17. Aerobic capacity : VO2 Max


Over the past year my aerobic capacity has increased very noticeably. After 90 minutes walking on a treadmill inclined 18% at a speed of 7.0km/hr my heart rate will be under 120bpm and I can easily hold a conversation. That is a significant improvement on a year ago, and I can feel the improvement in breathing in everyday life. Having reached the maximum incline on the treadmill and the maximum walking speed, I started running again after a gap of nearly 50 years, and that was all made possible by an improvement in my aerobic capacity


Aerobic capacity can be assessed objectively in a lab using a test for VO2 Max which measures the maximum rate at which your body is able to use oxygen meand is asured in ml/kg/min. According to David Musnick ("Conditioning for outdoor exercise", published by The Mountaineers Books, 2012) regular aerobic training improves your VO2 Max which will provide greater endurance during physical activity. About half of the improvement is due to the heart's ability to pump and the other half is from increased efficiency in the muscles' ability to extract oxygen for use in supplying energy.


A formal test for VO2Max is expensive because it involves oxygen masks and professional technicians in a lab but if you just want an approximate estimate that can then be used periodically to check training progress then I suggest the following link which was kindly provided to me by Richard, my mentor at the local gym : http://www.runnersblueprint.com/vo2-max/


This link describes the Cooper Method for estimating VO2 Max using a treadmill and a stopwatch, and was devised for use by the American military. The test is very simple : warm up thoroughly then run as hard as possible on a level treadmill for exactly 12 minutes, record the distance covered, then enter that data in the following equation :


VO2 Max = (Distance in meters – 504.9) /44.73   ml/kg/min


On my first test I ran 2350 metres in 12.00 minutes which gave me a VO2 Max of 41.3 ml/kg/min. As per the table below that means that my VO2 Max just nudges in to the “Excellent” category for my age so I confess to feeling very smug! It is only an estimate of course but the basic test is easily repeated and the distance covered provides a repeatable measure of performance improvement even if the VO2 Max figure is only an estimate.