My 5-year-old daughter looks at me and asks in an unusually quiet voice: “Mummy, am I going to do that?”

We are standing in a basement gym in Daikanyama, rap music blaring, as adults with cartoon-perfect muscles crouch to the ground before springing to their feet and, with a sharp intake of breath, wobble poles of heavy weights above their heads.

“Um, no, I don’t think so,” I reply — although to be honest, I have no idea what exactly my daughters will be doing. We’re waiting for a CrossFit Kids class to begin and — full disclosure — it’s not only my children who are apparently out of their comfort zone, as it’s not often that I find myself in the confines of a gym.

Before signing up to a trial kids class, I have only vague notions that CrossFit is something that makes celebrities such as Madonna extremely fit, strong and bendy, triggering my curiosity as to what this kind of class might entail when tailored for children.

At the CrossFit Daikanyama gym, my guinea pig daughters, aged 5 and 7, are still staring wide-eyed at the muscle-rippling grown ups lifting weights into the air like Popeye (it’s the tail end of an Olympic Lifting class). No doubt, they are wondering where on earth their mother has taken them this time.

Fortunately, they relax slightly when their Lycra-clad teacher Sayaka Takubo, who is as friendly as she is super strong in physique, steps forward to warmly greet them both.

Soon, the adults pack up and head to the on-site bar to order protein smoothies, making way for around half a dozen children (aged between 5 and 11) who take center stage in the gym space — and the class commences.

It starts with each of them, in two teams, running on their hands and feet, forward and backwards, around markers on the floor, amid shouts of “Three, two ,one! Touch! Touch! Touch!” in an atmosphere that brings to mind a fun but extreme school sport’s day race.

Little heavyweights: One of the CrossFit activities for kids involves working out with small kettlebells. | DANIELLE DEMETRIOU
Little heavyweights: One of the CrossFit activities for kids involves working out with small kettlebells. | DANIELLE DEMETRIOU

As I watch my startled daughters attempt to keep up, I chat to a regular CrossFit member (he visits five days a week before work) whose daughter is taking part and I learn a bit more about what it involves. It is, it turns out, an original fitness regime from California that fuses a cornucopia of different high-intensity exercises — pull ups, weightlifting, running, squats, gymnastics, among others — with a strong community focus. This is a more lightweight version adapted for children.

At this point, the girls move to another part of the gym for the next part of the class: weights (yes, really). Here, they are each given a kettlebell weight, depending on their size and experience — my daughters get 4-kilogram weights) — plus a hula hoop, inside which they stand before Sayaka enthusiastically instructs them all to squat up and down and up and down …

Loud music still blaring, my daughters are clearly so stunned they do as they’re told (Takubo is friendly but firm), albeit bending their knees a lot less deeply than the others, before they march around their hula hoops, lifting up the weights.

While some of the older students enthusiastically leap around in an Amazonian manner with weights in each hand, my enduring visual memory of the class is my 5-year-old, clutching a weight with two hands like a little handbag as she delicately stepped around her hoop — I should add, though, it’s a better effort than anything I could muster.

The one-hour class continues to build up in terms of strength and energy levels, culminating in a session involving leaping over bars onto a mattress on the floor, with some kids flying over with gloriously wild abandon, even throwing in the odd fancy forward roll. Others, however, approach it more tentatively, in particular my girls, who initially walk up cautiously, peer at the bar and simply step over it and onto the mattress.

By the end of the class, though, I see that even my daughters are managing to jump, efforts that lead to hot, happy and exhilarated smiles. After we thank Takubo at the end of the class and make our way back outside into the real world, my 5-year-old, clearly harboring Olympic lifting ambitions, turns and innocently asks: “Can we lift the big sticks above our heads next time mummy?”

CrossFit Kids classes take place every Thursday (4:30 p.m.) and Saturday (3 p.m.) at CrossFit Daikanyama; children from age 5 are welcome. Classes cost ¥3,100 a person and are bilingual. For more information, visit www.crossfitdaikanyama.com.

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