There’s a common perception that the summer months are the ideal time of year to focus on health and fitness. Because the weather is pleasant, if not a little steamy, people think that they can be more active and shed weight a little easier. Yet, academics have found evidence that suggests just the opposite. In fact, it may be harder to lose weight in the summertime.

Debra Sheats, an assistant professor in foods and nutrition at St. Catherine University in Minnesota, told HuffPost that our body temperatures (typically around 98.6 degrees) are closer to  the environment’s during the summer months, so our metabolism slows down by about 10 percent.

That’s not the only reason why the summer weather is impeding our goals, however.

“When it is very hot and humid outdoors, we have a tendency to not go outside as much to walk, bike or jog,” Sheats said. “Instead, making the choice to stay inside with the cool air conditioning may mean more time spent at sedentary activities such as reading or activities involving screen time.”

To make matters worse, if we do go outside to be active and enjoy the warm weather, we need to drink water to stay hydrated. This process can also cause a little weight gain. As researcher John Castellani from the Thermal and Mountain Medicine Division of the U.S. Army’s Research Institute of Environmental Medicine discovered, a person’s body weight may “increase by as much as several pounds in the summer due to increased water in the body,” HuffPost reported.

That’s not to say we should avoid water during the summer. It’s crucial we drink water to avoid dehydration. The added weight from water is just a handicap that we all have to overcome in the summertime.

For other reasons as to why it seems harder to lose weight in the summertime, read HuffPost’s story on it here.