A boy touches a robot as it performs Taiji, a traditional form of Chinese martial arts, at the World Robot Conference (WRC) in Beijing, China August 17, 2018. REUTERS/Jason Lee

A martial arts instructor from Dewei Security does Taiji, a traditional form of Chinese martial arts, after a daily training session at a training camp, on the outskirts of Beijing, China March 2, 2017. Picture taken March 2, 2017. To match Analysis CHINA-SILKROAD/SECURITY REUTERS/Jason Lee

Local resident plays Taiji, a traditional form of Chinese martial arts, at Tiantan Park, in central Beijing, China April 16, 2017. REUTERS/Jason Lee

A local resident practices Taiji, a traditional form of Chinese martial arts, outside the National Grand Theatre on a sunny day in central Beijing, China, March 1, 2017. REUTERS/Jason Lee

A resident practices Taiji, a traditional form of Chinese martial arts, near apartment blocks in central Beijing, China February 17, 2017. REUTERS/Jason Lee

A mother pushes a pram past an elderly woman practicing Taiji, a traditional form of Chinese martial arts, at a residential community in Beijing, China, October 30, 2015. The easing of family planning restrictions in China to allow all couples to have two children will benefit around 100 million families, a professor told the official China Daily on Friday. REUTERS/Jason Lee

A 56-year-old man, surnamed Chen, who has yet to reach retirement age, plays with his 2-year-year granddaughter next to an elderly woman practicising Taiji, a traditional form of Chinese martial arts, at a residential community in Beijing, China, October 30, 2015. The easing of family planning restrictions in China to allow all couples to have two children will benefit around 100 million families, a professor told the official China Daily on Friday. REUTERS/Jason Lee

A boy plays in front of an elderly woman practicing Taiji, a traditional form of Chinese martial arts, at a residential community in Beijing, China, October 30, 2015. The easing of family planning restrictions in China to allow all couples to have two children will benefit around 100 million families, a professor told the official China Daily on Friday. REUTERS/Jason Lee

Indian Prime Minister Narendra Modi (C, R) and Chinese Premier Li Keqiang (center, L) pose for pictures with child performers of the Taiji and Yoga event, at the Temple of Heaven park in Beijing, China on May 15, 2015. REUTERS/Kenzaburo Fukuhara/Kyodo News/Pool

Indian Prime Minister Narendra Modi and Chinese Premier Li Keqiang (3rd R) attend the Taiji and Yoga event at the Temple of Heaven park in Beijing, China on May 15, 2015. REUTERS/Kenzaburo Fukuhara/Kyodo News/Pool

Indian Prime Minister Narendra Modi (back L) and Chinese Premier Li Keqiang (back R) observe the Taiji and Yoga event at Temple of Heaven park in Beijing, China on May 15, 2015. REUTERS/Kenzaburo Fukuhara/Kyodo News/Pool

Indian Prime Minister Narendra Modi (L) and Chinese Premier Li Keqiang talk during the Taiji and Yoga event at the Temple of Heaven park in Beijing, China on May 15, 2015. REUTERS/Kenzaburo Fukuhara/Kyodo News/Pool

Indian Prime Minister Narendra Modi and Chinese Premier Li Keqiang (both, C) attend the Taiji and Yoga event at the Temple of Heaven park in Beijing, China on May 15, 2015. REUTERS/Kenzaburo Fukuhara/Kyodo News/Pool TPX IMAGES OF THE DAY

Indian Prime Minister Narendra Modi takes a selfie using a cell phone with perfomers of the Taiji and Yoga event at the Temple of Heaven park in Beijing, China on May 15, 2015. REUTERS/Kenzaburo Fukuhara/Kyodo News/Pool TPX IMAGES OF THE DAY

A demonstrator participates in a "World Love for Dolphins Day" rally outside the Japanese consulate in New York February 13, 2015. According to the Sea Shepherd Conservation Society the second annual "World Love for Dolphins Day" rallies are set to draw international attention to the annual drive hunt in Taiji, Japan, and will take place outside Japanese embassies and consulates across the U.S. and overseas.
REUTERS/Shannon Stapleton (UNITED STATES - Tags: ANIMALS SOCIETY CIVIL UNREST)

