Getting married doesn't affect workout habits much, but becoming a parent definitely makes people more sedentary, according to a new study that followed more than 800 people over two years.

While new parents may feel like they are always on the go, their physical activity levels — including planned workouts and activities such as walking around the mall or gardening — actually decline, says Ethan Hull, MEd, an exercise physiologist at the University of Pittsburgh. Hull presented the findings at the American College of Sports Medicine annual meeting in New Orleans.

"There was no significant change in physical activity with marriage, but with parenthood, physical activity definitely went down," Hull says.

Physical Activity Study

Hull and his research team followed 843 men and women, on average 24-years-old at the study's start, for two years. They answered a questionnaire about their physical activity levels at the beginning of the study and two years later. They also reported if they had married or become parents in the interim. During the study, 99 of the 383 men and women who were single at the start got married; 40 of the 460 childless men and women became parents.

While physical activity declined overall among all participants, it took the biggest hit among new parents.

At the start of the study, the median amount of physical activity (half got more, half got less) reported by all participants per week was 6 hours and 20 minutes, or a little less than an hour a day, Hull says.

Men's activity levels declined more than women's as they became parents, Hull also found. That could be because they were more active than women at the start of the two-year study, he says.

"Men who stayed childless lost about 50 minutes a week in activity [from study start to end]," he says. "Men who became parents lost 4.5 hours a week. Women who stayed childless lost about 20 minutes a week. Women who became parents lost an hour and 20 minutes a week."

Overall, men and women who became parents lost three hours and 20 minutes a week in physical activity, while those who remained childless lost 30 minutes per week, he says.

"We knew your life would shift focus with parenthood," says Hull, who decided to study the topic after hearing many of his friends talk about how exhausted and overwhelmed they felt as new parents.

"We had a supposition that physical activity would go up when you get married, because if one individual exercises, probably the other will start doing it with them," Hull says. That evidently isn't the case. "Physical activity went down with marriage, but not significantly.

"For those who married, physical activity went down about an hour a week. Those who stayed single lost about 20 minutes," Hull says.

That difference, he adds, is not enough to be considered statistically significant by scientists.

Parents Are Pressed for Time

New parents often say there seems to be no time to exercise, says Richard Cotton, an exercise physiologist and spokesman for the American Council on Exercise, who is also a wellness coach. He is not surprised by the study's findings.

New parents are often pressed for time. "They need to be home in the evening," he says of new parents. "They can't stop at the gym after work. They have to get the kids ready in the morning."

His advice? "Try to exercise in the midday," Cotton advises. "Your day is somewhat protected. Take an active lunch. You can do a lot in a half hour. Take a half-hour walk, fairly brisk. Or you can do strengthening and stretching exercises for a half hour. That leaves you time to take a shower."

"You can also do exercise or activity in 10-minute sessions," Cotton adds, noting that much research has found three 10-minute sessions are equivalent to one 30-minute workout.

"Take the baby with you," Hull advises parents who are trying to find time to work out. "There are baby wraps and baby backpacks, and jogging strollers have gotten better. Except for swimming, if you are going out to jog, walk or bike, there are ways to take the child with you."

But it won't just happen, he acknowledges. "You are going to have to prepare and be organized about how you are going to fit in that physical activity."

This article was reviewed by Louise Chang, MD