The ongoing epidemic is a major perturbation to our way of life. Without a possibility to train and compete, for the vast majority of us, living is a permanent frustration. Last year I wrote about a possible way to (try to) keep in shape, linking to an excellent exercise program offered by the National Health Service of UK. In my article on "competition in the times of the epidemic" I broke one of my self-imposed rules and wrote about myself, detailing my personal exasperation due to the lack of training possibilities and competitions for non-olympic sports.
Here I am going, once more, to stray from athletics and propose you something that can be of use, all the more so if the various (inefficient) measures, meant to control the epidemic, are making you missing exercise and be out of shape.
But let us start from the beginning. A team of the University of La Coruña performed a study on a cohort of 165 patients who were known or suspected of a coronary disease. They put them on a treadmill and had them walk or run while they increased gradually the intensity. This test continued until exhaustion of the subjects. The capacity of the participants was measured in metabolic equivalents of task (MET).
The MET is the measure of the rate at which a person expends energy while performing a given task to the energy expended when sitting quietly. Physiologists have fixed the latter at 3.5 mL of oxygen per kilogram per minute, a quantity roughly equivalent to 1 kilocalorie per hour and per kg of body mass. I have already referred to METs in my article cited above.
The La Coruña team let their subjects rest for 15-20 min after the first exercise and then asked them to climb 60 stairs (roughly four flights of stairs) at a fast pace. They had to walk (but not run) continuously without stopping. The time to climb the 60 stairs was recorded and the results of the MET measurement were plotted on a graphic (presented below) as a function of the time to climb the stairs.
(Had I access at the raw data I would have discarded the rightmost point and fitted the remaining ones. This would have changed the value of the parameters of the parabola, but not the conclusions). What is clear from the distribution of the points in the graph is that the subjects who can sustain more than 10 MET of exercise are able to climb the 60 stairs in circa 45 seconds. In fact I believe that the limit in this case is due to the fact that the subjects were not allowed to run. Had running been allowed the ones who could sustain an intensity of exercise of more than 15 MET would have been able to climb much faster. For the group realising 8-10 MET the mean climbing time was of roughly 60 seconds, while those unable to surpass 8 MET were slower, with a mean time exceeding 80 seconds.
And now comes the interesting part. From previous studies we know that 10 MET during a test are linked with a low mortality rate, less than 10 % in 10 years, whereas the persons who cannot reach 8 MET have a statistical mortality rate of 30 % in 10 years. Measuring the MET is a complicated task requiring the installations of a physiology lab. Having correlated the MET to the climb-time, the La Coruña team is offering everybody a simple tool for the assessment of their cardiovascular condition. Of course, the study was performed on individuals where cardiac problems were suspected. But the research team believe that the correlation between the climb-time and the exercise capacity will be similar in the general population.
So, there you have it. If you wish to test your condition, find a four storey building and climb 60 stairs while measuring your time. If you manage less than 45 seconds you can rest on your laurels you can continue with your current training program. If not, start exercising immediately.
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