Demonstrators participate in a "World Love for Dolphins Day" rally outside the Japanese consulate in New York February 13, 2015. According to the Sea Shepherd Conservation Society the second annual "World Love for Dolphins Day" rallies are set to draw international attention to the annual drive hunt in Taiji, Japan, and will take place outside Japanese embassies and consulates across the U.S. and overseas.
REUTERS/Shannon Stapleton (UNITED STATES - Tags: ANIMALS SOCIETY CIVIL UNREST)

People practise Tai Chi at the the seafront boulevard Malecon in Havana, October 28, 2014. REUTERS/Alexandre Meneghini (CUBA - Tags: SOCIETY)

Animal rights activists protest against dolphin hunting in Taiji, Japan, outside the Japanese consulate in Sao Paulo September 1, 2014. The banner (L) reads, "Assassins" (top) and "Japan". REUTERS/Nacho Doce (BRAZIL - Tags: CIVIL UNREST ANIMALS SOCIETY POLITICS)

A woman practices Tai Chi, a Chinese martial art, during a lunch break at a financial district in Beijing, May 21, 2014.
REUTERS/Kim Kyung-Hoon (CHINA - Tags: SOCIETY)

Former Manchester United player Rio Ferdinand (L) and Manchester City's Sergio Aguero practise Taiji during a promotional event where they compete for the most popular "selfie" in Singapore May 15, 2014. REUTERS/Edgar Su (SINGAPORE - Tags: ENTERTAINMENT SPORT SOCCER)

Former Manchester United player Rio Ferdinand (red) and Manchester City's Sergio Aguero practise Taiji during a promotional event where they compete for the most popular "selfie" in Singapore May 15, 2014. REUTERS/Edgar Su (SINGAPORE - Tags: ENTERTAINMENT SPORT SOCCER)

Former Manchester United player Rio Ferdinand (C) and Manchester City's Sergio Aguero practise Taiji during a promotional event where they compete for the most popular "selfie" in Singapore May 15, 2014. REUTERS/Edgar Su (SINGAPORE - Tags: ENTERTAINMENT SPORT SOCCER)

A man practices Tai Chi in a park at Pudong financial district in Shanghai April 2, 2014. REUTERS/Carlos Barria (CHINA - Tags: SOCIETY)

Dolphins are seen at a cove in Taiji, western Japan, January 21, 2014. Japanese fishermen drove a large group of dolphins into the shallows and killed at least 30 on Tuesday, hiding themselves behind a tarpaulin, as the annual dolphin hunt that sparked protest in the West entered its final stages. Every year the fishermen of Taiji, in western Wakayama prefecture, drive hundreds of dolphins into a cove, select some for sale to marine parks, release some and kill the rest for meat. REUTERS/Adrian Mylne (JAPAN - Tags: ANIMALS ENVIRONMENT POLITICS)

Dolphins are seen at a cove in Taiji, western Japan, January 21, 2014. Japanese fishermen drove a large group of dolphins into the shallows and killed at least 30 on Tuesday, hiding themselves behind a tarpaulin, as the annual dolphin hunt that sparked protest in the West entered its final stages. Every year the fishermen of Taiji, in western Wakayama prefecture, drive hundreds of dolphins into a cove, select some for sale to marine parks, release some and kill the rest for meat. REUTERS/Adrian Mylne (JAPAN - Tags: ANIMALS ENVIRONMENT POLITICS)

Fishermen hunt dolphins in the shallows of a cove in Taiji, western Japan, January 21, 2014. Japanese fishermen drove a large group of dolphins into the shallows and killed at least 30 on Tuesday, hiding themselves behind a tarpaulin, as the annual dolphin hunt that sparked protest in the West entered its final stages. Every year the fishermen of Taiji, in western Wakayama prefecture, drive hundreds of dolphins into a cove, select some for sale to marine parks, release some and kill the rest for meat. REUTERS/Adrian Mylne (JAPAN - Tags: ANIMALS ENVIRONMENT POLITICS TPX IMAGES OF THE DAY)

