculators/rockport-walk-test","openapi":"https://tttkmbb.com/openapi.json","mcp":"https://tttkmbb.com/mcp"},"version":"v1","updated_at":"2026-09-24"},"timestamp":"2026-09-24T03:50:53Z","next_actions":[{"tool":"run_calculator","calculator_id":"rockport-walk-test","reason":"Run Rockport Walk Test Calculator with the inputs above."}],"links":{"markdown":"https://tttkmbb.com/fitness/rockport-walk-test.md"}}