Think happy people are more likely to exercise? Maybe not.
According to new research, people in a more neutral frame of mind (defined as those who aren't overly happy or too sad), are more likely to exercise compared with people who are in a more positive mood or who are feeling down.
What's more, feeling sad or having other negative emotions strongly influences a person's decision to work out.
During the study, researchers divided 153 college students into three groups. One group watched a segment from the TV show "America's Funniest Home Videos." A second viewed a sad scene from the movie "Marley & Me" in which a family pet dies and a third group watched a clip from a business documentary. Each video was designed to help put students in either a positive, negative or neutral mood, respectively.
After students watched eight to 10 minutes of the happy, sad or neutral video, they completed a fitness questionnaire. The survey asked how often students regularly exercised and how often they intended to be physically active. The survey also included questions designed to discover whether watching the videos made the viewers feel upbeat, sad or neutral.
Results from the fitness survey showed that nearly 72 percent of the students had exercised during the past three days and slightly more than two-thirds worked out at least three times a week. Those are higher rates of activity than typically found in other surveys of college students, according to the researchers, making the students in this study a motivated group. Both students in the upbeat and neutral mood groups also reported high levels of happiness.
After asking students about their intentions to exercise, researchers had expected that happy people would be more likely to say they planned to exercise than those who had a neutral or sad outlook. However, students who watched the upbeat video said they were less likely to plan physical activity than those in the neutral group. People who watched the sad video had the weakest intentions to exercise.
"Our study showed that regardless of emotional state, people generally believe that exercise is a behavior that they should be engaging in," said study author Jennifer Catellier, an assistant professor of communication at John Carroll University in University Heights, Ohio. "However, when they made more emotional decisions, they went against these beliefs, deciding that other activities were more appealing than exercise."
It's possible that watching a feel-good video may have distracted the upbeat people, prompting them to consider other, less active behaviors, Catellier suggested.
On the other hand, "feeling sad seems to depress attitudes about the behavior, meaning exercise doesn't seem as beneficial as it does to happier people," Catellier said. "So, ultimately, these people don't exercise."
Finally, people who are in a neutral emotional state are still generally happy, but haven't been exposed to emotional stimuli that might influence their decisions, Catellier said. "These people are likely making more thoughtful decisions than the people who were made to watch the happy or sad videos," she added.
The study suggests that sometimes emotions — both positive and negative —prevent people from engaging in beneficial health behaviors such as exercise. The study also found that negative emotions played a greater role in sabotaging the intention to exercise than feeling happy played in increasing the likelihood of working out.
To encourage regular physical activity, it's helpful to understand how emotions influence behaviors, said Catellier. If being sad makes people feel lazy, it is important to find ways to work through that, she pointed out.
People shouldn't let either negative or positive feelings about other situations in their life prevent them from engaging in behaviors like exercise that are important and worthwhile, Catellier suggested.
"It might not be easy, but basing decisions on information and knowledge — instead of emotions or feelings — may help you make decisions that are ultimately better for your health," Catelier said.
The study will appear in the March issue of the journal Psychology of Sport and Exercise.
Pass it on: Emotions can sometimes derail exercise plans.
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Cari Nierenberg has been writing about health and wellness topics for online news outlets and print publications for more than two decades. Her work has been published by Live Science, The Washington Post, WebMD, Scientific American, among others. She has a Bachelor of Science degree in nutrition from Cornell University and a Master of Science degree in Nutrition and Communication from Boston University.