Fishermen in wetsuits hunt dolphins at a cove in Taiji, western Japan, January 20, 2014. In an unusual move, U.S. ambassador to Japan Caroline Kennedy has expressed deep concern over the traditional dolphin hunt in western Japan, where local fisherman corral dolphins in a secluded bay before killing many for meat. The annual dolphin hunt currently underway in Taiji in western Japan has long been a source of controversy and was the topic of "The Cove," an Oscar-winning documentary. REUTERS/Adrian Mylne (JAPAN - Tags: ANIMALS ENVIRONMENT POLITICS TPX IMAGES OF THE DAY)

A resident practices Taiji, a traditional form of Chinese martial arts, at Ritan park in central Beijing, October 29, 2013. REUTERS/Jason Lee (CHINA - Tags: SOCIETY SPORT)

A group of retired people take part in a Tai Chi class session in Nice February 19, 2013. France's President will ask more of old people to fix the hole in the nations retirement coffers but tread gently in doing so. Even a softly-softly approach will mark the first time a left-wing president has dared to tamper with a system which is one of the sacred cows of France's model of generous welfare provision. A plan in the works will likely leave intact the official retirement age of 62 but trim annual pension rises, buying Hollande time to try and coax people in their 50s and 60s to work a few more years, officials working on the project say. Picture taken February 19, 2013 REUTERS/Eric Gaillard (FRANCE - Tags: SOCIETY POLITICS)

People practice Taiji on a hazy day at a local school in downtown Chongqing January 30, 2013. REUTERS/Carlos Barria (CHINA - Tags: ENVIRONMENT SOCIETY)

A resident practices Taiji, a traditional form of Chinese martial arts, at a park on a rain-snow mixed day in central Beijing, November 4, 2012. China on Sunday continued to warn against blizzards, hiking the alert to the second-highest level on snowstorms that are expected to hit northern regions over the next few days, Xinhua reported. REUTERS/Jason Lee (CHINA - Tags: ENVIRONMENT)

Britain's Prince William and his wife Catherine, the Duchess of Cambridge, watch a man practise taichi (R) during a tour in Strathmore Green at Queenstown public housing estate in Singapore September 12, 2012. The royal couple is in the city-state for a three-day visit that started on Tuesday as part of a tour to mark Queen Elizabeth II's Diamond Jubilee. REUTERS/Nicolas Asfouri/Pool (SINGAPORE - Tags: POLITICS ROYALS ENTERTAINMENT)

Activists protest against the annual slaughter of dolphins in the fishing village of Taiji in Japan, in front of the Japanese embassy in San Jose August 31, 2012. They are taking part in a global campaign for Japan Dolphin Day to raise awareness about the country's dolphin hunting season which begins on September 1. The placards read, "A day of dolphins in Japan" (R) and "Yes to life, no more killings in Japan". REUTERS/Juan Carlos Ulate (COSTA RICA - Tags: ANIMALS CIVIL UNREST ENVIRONMENT POLITICS)

An activist fastens his signature written on dolphin-shaped origami on a banner, in protest against the annual slaughter of dolphins in the fishing village of Taiji in Japan, in front of the Japanese embassy in San Jose August 31, 2012. The activists are taking part in a global campaign for Japan Dolphin Day to raise awareness about the country's dolphin hunting season which begins on September 1. REUTERS/Juan Carlos Ulate (COSTA RICA - Tags: ANIMALS CIVIL UNREST ENVIRONMENT POLITICS TPX IMAGES OF THE DAY)

An activist protests against the annual slaughter of dolphins in the fishing village of Taiji in Japan, in front of the Japanese embassy in San Jose August 31, 2012. The activists are taking part in a global campaign for Japan Dolphin Day to raise awareness about the country's dolphin hunting season which begins on September 1. The placards reads, "Put an end to the slaughter". REUTERS/Juan Carlos Ulate (COSTA RICA - Tags: ANIMALS CIVIL UNREST ENVIRONMENT POLITICS)

