Can a just short little interval exercise help?


 Top Kinetics and exercise information

Ever wonder just how much exercise you really need to get good results? Many people don’t know.A team of researchers from McMaster University wanted to find out.

        They looked at two groups; one was healthy middle-aged men and women and the other were older people who were diagnosed with cardiovascular disease.Each was tested on the stationary bike for things like peak power output and maximum heart rate. As a whole, participants in both groups were out of shape. Researchers wanted to find out if interval training provided the same fitness and health benefits as the more lengthy and traditional moderate endurance training that so many people do.


People in both groups were then put on a program of cycling intervals that included short burst of strenuous exercise at roughly 90 percent of their maximum heart rate followed by one minute of rest. This exercise-then-rest regimen was repeated 10 times over the course of 20 minutes.The results?Both groups showed significant improvements in their health and fitness.Impressed with the results, scientists performed a separate experiment to see if Type 2 diabetes patients could also experience benefits from such training.The answer is yes.

Just a single session of exercise that used one minute of intense training followed by one minute of rest improved blood sugar regulation especially after meals.

Martin Gibala, professor of kinesiology at McMaster who oversaw the high-intensity studies said, “If you have time for regular 30-minute or longer endurance exercise training, then by all means, keep it up. There’s an impressive body of science showing that such workouts are very effective at improving health and fitness. But if time constraints keep you from lengthier exercise, consult your doctor for clearance, and then consider rapidly pedaling a stationary bicycle or sprinting uphill for one minute, aiming to raise your heart rate to about 90 percent of your maximum. Pedal or jog easily downhill for a minute and repeat nine times, perhaps twice a week. It’s very potent exercise and very quickly, it’s done.”And if leaving the house or the office is difficult, use those stairs!

 A study on mortality rate in men with varying levels of physical activity, as would be expected, found that the group of men with high levels of physical activity had a 32% reduction in mortality rate compared to those in the sedentary group. A study on mortality rate in men with varying levels of physical activity, as would be expected, found that the group of men with high levels of physical activity had a 32% reduction in mortality rate compared to those in the sedentary group.  

A subset of these sedentary men began exercising at or around age 50 – after 10 years, these men had the same mortality rate as the men who had been actively exercising all along.1 

In addition to the many well-known benefits of exercise (prevents chronic diseasereduces cancer riskbeneficial for heart health), there is now accumulating evidence that exercise slows aging at the DNA level.

Telomeres are non-coding regions located on the end of linear chromosomes, and they are shortened with each cell division until the cell no longer divides. For this reason, telomere length is an indicator of cellular aging. Telomere length is maintained in actively dividing cells (such as stem cells and immune cells) by an enzyme called telomerase. There is an inverse association between leisure time exercise energy expenditure and telomere length – meaning that those who exercise regularly have “younger” DNA in their immune cells than those who are sedentary.2-3 A study of middle-aged German track and field athletes found not only longer telomeres in immune cells but also increased activity of the telomerase enzyme and decreased expression of cell-cycle inhibitors – molecules that prevent cell division – in these athletes compared to age-matched untrained individuals.4

Collectively, these studies tell us that exercise not only prevents disease, but promotes longevity, even if we get a late start.



1. Byberg L et al. Total mortality after changes in leisure time physical activity in 50 year old men: 35 year follow-up of population based cohort. BMJ 2009;338:b688

2. Ludlow AT et al. Relationship between Physical Activity Level, Telomere Length,

and Telomerase Activity. Med Sci Sports Exerc. 2008 October ; 40(10): 1764–1771

3. Cherkas LF et al. The association between physical activity in leisure time and leukocyte telomere length. Arch Intern Med. 2008 Jan 28;168(2):154-8.

4. Werner C et al. Physical Exercise Prevents Cellular Senescence in Circulating Leukocytes and in the Vessel Wall. Circulation. 2009 Nov 30. [Epub ahead of print]