Every parent wants resilient kids. But what’s the ideal age to start getting tough with them? Is older better? There’s no perfect answer, but it might be time to take a cue from our Japanese counterparts, many of whom believe kids are never too young for tough love. Increasingly, Japan’s parents are opting for kindergartens that emphasize strict exercise and academic regimens.

One such school is the physical education-oriented Buddy Sports kindergarten in Setagaya Ward, Tokyo. Here, the kids kick off their day with a 3-kilometer run. The runners range in age from three to six, but their youth is not seen as an excuse to slack off. Teachers push them to keep pace, scolding those who complain.

Also on the daily agenda are other sports aimed at basic muscle and coordination development such as gymnastics, basketball, and tennis. Some days, the older children are taken on a five-hour trek to the seventh station of Mount Fuji.

Is It Too Much, Too Soon?

The answer to that depends on your perspective. According to Takeshi Suzuki, Buddy’s founder and principal, these days many parents are overprotective of their children.

With the school mantra being “try your best,” children must be able to perform headstands, back flips on the bar, and five-box vaulting in order to graduate. In the kindergarten’s 30 years of operation, no child has failed to make the grade.

“This means that all children can do those things if you teach them properly,” says Suzuki.

Many of the preschool’s past pupils have since proved him right: Prominent alumni include marathon runner Yuki Kawauchi and soccer star Yoshinori Muto.

The Buddy Sports kindergarten is only one of several preschools in Japan’s capital with a strict approach to learning that parents seem to like. Izumi Kindergarten in Tokyo’s Adachi Ward is another school with a tough curriculum—and a long waiting list. Here the focus is on language and music. Classes start with three minutes of meditation followed by recitals of Rongo (the Analects of Confucius) and haiku. When it comes to piano practice, the kids are blind-folded to help them focus on hitting the right keys.

Science Is on Their Side

Some parents and educators might criticize the schools’ style as too severe, but some science backs up these methods. One study by the U.K. think-tank DEMOS, found that kids raised by caretakers practicing tough love—defined as a mixture of discipline and warmth—are more likely to become rounded personalities, better able to control their emotions, work through challenges, and concentrate on and complete tasks compared to those brought up by cosseting (or completely authoritarian) moms and pops.

Similar thinking exists in the Spartan race community. “Resilience in today’s kids is very low, often because parents and tech are there to make things as easy as possible for them,” says Jay Jackson, who co-developed the Spartan Edge school curriculum that helps students overcome obstacles through grit and toughness.

“However, when the kids are out on a Spartan course, they find themselves accomplishing things they never knew they could,” he says. “It makes them humble. They’re being kicked in the ass by something that they have to work really hard to overcome. And they do.”

Jackson believes that kids need to know you’re coming down hard on them because you believe in their potential, and he says a lot of the Spartan Edge work is about planting a seed.

“The effects might not be fully apparent right now,” he says, “but they will be later as these students become men and women out in the world.”

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