Activists protest against the annual slaughter of dolphins in the fishing village of Taiji in Japan, in front of the Japanese embassy in San Jose August 31, 2012. They are taking part in a global campaign for Japan Dolphin Day to raise awareness about the country's dolphin hunting season which begins on September 1. The placards read, "A day of dolphins in Japan" (R) and "Yes to life, no more killings in Japan". REUTERS/Juan Carlos Ulate (COSTA RICA - Tags: ANIMALS CIVIL UNREST ENVIRONMENT POLITICS)

Activists protest against the annual slaughter of dolphins in the fishing village of Taiji in Japan, in front of the Japanese embassy in San Jose August 31, 2012. They are taking part in a global campaign for Japan Dolphin Day to raise awareness about the country's dolphin hunting season which begins on September 1. The placard reads,"For a sea less red". REUTERS/Juan Carlos Ulate (COSTA RICA - Tags: ANIMALS CIVIL UNREST ENVIRONMENT POLITICS)

A woman practices Tai Chi at the financial district of Shanghai June 6, 2012. A senior Chinese official demanded on Tuesday that foreign embassies stop issuing air pollution readings, saying it was against the law and diplomatic conventions, in pointed criticism of a closely watched U.S. embassy index. REUTERS/Carlos Barria (CHINA - Tags: ENVIRONMENT SOCIETY)

A man practices taichi during an eclipse at the Bund along the Huangpu River in Shanghai May 21, 2012. The sun and moon aligned over the earth in a rare astronomical event - an annular eclipse that dimmed the skies over parts of Asia and North America, briefly turning the sun into a blazing ring of fire. REUTERS/Aly Song (CHINA - Tags: ENVIRONMENT TPX IMAGES OF THE DAY)

Residents practise Taiji, or shadow boxing, as they follow the moves of an instructor (front R) in central Beijing April 14, 2012. REUTERS/Barry Huang (CHINA - Tags: SOCIETY)

Residents practice Taiji, a traditional form of Chinese martial arts, after a snowfall at Ritan Park in central Beijing March 18, 2012. REUTERS/Jason Lee (CHINA - Tags: ENVIRONMENT)

Malaysians of ethnic Chinese descent perform tai chi exercises underneath lanterns at Thean Hou Temple in Kuala Lumpur January 17, 2012. The Lunar New Year begins on January 23 and marks the start of the Year of the Dragon, according to the Chinese zodiac. REUTERS/Samsul Said (MALAYSIA - Tags: SOCIETY TPX IMAGES OF THE DAY)

A resident practices Taiji, a traditional form of Chinese martial arts, next to a pet dog outside a temple in central Beijing December 27, 2011. REUTERS/Jason Lee (CHINA - Tags: SOCIETY ANIMALS)

A child holds up a cut-out of a dolphin during a protest in front of the Japanese embassy in Buenos Aires September 1, 2011. The activists are protesting the hunting of dolphins and whales in a small fishing village in Taiji, Japan every September, according to the activists. REUTERS/Enrique Marcarian (ARGENTINA - Tags: ANIMALS POLITICS CIVIL UNREST)

An animal rights activist holds a cut-out of a dolphin during a protest in front of the Japanese embassy in Buenos Aires September 1, 2011. The activists are protesting the hunting of dolphins and whales in a small fishing village in Taiji, Japan every September, according to the activists. REUTERS/Enrique Marcarian (ARGENTINA - Tags: ANIMALS POLITICS CIVIL UNREST)

An animal rights advocate wearing a mask, displays a placard during a protest in front of the Japanese embassy in Manila, September 1, 2011. The activists are protesting the hunting of dolphins and whales in a small fishing village in Taiji, Japan every September, according to their press statement. REUTERS/Romeo Ranoco (PHILIPPINES - Tags: POLITICS CIVIL UNREST ANIMALS)

Animal rights advocates wearing dolphin hats display placards during a protest in front of the Japanese embassy in Manila September 1, 2011. The activists are protesting the hunting of dolphins and whales in a small fishing village in Taiji, Japan every September, according to their press statement. REUTERS/Romeo Ranoco (PHILIPPINES - Tags: POLITICS CIVIL UNREST ANIMALS)

