The answer at a glance
Man, 45, 80 kg, 14:30, 135 bpm
40.1mL/kg/min
Kline's 1987 equation. The worked example is further down.
Typical error in the check group
± 0.355L/min
About 4.4 mL/kg/min at 80 kg. The calculator works it out at your weight.
Adults in the study
343
165 men and 178 women, aged 30 to 69.
Correlation in the check group
0.92
169 adults the equation was not built on.
Key Takeaways
- Enter your 1-mile walk time, your heart rate over the last quarter mile, your age, sex and weight. You get an estimated VO2 max, how far off it could be, your walking pace, and where you sit against a Norwegian reference group.
- The equation comes from a 1987 study of 343 adults aged 30 to 69[1]. On 169 people it was not built on, the correlation with measured VO2 max was 0.92 and the typical error was 0.355 L/min.
- A second, mL/kg/min version of the equation is widely printed. The 1987 abstract says it exists but does not print it[1], so the numbers here come from a thesis and a handout[6][7] and are shown only as a cross-check.
- Accuracy drops outside the people it was built on: under 30[2], on a treadmill[3][12], above 69, or if you take a medicine that lowers your heart rate[8][9]. A slow stroll is not what the test was built for either[7].
What the Rockport Walking Test Is
You walk one mile as fast as you can, note the time and your heart rate near the end, and an equation turns those into a VO2 max estimate.
Kline and colleagues published it in 1987 as an alternative field test[1]. Their equation uses walk time, heart rate, age, sex and body weight. A quicker mile at a lower heart rate points to better aerobic fitness.
It is a submaximal test, so it suits people who would rather not run flat out. If you can run and prefer a distance test, the Cooper 12-Minute Test Calculator and the 1.5 Mile Run Test Calculator use different equations. The VO2 Max Calculator also has a Rockport method next to other ways of estimating VO2 max.
How to Do the Rockport Walking Test
One flat, measured mile, walked briskly, with your heart rate noted over the last quarter mile.
- Pick a flat, measured mile. On a standard 400 m track, 4 laps is 1,600 m, which is 9.3 m short of a mile, so walk a little past the fourth lap.
- Walk as fast as you can without jogging, and time the whole mile. Kline's walkers did it as fast as possible on a track[1]. A University of Wisconsin thesis with 35 adults concluded the test has to be walked at a brisk pace or faster to predict VO2 max accurately[7].
- Record your heart rate over the last quarter mile. A heart rate monitor makes this easy, and it matches the study, which recorded heart rate every quarter mile[1].
- A University of Michigan handout describes a different habit: a 15-second pulse count straight after the walk, multiplied by four[6]. No source checked here compares the two, so pick one and use it every time.
- Enter the minutes and seconds, your heart rate, age, sex and weight, then press Calculate.
Kline's walkers did at least two walks, and the two fastest, within 30 seconds of each other, were used[1]. Repeating your own walk on another day under the same conditions gives you a better picture than a single try.
Before a hard walk
If you have a heart or lung condition, take medicine that affects your heart rate, or have not exercised in a long time, get medical advice first.
Rockport Test Formula and Worked Example
VO2 max in L/min = 6.9652 + 0.0091 × weight (lb) − 0.0257 × age + 0.5955 × sex − 0.2240 × time − 0.0115 × heart rate, then divided by your weight in kilograms.
Kline 1987, L/min (printed in the abstract)
VO2 = 6.9652 + 0.0091×WT − 0.0257×AGE + 0.5955×SEX − 0.2240×T − 0.0115×HR
WT in pounds, SEX is 1 for men and 0 for women, T is minutes, HR is the fourth quarter-mile heart rate.
mL/kg/min version (secondary sources)
VO2 = 132.853 − 0.0769×WT − 0.3877×AGE + 6.315×SEX − 3.2649×T − 0.1565×HR
The 1987 abstract says equations in mL/kg/min were also generated but does not print them. These numbers are from a Wisconsin thesis, which quotes r = 0.88 and SEE 5, and a Michigan handout.
Your main result uses the first line. It gives litres of oxygen per minute, and the calculator divides by your weight in kilograms to get mL/kg/min. Weight therefore counts twice: it adds 0.0091 L/min per pound, and it is the divisor at the end[1].
