Japan is home to a unique form of bicycle racing where riders must survive this intense 11-month bootcamp if they want to go pro

There are just four sports that patrons in Japan can bet on legally. A form of bicycle racing known as keirin is one of them.

Keirin cyclists compete in two-kilometer track races; they start by following a pacer, then sprint to the finish line.

The sport started in 1948 and was created with gambling in mind. For a while its popularity grew, but it faced a decline in the 1990s and never fully recovered.

Even so, many still seek to join the professional ranks. But becoming a registered keirin racer isn’t easy.

There is a special school that riders must attend; it has an acceptance rate of 10%. The training is intense, lasting six days a week for 15 hours a day for almost a year.

These photos, taken by Chris McGrath for Getty Images, take you inside the Keirin School in Japan and its intense athletic regimen.

Morning wake up is at 6:30. Students prepare their bikes before training. They have 15 minutes to get ready before roll call, and then get loose and warm up ahead of training.

After roll call there's exercising, drills, and cleaning responsibilities. Breakfast is a big deal: Students consume 1,300 calories (double the norm) to prepare for hard physical work throughout the day.

Female keirin students run a set of steps during their morning jog. Becky James, who rode on the keirin circuit for a while, told the Daily Mail that 'the girls all have really short haircuts and they have to wear the same uniforms. It's crazy and very old school. It's the same for the boys too. They were walking around in hats and shorts, and T-shirts had to be tucked in. And if they saw us they had to bow!'

Source: The Daily Mail

Mt. Fuji is seen in the background as students run up a hill during a morning jog. To have the privilege to race, Japanese riders have to be in the program for 11 months. The system is reminiscent of a military setup, and no mobile phones are permitted during training.

The most notorious type of keirin school training is Hill Training. The average person would struggle to move even an inch on this task, where the riders have to cycle up gradients of 14 degrees.

Group racing skills are honed through training. In this session, bicycles are towed so the riders can experience unusual and extreme speeds (which helps their pedal power improve).

It's an intense process throughout the day. Here, a couple of students are taking a breather following a two-hour training session. They won't wrap up the day until 5:30.

While most of their day consists of training, there's time in the classroom. Training theory and race rules are among the subjects covered.

Stationary bikes are used to help improve balance, among the riders, and provides a contrast to outdoor training.

The roller machines aren't quite as simple as they look. A regular person would most likely find them extremely difficult to ride.

In a typical keirin race, nine riders will begin side-by-side in a line, not too far behind each other or a pacer. The race is about two kilometers, and in the final 600 meters the race really gets going when the pacer leaves the track, and what was before a composed line turns into chaos. Fighting for position, it's not unusual for collisions and crashes to occur.

State-of-the-art performance-measurement devices are installed on school grounds. There are only a few of these machines in all of Japan.

Looking at the statistical measurements, the students can analyse and measure their pedalling efficiency. It provides them with actual data where they can objectively examine their results.

It's been a long day. Keirin students walk back to the bike garage in the rain. They will finally be able to bathe and relax.

Back in their dorm rooms, keirin students study. They consume 4,500 calories for dinner to refuel after the extensive day. It helps them prep for the next day. Lights out at 10.

The intense process is worth it. Once students finish the 11-month bootcamp, they earn, on average, $100,000 a year.

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