Motivation to exercise affects behavior

"Many of us set New Year's resolutions to be more physically active, and we expect these resolutions to be stable throughout the year," said David Conroy, professor of kinesiology. "One of the things we see in this study is that from week to week our motivation can change a lot, and these weekly changes in motivation can be destructive to our resolutions."

Conroy and colleagues recruited 33 college students and assessed over a 10-week period both the students' weekly intentions to be physically active and their activity levels. During each of the ten weeks, participants were instructed to log on to a website and to rate their intentions to perform physical activity for the week ahead. To assess physical activity, participants were instructed to wear pedometers each day for the first four weeks.

The team found that for many of the participants, the motivation to exercise fluctuated on a weekly basis, and these fluctuations were linked to their behavior. The results appear in the current issue of the Journal of Sport & Exercise Psychology.

"Our motivation to be physically active changes on a weekly basis because we have so many demands on our time," said Conroy. "Maybe one week we're sick or we have a work deadline -- or, in the case of students, an upcoming exam. But these lapses in motivation really seem to be destructive. Our results suggest that people with consistently strong intentions to exercise have the best chance of actually following through on their intentions, while people with the greatest fluctuations in their motivation have the hardest time using that motivation to regulate their behavior."

According to Amanda Hyde, graduate student in kinesiology, the latter group may still be successful at incorporating physical activity into their lives.

"Maybe the way to get these people to be more physical active isn't necessarily by increasing their motivation" she said, "but rather by changing the way they do things in their lives so exercise automatically fits within their schedule, like walking to work rather than driving or taking the stairs rather than the elevator."

Conroy added that consistency of intentions is not the only thing that matters in predicting whether or not a person will be active. It also matters if it is a weekday or the weekend.

"We saw that people who consistently reported stronger intentions to be active were more active during the week, but then on weekends the pattern flipped for them," said Conroy. "If a person was really motivated during the week, then he or she crashed on the weekend."

Conroy noted that people seem to have different systems that motivate their behavior during the week and on the weekend.

"We speculate that this reflects the fact that college students are in the midst of a transition that significantly increases their autonomy," said Conroy. "They have to manage their time much more effectively during the week because they have so many more demands, such as course schedules, job schedules and extracurricular activities, whereas on the weekends they have more discretionary time that they can choose to spend as they wish. Students may be exhausted from having regulated their behavior and managed their time so carefully during the week that on the weekends they need to recharge their batteries and throw their time management out of the window. If we had done this study with mid-life or older adults, I don't know that we would have seen the exact same pattern."

Regarding New Year's resolutions, Conroy advised that people should focus less on making broad commitments to becoming more active and instead come up with a plan for how they're going to sustain their motivation from one week to the next.

"It is important to pay attention to how we can sustain a high level of motivation and not just let that motivation degrade in response to all the external demands we face," said Conroy

Other authors on the paper include Steriani Elavsky, assistant professor of kinesiology, and Shawna Doerksen, assistant professor of recreation, park and tourism management.

The National Institute of Aging at the National Institutes of Health supported this research.