(NaturalNews) A workout technique known as interval training can help you get in shape in a fraction of the weekly time investment required by more conventional workout techniques, according to a study conducted by researchers from Liverpool John Moores University (LJMU), the University of Birmingham and published in the Journal of Physiology.
According to World Health Organization recommendations, all people should engage in between three and five hours of endurance training every single week in order to be fit and healthy and to reduce their risk of chronic diseases and early death. Yet, it can be a major challenge for many city dwellers to make that much time for exercise. Indeed, the majority of U.S. adults do not meet exercise recommendations, and lack of time is considered the main cause.
The study compared two separate forms of workout known as High-Intensity Interval Training (HIT). HIT consists of alternating between a vigorous activity (such as running or cycling) and a less vigorous activity (such as walking) - which activities are used and for how long varies depending upon the needs of the individual. HIT programs are popular because they provide comprehensive fitness workouts in a short period of time. For example, a typical HIT workout might consist of 90 seconds cycling on an exercise bike as fast as possible, followed by 60 seconds of slow cycling, repeated five times for a total of a 15-minute workout.
Fitness in just 90 minutes per weekIn the current study, researchers evaluated several health markers of people who had taken part in HIT or Sprint Interval Training (SIT) workouts.
"SIT involves four to six repeated 30-second 'all out' sprints on special laboratory bikes interspersed with 4.5 minutes of very low intensity cycling," researcher Sam Shepherd said.
"Due to the very high workload of the sprints, this method is more suitable for young and healthy individuals. However, anyone of any age or level of fitness can follow one of the alternative HIT programs."
The researchers found that just three half-hour SIT sessions per week improved insulin sensitivity (a marker of health and fitness) as effectively as five one-hour traditional endurance sessions. SIT was also effective at improving delivery of glucose and insulin to skeletal muscle and burning of fat stored in skeletal muscle.
"Additionally, we found a reduced stiffness of large arteries which is important in reducing the risk of vascular disease." researcher Matthew Cocks said.
The findings suggest that HIT and SIT should be effective at reducing the risk of cardiovascular disease, diabetes, obesity and many other conditions associated with aging.
Shepherd further noted that according to the preliminary results of an ongoing pilot study at the University of Birmingham, people between the ages of 25 and 60 rank HIT (performed on exercise bikes) as more enjoyable than traditional endurance training. The study participants also appear to experience greater improvements in mood from HIT than from endurance training.
"This could imply that HIT is more suitable to achieve sustainable changes in exercise behavior," Shepherd said.