By James Limbach
ConsumerAffairs.com
March 16, 2010
The old excuse, "I don't have enough time to exercise" doesn't work any more.
New research published in The Journal of Physiology adds to the growing evidence for the benefits of short term high-intensity interval training (HIT) as a time-efficient but safe alternative to traditional types of moderate long-term exercise.
In other words, it is possible to get more by doing less!
"We have shown that interval training does not have to be 'all out' in order to be effective," says Professor Martin Gibala of Canada's McMaster University. "Doing ten one-minute sprints on a standard stationary bike with about one minute of rest in between, three times a week, works as well in improving muscle as many hours of conventional long-term biking less strenuously."
HIT means doing a number of short bursts of intense exercise with short recovery breaks in between. The study's authors have already shown with young healthy college students that this produces the same physical benefits as conventional long duration endurance training despite taking much less time (and amazingly, actually doing less exercise!)
However, their previous work used a relatively extreme set-up that involved "all out" pedaling on a specialized laboratory bicycle. The new study used a standard stationary bicycle and a workload that was still above most people's comfort zone -- about 95 percent of maximal heart rate -- but only about half of what can be achieved when people sprint at an all-out pace.
This less extreme HIT method may work well for people (the older, less fit, and slightly overweight among us) whose doctors might have worries about them exercising "all-out".
Exercising on your own will also help you avoid the kinds of complaints ConsumerAffairs.com receives regularly about gyms and equipment people use for their workouts.
As an example, Martin of Des Plaines, IL, writes that he signed up for a gym membership with Bally Total Fitness "under very heavy pressure from the salesmen." According Martin, Bally's policy indicates that you have three business days to cancel your membership and receive a full refund. "The following day I canceled my membership," he says, "and Bally Total Fitness never refunded a penny of my money, or ever got in touch with me."
Then there's the case of Anthony of Folcroft, PA, who bought a NordicTrack Adjustable Toning Tube. "While using it, the plastic handle snapped (broke in half) and plastic pieces hit me in the mouth at a high rate of speed due to the tension in the rubber tube." Anthony sustained a swollen lip and a small cut below his lip, and says "I was lucky it did not hit me in the eye."
It's been generally accepted for years that repeated moderate long-term exercise tunes up fuel and oxygen delivery to muscles and aids the removal of waste products. Exercise also improves the way muscles use the oxygen to burn the fuel in mitochondria, the microscopic power station of cells.
Running or cycling for hours a week widens the network of vessels supplying muscle cells and also boosts the numbers of mitochondria in them so that a person can carry out activities of daily living more effectively and without strain, and crucially with less risk of a heart attack, stroke or diabetes.
But the traditional approach to exercise is time consuming. Gibala and his team have shown that the same results can be obtained in far less time with brief spurts of higher-intensity exercise.
To achieve the study's equivalent results by endurance training you'd need to complete over ten hours of continuous moderate bicycling exercise over a two-week period.
The "secret" to why HIT is so effective is unclear. However, the study also provides insight into the molecular signals that regulate muscle adaptation to interval training. It appears that HIT stimulates many of the same cellular pathways that are responsible for the beneficial effects we associate with endurance training.
The upside of doing more exercise is well-known, but a big question for most people thinking of getting fit is: "How much time out of my busy life do I need to spend to get the perks?"
Gibala says "no time to exercise" is not an excuse now that HIT can be tailored for the average adult. "While still a demanding form of training," he adds, "the exercise protocol we used should be possible to do by the general public and you don't need more than an average exercise bike."
The McMaster team's future research will examine whether HIT can bring health benefits to people who are overweight or who have metabolic diseases like diabetes.