Litres per minute = 6.9652 + 0.0091 × 176.4 lb − 0.0257 × 45 + 0.5955 × 1 − 0.2240 × 14.50 min − 0.0115 × 135 bpm = 3.209 L/min
3.209 × 1000 ÷ 80.0 kg
The same person on the mL/kg/min version gets 39.7, which is 0.4 lower. The calculator shows both so you can see the gap for your own numbers.
| Time for 1 mile | 110 bpm | 130 bpm | 150 bpm |
|---|---|---|---|
| 12:00 | 50.7 | 47.8 | 45.0 |
| 13:00 | 47.9 | 45.0 | 42.2 |
| 14:00 | 45.1 | 42.2 | 39.4 |
| 15:00 | 42.3 | 39.4 | 36.6 |
| 16:00 | 39.5 | 36.6 | 33.8 |
| Time for 1 mile | 110 bpm | 130 bpm | 150 bpm |
|---|---|---|---|
| 12:00 | 48.6 | 45.1 | 41.5 |
| 13:00 | 45.2 | 41.6 | 38.1 |
| 14:00 | 41.7 | 38.2 | 34.6 |
| 15:00 | 38.3 | 34.7 | 31.2 |
| 16:00 | 34.8 | 31.3 | 27.7 |
How Accurate Is the Rockport Test?
Good for tracking and for ranking, less certain for one person's exact VO2 max.
Kline built the equation on 174 adults and checked it on another 169. In the first group the correlation was 0.93 with a standard error of 0.325 L/min. In the second it was 0.92 with 0.355 L/min[1].
A standard error of 0.355 L/min is about 4.4 mL/kg/min for someone who weighs 80 kg, and more for lighter people. That is why the calculator prints the error at your own weight.
A small study of 24 moderately to highly fit US Air Force men, mean age 33, found no significant difference between predicted and measured VO2 max (measured mean 50.3 mL/kg/min, r = 0.817)[5]. It supports the test for people like them and says little about anyone else.
For the mL/kg/min version, the thesis quotes r = 0.88 and SEE 5[7]. Those figures could not be checked against Kline's paper, so the error range on this page uses the L/min figures instead.
Who the Rockport Test Does Not Suit
The equation is only as good as the people it was built on, and the research points to five places where it slips.
- Under 30. Dolgener and colleagues tried it on college students and it read 16 to 18% too high for men and 22 to 23% too high for women, with correlations of 0.39 to 0.59. They said it should not be used with that group[2]. The abstract does not give their ages.
- Over 69. Kline's walkers were 30 to 69[1]. The Michigan handout mentions a 1993 validation in elderly women[6], but that study could not be found to check, so an accuracy figure for this age is unavailable.
- Treadmills. The evidence is mixed. Widrick and colleagues found the equation worked overall on a treadmill (r = 0.91, total error 5.26 mL/kg/min) but underpredicted men with a high VO2 max[12]. Pober and colleagues, testing 304 adults aged 40 to 79, judged it inappropriate for treadmill walking and built a new equation (r = 0.87, SEE 4.7 mL/kg/min)[3]. On a nonmotorized curved treadmill, 23 adults aged 19 to 44 were underestimated despite correlations of 0.75 to 0.91[4]. If you can, use a track, as Kline's walkers did.
- Slow walking. In the Wisconsin thesis, the brisk walk predicted VO2 max better than a comfortable one, and the author concluded the test must be done at a brisk pace or higher[7]. A relaxed stroll is not what the equation was built for.
- Heart-rate medicine. The equation reads a lower heart rate as better fitness. ACE says beta blockers typically blunt exercise heart rate by 10 to 40 beats per minute[9]. In 28 adults aged 21 to 59, 10 mg of propranolol made a different test, the Ekblom-Bak cycle test, read 11.2% too high[8]. That was not tested on the Rockport walk, so take it as a warning and not a measured error.
What to do with that
If any of these apply, read the estimate as a rough guide. The change between your own walks, on the same track and with the same way of taking your heart rate, tells you more than the exact figure.
What Changes Your Result Most
Walk time and heart rate move the estimate the most, and the table in your result shows it for your numbers.
In the worked example, each extra minute on the mile lowers the estimate by about 2.8 mL/kg/min, and each extra beat per minute lowers it by about 0.14. Those come straight from the coefficients, 0.2240 L/min per minute and 0.0115 L/min per beat[1].
That makes heart rate worth getting right. A reading 10 beats too low would flatter this example by about 1.4 mL/kg/min.
