The rate of depression among college students was up to 90 percent higher in the early months of the coronavirus pandemic, compared with pre-pandemic levels, according to an analysis of how disruptions in students’ daily life affected their mental health. At highest risk for depression were students whose physical activity declined the most in that time period — for instance, being active one to two hours less a day, or dropping from 10,000 to 4,600 steps a day. At lowest risk were those who maintained their activity level. Published in Proceedings of the National Academy of Sciences, the researchers cited “stark increases in depression” in just a few months, from about 32 percent to 61 percent of the 682 students, based on results from standard diagnostic scales. In addition to assessing physical activity, the study also found that stay-at-home orders, campus closures and social distancing led, on average, to students socializing less (to less than 30 minutes a day), sleeping more (by 25 to 30 minutes a night) and doubling their screen time (to more than five hours a day). Other recent research has found similar mental health effects related to physical fitness. Physical activity is known to help people get and stay strong, energetic and healthy. Its mental health benefits may stem from prompting the release of feel-good brain chemicals, known as endorphins, and from simply taking your mind off the negative thoughts that may be feeding anxiety or depression. Doctors, parents and students themselves all report an uptick in depression among young people since the pandemic began, restricting life in many ways.