Hilary Duff rides around on a scooter with her son.

The 30-year-old actress has admitted she struggles to keep up with her little boy Luca, six, whom she has with her ex-husband MIKE COMRIE, because he has really ''long legs'' so she's bought the ride-along kids' toy so she can whiz around with him.

Speaking to People.com, she said: ''When I get home for the weekends right now, I make sure to hike right away. Luca and I swim all the time, and he is an avid scooter rider, so I got a scooter, too, which is so embarrassing to be an adult on a scooter, but when I'm with him, it's so much fun.

''Then we jump on the trampoline; we have a trampoline in the backyard. And his favourite game is tag right now, and he's so fast. His legs are so long, so I'm actually running as fast as I can, and I can still beat him, but it's a good workout.''

The blonde beauty thinks she's she's a ''pretty hyper person'' but there are some days when she doesn't feel like working out or going out so she cooks instead.

She explained: ''On days I don't feel like working out or doing anything too active, I love to stay inside and cook. We go to the movies a lot.''

But with summer just around the corner, Hilary is determined to encourage her son to put his electronic devices down and get outside in the fresh air every single day.

She said: ''This is the time in the coming weeks to encourage your kids to get outside and be in the sunshine and get happy.

''It's so important to get your kids to set their devices down and get outside and run and play and do whatever kind of activities you enjoy outside, and doing that together. Twenty minutes outside can elevate your mood and boost your happiness.''