A Harvard professor says most of us squander 5-minute opportunities to be happier every day

• Don't waste small pockets of free time by mindlessly checking email.
• Instead, consider chatting with a coworker, which might make you happier than you expect.
• That's according to a Harvard Business School professor, who writes that we overestimate how long it will take to enjoy an experience.

Harvard Business Review's recent cover story makes the case for prioritizing time over money, and making daily decisions accordingly. Unfortunately, writes Harvard Business School professor Ashley Whillans, most of us do just the opposite.

One of the most intriguing points in the article is this: "We overestimate the amount of time needed to enjoy an experience." The result, according to Whillans? "We end up wasting small pockets of free time that we could use more effectively. Five minutes spent socializing with a colleague or 20 minutes on an elliptical machine often have more powerful mood benefits than we expect."

Whillans doesn't specify the ways we waste those small pockets of free time, but I immediately thought about checking email or browsing social media in the five or 10 minutes between meetings. That's not enough time to do anything enjoyable, the thinking goes, so we fill it up mindlessly.

One broad lesson here is the importance of approaching free time with intentionality. As time-management expert Laura Vanderkam writes in her book "Off the Clock," "Few people would show up at work at 8 a.m. with no idea about what they'd do until 1 p.m., and yet people will come home at 6 p.m. having given no thought to what they'll do until 11 p.m."

Read more: Here's how to finally stop wasting your precious free time

Like Whillans, Vanderkam specifically recommends socializing with friends and family, noting that those who make time for the important people in their lives are more likely to say they generally have time for the things they want to do. (Vanderkam suspects that socializing causes the feeling of freedom, and not the other way around.) "People expand time," she writes.

Another broad lesson is that we're notoriously poor predictors of how any experience - like working out or chatting with a coworker - will make us feel. Indeed, a 2014 study published in the Journal of Experimental Psychology: General found that people are happier when they talk to a fellow passenger on their commute - even though they think they'd be happier if they kept to themselves.

Bottom line: Time (even five minutes of it) is a precious commodity. Use it wisely.