Recently, two studies have shown that women (of all ages) are indeed a lot less active than their male peers.
Researchers studied activity levels in school children and the over 70s - and in both cases found males tended to be more active.
Researchers at Liverpool John Moores University found girls take part in 6 percent less vigorous playtime activity than boys.
The researchers, who focused on 10 and 11 year-old children in the school playground, found that boys and girls tend to play differently.
"Our study shows that girls and boys play differently. Girls tend to spend time in smaller groups and engage in verbal games, conversation and socializing. Most boys play in larger groups, which lend themselves more to physically active games, such as football," Dr Nicky Ridgers said.
While the study does not show the impact playtime activity has on a child's weight, the team believes it may be a factor.
Data from the National Child Measurement scheme has shown that by the age of 11, 33 per cent of children are overweight or obese.
This data shows no major difference between girls and boys, though other research has shown that adult women are more likely to be clinically obese than men.
"It is a concern that girls' activity levels are lower than boys and, although it is just one piece in a complex picture, this could be contributing to girls being overweight and obese," Dr Ridgers said.
The gender difference was mirrored in a second study, led by the University of Bristol, which looked at activity levels among the over-70s.
In general, levels of physical activity were very low among most people of both sexes aged over 70.
More than 70 percent of the people who took part in the study walked for fewer than 5,000 steps a day.
However, women were more likely to be less active than men.
"Men accomplish higher intensity physical activity than women and this seems to be explained by trips out of the house. However, there is evidence that they also sit down for longer periods in the day. Women do lower intensity activity which probably represents daily tasks around the house," said Ken Fox, Professor of Exercise and Health Sciences at the University of Bristol (UK).
"This would suggest that traditional family roles are still identifiable in this generation. We are now taking a closer look at what may lie behind this gender difference and are attempting to identify the best ways of promoting physical activity to help improve mental well-being and physical fitness among the over 70s," Fox added.
The two studies are being presented at the UK Society for Behavioral Medicine annual conference (incorporating the National Prevention Research Initiative conference) at the University of Exeter (UK).