From sitting through lectures to studying at libraries to eating at dining halls, Yalies spend the majority of their time exercising little more than their cerebellums. Despite the popular New Year’s resolutions to lose weight and get fit, students say exercise typically remains a low priority on their Google calendars and to-do lists.

“The average Yalie is lazy when it comes to getting to the gym,” Carolyn Brotherton ’10 said. “At the end of a long day, you’re just so tired, and it’s the last thing you want to do.”

But the Yale student’s inactive lifestyle may have far-reaching ramifications, said Chronic Disease Epidemiology professor Melinda Irwin, whose primary research interests are in the areas of physical activity and cancer prevention.

Staying active, she said, can have both physiological and psychological benefits.

“People who exercise have improvements in their quality of life,” she explained. “They have lower rates of depression, anxiety and stress and better sleep habits.”

A recent Tufts University study found that students who said they exercised at least 3 days a week were more likely to report a better state of physical health and greater happiness than those who did not.

Exercise also optimizes the balance of certain hormones, such as insulin and cholesterol, in the body, Irwin said, meaning that staying active can reduce susceptibility to certain diseases.

“Physiologically, not only does exercise help maintain lean body mass or bone mass, but it also favorably influences hormones that are related to certain diseases such as diabetes and heart disease,” she said.

Longitudinal studies of healthy people have linked greater levels of exercise with a lower risk of developing diseases such as colon and breast cancer, Irwin said. And retrospective studies of patients of colon and breast cancer have also shown that they have, on average, histories of lower physical activity levels than their healthy counterparts when the two groups are controlled for their demographic characteristics, she said.

Exercise may even promote recovery from disease. Irwin said studies have shown that being active following a sickness lowers the risk of its recurrence.

The level of physical activity currently recommended for people between the ages of 18 and 22 is 30 minutes of moderately intense activity, she said, such as brisk walking or bicycling every day, or 30 minutes of vigorous activity such as running, three times a week.

But many Yalies may not be getting this recommended amount, she said.

Brotherton said that Yale students typically fall into two broad categories: athletes who exercise large amounts to stay fit, and those who “don’t do it at all.”

Indeed, Lisa Vienneau ’10, a track and field athlete, said while her exercise routine becomes more flexible during midterm week and finals, for most of the year she and her fellow athletes follow stringent schedules.

Of course, some Yalies are exceptions to these two categories. Many — like Kevin Chow ’08 — do carve out time in their busy schedules for weekly trips to the gym.

Chow, who exercises an average of two times a week, said the regular physical activity is mentally refreshing.

“It provides a good break from work,” he said. “It also helps me concentrate when I get back to it.”

But Irwin said exercising must be sustained in order for students to reap its benefits, which is tough during breaks, when summer jobs and internships displace gym time.

“It’s like a drug, and if you stop taking it, you stop feeling its effects,” she said.

Studies show that high levels of activity maintained throughout one’s life are correlated with the most favorable health outcomes.

But Yalies may still have a chance to get fit, as long as they do not remain sedentary forever. Irwin said some exercise is better than none at all, even late in life.

Studies show that such people are, in fact, at lower risk for certain diseases than those who remain inactive their entire lives, and even at lower risk than those who are active in their earlier years and inactive in their later years.