Researchers Anca Gaston and Harry Prapavessis at the University of Western-Ontario closely examined whether or not a 4-week intervention of exercise could boost both physical and psychological well being in 56 previously inactive pregnant women. Study participants were about 22.5 weeks pregnant on average and they exercised for 30 minutes approximately 4 times each week.

What the findings revealed were a significant improvement in the moods of all the women, in addition to reduction of fatigue. The exercise the participants did was assessed with accelerometers while the women worked out at a moderate to vigorous pace.

Previous research has found that prenatal exercise can help manage musculoskeletal issues, improve sleep, prevent excessive weight gain and shorten labor. A separate study published earlier in the British Journal of Sports Medicine found that moderate intensity exercises about 3 times per week during the second and third trimester reduces the risk of newborns being overweight by 50 percent.

Even with all of this information, around 60 to 75 percent of all women remain inactive during pregnancy.

Researchers also say that while postpartum mood disorders like postpartum depression are widely recognized, the rate of depression, anxiety and fatigue during pregnancy are actually higher and can result in complications with the pregnancy.

Some of the complications resulting from depression during pregnancy include insufficient weight gain, increased substance use, premature birth, small birth weight and reduced intention to breastfeed.

The research authors highlighted that children of mothers who are depressed or anxious during pregnancy have higher cortisol levels at birth and adolescence, impaired cognition skills and greater risk of developmental and mental disorders.

The U.S. based Mayo Clinic recommends at least 30 minutes of moderate exercise most days of the week, with walking being the most recommended for those not use to exercising daily. They also recommend swimming, low impact aerobics and cycling on a stationary bike as other good choices for moderate intensity exercise.

Additionally, fatigue during pregnancy has been associated with an increased risk of caesarean delivery.

The results of the study were announced on August 2 and appear online in the journal Psychology & Health.