The formula to predict maximum VO2 is 15.3 x (MHR/RHR). MHR is the maximum beats per minute, and this value equals 208 - (0.7 x age). RHR is the resting heart rate, or beats per minute, and this value equals the number of heartbeats in 20 seconds multiplied by 3.
The Rockport Fitness Walking test is another way to estimate maximum VO2. The formula is maximum VO2 = 132.853 - (0.0769 x W) - (0.3877 x A) + (6.315 x G) - (3.2649 x T) - (0.1565 x H). "W" refers to the person's weight in pounds, "A" is age in years and "G" is a gender value, which is 0 for females and 1 for males. "T" refers to the time in minutes it takes for a person to walk 1 mile, and "H" is the person's number of heartbeats in 10 seconds after the 1-mile walk.