The majority of Hong Kong's children are not getting enough exercise, the Boys' and Girls' Clubs Association warned on Monday.

The association said it surveyed 801 children aged 6 to 17 between January and April, finding that more than 70 percent failed to do 60 minutes of moderate to vigorous physical activity per day – the minimum amount recommended by the World Health Organisation.

Too little exercise can lead to reduced happiness levels, the association said.

Executive director Billie Lau said it might take some time for children to get back into the habit of exercising following the pandemic.

"There are some facilitators …First of all the facilities, so if we can have more friendly facilities then [children] can do more activities or exercises. The next one is the opportunity, so how can we organise more activities or programmes to facilitate the kids to do more exercise," he said.

"And of course it's time and policy, if we can help the parents to have more time or we can help the kids have more time to do sports I think they would do it."

Over half of the surveyed children said they would like to spend more time exercising but are unable to do so because of busy schedules, a lack of space at home or nobody to play sports with them, Lau said.

He said children could find new activities that are interactive and easy to pick up.

"New types of sport can provide more freshness and they can provide more fun and of course will work more on facilitating communications or interactions between the players," he said.

"So it gives children more than sports."

Lau also urged parents to play sports with their kids, saying such activities tend to make children happier.