London, Apr 8 (IANS): A new study has shown that women, who exercise during pregnancy, are likely to give birth to lighter babies.

The research led by University of Auckland scientists showed that mothers-to-be who underwent fitness training on exercise cycles had lighter babies than women who did no exercise.

"Our findings show that regular aerobic exercise alters the maternal environment in some way that has an impact on nutrient stimulation of fetal growth, resulting in a reduction in offspring birth weight," telegraph.co.uk quoted Dr Paul Hofman, from the University of Auckland in New Zealand, as saying.

''Given that large birth size is associated with an increased risk of obesity, a modest reduction in birth weight may have long-term health benefits for offspring by lowering this risk in later life,'' Hofman added.

In the trials involving 84 first-time mothers, the participants were asked to exercise that consisted of stationary cycling, which involved a maximum of five 40 minute sessions per week.

The findings revealed that the women who exercised had babies that were on average 143 grams lighter than those of women who did not exercise.

The study showed that babies were not shorter in length and there was no evidence that they lacked nutrition.

The findings appear in the Journal of Clinical Endocrinology & Metabolism.