A man practises Tai Chi with a sword at Singapore's East Coast Park April 12, 2011. REUTERS/Tim Chong (SINGAPORE - Tags: SOCIETY)

Chinese Premier Wen Jiabao (C) practises tai chi with local residents at a park in Macau November 14, 2010. Wen is on a two-day visit to take part in the opening ceremony of the third Ministerial Conference of the Forum for Economic and Trade Cooperation between China and Portuguese-speaking Countries. REUTERS/Tyrone Siu (CHINA - Tags: POLITICS SPORT ODDLY IMAGES OF THE DAY)

People practise tai chi, a Chinese martial art, during morning exercises at Longtan Park in Beijing September 13, 2010. REUTERS/Grace Liang (CHINA - Tags: SOCIETY)

Participants perform Taiji, a traditional form of Chinese martial arts, during a public fitness activity at the Olympic Central Park in Beijing August 14, 2010. REUTERS/Jason Lee (CHINA - Tags: HEALTH SOCIETY SPORT)

Participants perform Qigong, a traditional form of Chinese martial arts, during a public fitness activity at the Olympic Central Park in Beijing August 14, 2010. REUTERS/Jason Lee (CHINA - Tags: HEALTH SOCIETY SPORT)

Participants perform Taiji, a traditional form of Chinese martial arts, during a public fitness activity at the Olympic Central Park in Beijing August 14, 2010. REUTERS/Jason Lee (CHINA - Tags: SOCIETY SPORT HEALTH)

People practice Tai-Chi as "Paris Plages" (Paris Beach) opens along the banks of the River Seine in Paris July 20, 2010. The beach atmosphere, on the banks of the Seine in central Paris and the Bassin de la Villette, includes a swimming pool overlooking the Seine, stretches of imported sand and various free sporting and cultural activities for the public. REUTERS/Philippe Wojazer (FRANCE - Tags: SOCIETY TRAVEL)

Taiji enthusiasts take part in their daily taiji practice on the top of Cuihua mountain, on the outskirts of Xian, Shaanxi province July 5, 2010. Picture taken July 5, 2010. REUTERS/Rooney Chen (CHINA - Tags: SOCIETY SPORT IMAGES OF THE DAY)

A man practices Tai Chi during an early morning session at the Bund, on the banks of the Huangpu River, following its reopening after a massive renovation for the upcoming Shanghai World Expo 2010 in Shanghai March 29, 2010. Shanghai underwent a massive facelift for the coming Shanghai World Expo due to start on May 1, 2010. The Oriental Pearl tower is seen in the background. REUTERS/Nir Elias (CHINA - Tags: BUSINESS SOCIETY IMAGES OF THE DAY)

People take part in an attempt to break the Guinness World Record for the largest number of people practising Taiji in multiple locations, at the Shenyang Olympic Sports Center, to mark the one-year anniversary of the Beijing Olympic Games in Shenyang, Liaoning province August 8, 2009. REUTERS/Sheng Li (CHINA)

People take part in an attempt to break the Guinness World Record for the largest number of people practising Taiji in multiple locations, at the Shenyang Olympic Sports Center, to mark the one-year anniversary of the Beijing Olympic Games in Shenyang, Liaoning province August 8, 2009. REUTERS/Sheng Li (CHINA HEALTH SOCIETY IMAGES OF THE DAY SPORT)

A resident wearing a raincoat practises Taiji in the rain during an event to mark the one-year anniversary of the Beijing Olympic Games, outside the National Olympic Stadium, also known as the Bird's Nest, in Beijing August 8, 2009. REUTERS/Jason Lee (CHINA SOCIETY SPORT)

People arrive to take part in an attempt to break the Guinness world record for the largest number of people practising Taiji in multiple locations, outside the National Olympic Stadium, also known as the Bird's Nest, to mark the one-year anniversary of the Beijing Olympic Games in Beijing August 8, 2009. REUTERS/Jason Lee (CHINA SOCIETY SPORT)