Dr S Chakraborty
As a doctor we have been parroting what has been taught in medical school all these years specially how much exercise a person must do. Now things have been turned on its head by a pioneering experiment done by Dr Timmons, a sports physiologist.
He basically selected two person say A and B with identical physical fitness measured objectively by plethora of tests specially Vo2 max which is the ability to extract maximum amount of oxygen from blood by our muscles per kg of body weight. For a average person like me with fair amount of fitness, its around 40, where as for athletes like Farah & Bolt, it is around 8o. A high Vo2 max is at present one of the top markers of a persons cardiovascular fitness, used both for short period sports like sprints and for endurance sports like marathon, mountaineering, cycling etc.
So Dr Timmons made both the person to do exercise for a period of 6 months but differently. Subject A was made to do conventional exercise that we routinely recommend like brisk walking for 45 minutes, 5 days a week whereas B was made to do intense exercise only for 5 minutes. He was made to run from one corner of a room( 20 foot long) to another at maximum pace. He did this for 30 seconds and took rest for 30 seconds and then repeated again. So of overall 5 minutes of exercise period , he actually did running only for 2.30 minutes. But the running was so intense that he felt as if his heart will come out of his throat.
After 6 months of training, the level of fitness was checked objectively. Subject A had marginal increase in Vo2 max from 42 to 46 where as subject B, whose initial vo2 max was 42, astonishingly went to 72. He also had significant improvements in other parameters like lactate tolerance, exercising blood pressure and the time needed by heart to bring its rate to near normal post exercise.
So when a 5 minutes of exercise specially in our time starved and excused life , can do more benefits than a leisure walk of 45 minutes, we indeed have got to have paradigm shift in the way we do exercise. In fact after this experiment, many national advisories of different countries are thinking about scrapping the concept of recommending 5 days of exercise for 30 to 45 minutes. This remarkable experiment has again opened up the debate of how much is enough. For sure its not more the merrier. It is also called as HIIT which stands for high intensity interval training. Well there is conditions apply for HIIT regimen and that is you must have average level of fitness before attempting it. You just can’t get out of couch and do HIIT straight away.
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