When we sit for long periods, the body’s metabolism turns off. Muscles cease to move and heart action slows. Next the body’s calorie-burning rate plummets, insulin loses much of its effectiveness and fat levels rise.
Those of us who find ourselves spending many hours each day in front of a computer or TV screen should be thrilled to learn that we can take a giant step to better health and a long life simply by standing up regularly and moving around a bit. As one exercise expert has neatly pronounced, “The greatest health benefit from exercise comes from getting up off the couch.” The rest, he added, is only incremental.
Researchers tell us we lose years off our lives by allowing our bodies to sit around like couch potatoes for long periods. This puts us at risk of becoming obese, or acquiring raised blood pressure, high blood sugar and/or elevated cholesterol, not to mention becoming increasingly susceptible to heart attacks and some cancers.
When we sit for long periods, Mayo Clinic obesity authority Dr. James Levine says, the body’s metabolism turns off. Muscles cease to move and heart action slows. Next the body’s calorie-burning rate plummets, insulin loses much of its effectiveness and fat levels rise. A person can exercise mightily after all this, but it won’t repair all this damage.
How much is enough?
This is only one of the important findings to emerge in the last few years as researchers deepen their investigation into how the body reacts to exercise and the lack thereof, and pursue their search for more effective – and speedier – ways of promoting the body’s good health. The research, which continues to pour forth from labs and medical clinics, gives people a range of choices as to what they want to achieve by exercising, and how much effort they are ready to commit.
As it turns out, the research hasn’t yet determined exactly how much exercise we need to remain healthy or fit (healthy implying a heightened ability to ward off setbacks to our health while fitness means that our heart and lungs are strong and able to deliver oxygen efficiently to our muscles). What is known is that innovative techniques now used can successfully offer these benefits, and with astonishing time savings.
The standard, widely-adopted guidelines regarding exercise levels, offered by the United States health department, recommended 150 minutes of regular workouts per week, such as walking. Alternately, the guidelines propose 75 minutes per week of intense, aerobic effort – as in jogging or other strenuous exercise – to achieve the same benefits.
HIIT it hard
But today’s approaches, emerging out of research on several continents, carves large amounts of time off the old routines, as people in growing numbers take up an aerobic exercise technique called high intensity interval training.
First tried out in an early form over two decades ago, HIIT can produces impressive body improvements in remarkably short order.
In simple terms HIIT combines a short period of intense exercise – this can be near the maximum a person’s body and heart allows – followed by a period when body movement is quickly slowed to a normal or even sub-normal speed. The two-stage procedure is then – normally – repeated a few times. The full exercise protocol will typically be repeated once or more likely twice during the week.
In the brief period of intense exercise, chemical by-products such as lactate, hydrogen ions, phosphate and potassium will accumulate in the blood and begin to circulate in the body, causing muscle pain to develop. The effect will dissipate within an hour, but the interval of slowed-down body movement calms things down much more quickly.
Meanwhile the body will have benefitted from the intense exercise, with the blood’s oxygen content reaching its maximum, a faster heart beat increasing blood flow to muscles in the body and delivering a much-increased amount of oxygen. As the weeks pass, the body will grow stronger and more fit.
There are many ways of assembling the numbers for the intense and slowed down sequences. Some workouts are quite extreme. Some – as outlined in a review of interval training from the Mayo Clinic – quite relaxed and responsive to the body’s changing needs.
Four times three equals fit
One of the most famous of these HIIT protocols came out of Norway, with backup research supplied by Canadian and U.S.teams, The technique was tried out in a set of clinical tests involving two groups of overweight and inactive middle-aged men, exercising three times a week.
One group followed the HIIT interval process with four bursts of intense exercise on an inclined treadmill, each for four minutes and each burst separated by three minutes of lower intensity exercise. The other group produced a single burst of intense exercise for four minutes, nothing more, in its three weekly workouts.
After 10 weeks, the two groups were found to have had statistically similar results in all areas tested. Both groups tested out with maximal uptake of oxygen, lowered blood pressure, reduced levels of blood sugars and improvements in body mass.
The second group made headlines by opening up the prospect that a single, intense workout a few times a week could do the same job as the longer HIIT method.
“Just 12 minutes of intensive exercise per week” can improve your health – a couple of British newspapers reported when the results were announced (though neglecting to say exercisers had to warm up at length and afterward cool down, to stretch exercise time to 19 minutes per session).
It must be noted here that aerobic regimens come with two important warnings. First that people whose bodies aren’t accustomed to strenuous exercise should check with their doctors before starting them. And second, that warm up and cool down exercises are essential so the body isn’t damaged by the excessive effort involved.
A final option is available to anyone not ready to commit to a regular exercise schedule. Remember the U.S. health department’s guidelines for putting the body in motion? That 150 minutes per week doesn’t have to be attained in five daily sessions. You can break the numbers down any way you want: walking to and from the grocery store, to the outer limits of a parking lot, up and down the stairs. Use the opportunities that present themselves, and you’ll be on your way.
And look for the Mayo Clinic report, “Workout with interval training”, and its side reports on your computer, or Cathy Johnson’s “Can you boost your fitness in minutes?”