Now there's no excuse to say you don’t have time to work out: research has found that sprint interval training (SIT), a ten-minute exercise routine that includes one minute of intense exercise, may be as effective as a more traditional 50-minute, moderate-intensity continuous training (MICT) routine. For the study, which was published in PLoS One, researchers recruited 27 men, ages 19 to 35, who were considered sedentary. They divided the men into three groups and assigned each group to engage in SIT or MICT workouts, three times per week, or to a no exercise (control) group. The SIT workout consisted of three, 20-second 100% full-force cycle sprints with two minutes of slow cycling in between each sprint. The MICT workout consisted of 45 minutes of continuous cycling at about 70% of maximum heart rate, which is generally determined by age. Both workouts included a two-minute warm-up and a three-minute cool-down.

At the beginning and end of the study, researchers assessed the participants for several fitness measurements including peak oxygen uptake (the maximum amount of oxygen used during exercise), insulin sensitivity index (indicative of the ability of cells to take up glucose for energy), and skeletal muscle mitochondrial content (indicative of muscle cells’ capacity to make energy). After 12 weeks of training, the SIT and MICT groups showed similar fitness improvements:

• Peak oxygen uptake increased by 19% in both exercise groups.
• Insulin sensitivity index and skeletal muscle mitochondrial content increased similarly in both exercise groups.
• The non-exercising control group experienced no significant changes in markers of fitness.

So, if you’re short on time but want to get fit (a good goal!), you may want to give SIT a try. Just remember that, while short, SIT is the epitome of “No pain, no gain.” The level of intensity needed to complete the SIT workout requires extreme effort and may not be right for everyone. Don’t be afraid to shop around, though: there are other short, high-intensity workouts that could be more your speed.

Source: PLoS One