In real life the two inputs are linked, since walking faster is harder work. The equation still treats them as separate, so changing one and holding the other fixed is arithmetic, not a prediction.
The optional target field works the same way. It gives the time the equation needs to reach your target at the heart rate you entered.
Is My Result Good? Rockport Norms
No primary Rockport rating table was found, so the calculator compares you with measured data instead.
Age and sex rating charts for the Rockport test circulate online. No primary source for them could be traced, so this page does not print them.
The calculator compares your estimate with HUNT3, a lab-measured Norwegian group aged 20 to 90[11]. It is a treadmill reference, not a Rockport norm, so allow for error either side. The means and standard deviations by decade are on the VO2 Max Calculator page.
Your finishing heart rate is shown against 208 − 0.7 × age, the average-based estimate of maximum heart rate from Tanaka and colleagues[10]. Individual maximums vary, so treat it as context and not a target.
Other Tests on This Site
If a mile walk does not suit you, one of these may.
What This Calculator Does Not Cover
These were left out because they could not be tied to a source.
Rockport age and sex rating tables
They circulate widely, but no primary source was traced. The HUNT3 comparison is used instead.
Sex-specific equations
Kline's abstract says they were generated but does not print them, and their numbers could not be checked.
A treadmill equation
Pober and colleagues built one, but its coefficients were not read from the paper. Use a track.
Corrections for heart-rate medicine
No source gives a correction for the Rockport walk, so none is applied. A warning is shown instead.
Fitness age and training advice
Turning a Rockport result into a fitness age or a plan needs a source for each step, and none was found.
Frequently Asked Questions
Sources & References
- Estimation of VO2max from a one-mile track walk, gender, age, and body weight. Kline GM, Porcari JP, Hintermeister R, Freedson PS, Ward A, McCarron RF, Ross J, Rippe JM. Medicine & Science in Sports & Exercise 19(3):253-259 (1987)
- Validation of the Rockport Fitness Walking Test in college males and females. Dolgener FA, Hensley LD, Marsh JJ, Fjelstul JK. Research Quarterly for Exercise and Sport 65(2):152-158 (1994)
- Development and validation of a one-mile treadmill walk test to predict peak oxygen uptake in healthy adults ages 40 to 79 years. Pober DM, Freedson PS, Kline GM, McInnis KJ, Rippe JM. Canadian Journal of Applied Physiology 27(6):575-589 (2002)
- Estimated VO2max from the Rockport walk test on a nonmotorized curved treadmill. Seneli RM, Ebersole KT, O'Connor KM, Snyder AC. Journal of Strength and Conditioning Research 27(12):3495-3505 (2013)
- The 1-mile walk test is a valid predictor of VO2max and is a reliable alternative fitness test to the 1.5-mile run in U.S. Air Force males. Weiglein L, Herrick J, Kirk S, Kirk EP. Military Medicine 176(6):669-673 (2011)
- Predicting Aerobic Power (VO2max) Using The 1-Mile Walk Test (lab handout, secondary source, author not stated). University of Michigan exercise physiology course material, dated 12/25/05 (2005)
- Speed dependence of the Rockport fitness walking test (thesis, secondary source). French KK. Master of Science thesis, University of Wisconsin-La Crosse (2015)
- The impact of propranolol on the predictive validity of estimated VO2 max by the Ekblom-Bak submaximal cycle test: a double-blind crossover study. Östh S, Helge T, Ekblom-Bak E. Sport Sciences for Health (2025)
- Ask ACE: How to help clients who have heart-related concerns exercise safely. American Council on Exercise, July 2024 (no author stated) (2024)
- Age-predicted maximal heart rate revisited. Tanaka H, Monahan KD, Seals DR. Journal of the American College of Cardiology 37(1):153-156 (2001)
- Aerobic capacity reference data in 3816 healthy men and women 20-90 years. Loe H, Rognmo Ø, Saltin B, Wisløff U. PLoS ONE 8(5):e64319. A correction to Table 2 was published in November 2013 (2013)
- Treadmill validation of an over-ground walking test to predict peak oxygen consumption. Widrick J, Ward A, Ebbeling C, Clemente E, Rippe JM. European Journal of Applied Physiology and Occupational Physiology 64(4):304-308 (1992)
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Disclaimer: This tool is for informational and personal journaling purposes only. Results are estimates based on published formulas and may vary based on individual factors such as genetics, training history, and measurement technique.