Exercise improves mental health: what is the maximum limit? Many studies suggest that exercising helps people solve a mental health problem and boost their well-being.

Now a new study extends this fact but adding a caution: over-exercising may cause harmful effects on mental health.

In this study, researchers from Yale University in New Haven, CT, investigated the data of 1.2 million people across America. They wanted to know: How much exercise is too much? How exercise affects an individual’s mental health? Which exercises boost welfare?

The investigators found that cycling, team-oriented sports, and aerobic exercise are beneficial for mental health. They have presented these factors in a paper which is now published in The Lancet Psychiatry.

They recruited participants from across the U.S. and they all had participated in the Behavioral Risk Factor Surveillance System survey carried out in 2011, 2013, and 2015.

For the findings, the researchers used participants’ mental and physical health, as well as their demographic information, and health-related behaviors.

The researchers particularly analyzed different kinds of activities such as doing housework, cycling, performing childcare, running, and going to the gym.

“Previously, people have believed that the more exercise you do, the better your mental health, but our study suggests that this is not the case,” said study author Dr. Adam Chekroud.

“Doing exercise more than 23 times a month, or exercising for longer than 90-minute sessions is associated with worse mental health,” Dr. Adam Chekroud concludes.