Think for a moment about your school gym classes.

Did you just grin with fond reminiscence or reflexively shudder?

A revealing new study suggests that these disparate responses to memories of physical education classes are both common and consequential.

How we felt during gym classes years or decades ago may shape how we feel about exercise today and whether we choose to be physically active, the study finds. The result may have implications for our understanding of exercise motivation and also for how we should introduce our children to sports and movement.

About two-thirds of adults in the Western world rarely if ever exercise, health statistics tell us.

There are many reasons so many of us are sedentary, but most behavioral scientists agree that our attitudes about exercise play a defining role. If we expect exercise to be fun and enjoyable, we often will exercise. If not, we won’t.