Nearly four full years have passed since the cauldron was extinguished at the 2018 PyeongChang Winter Olympics, and now the 2022 Games are almost upon us.

But while the Winter Olympics have been on a hiatus, the winter sports world has not. A lot has happened in the last four years as new stars emerged, PyeongChang champions continued their ascents, and a global pandemic touched every corner of society.

Before Beijing 2022 begins, get caught up on what you've missed since the PyeongChang Games with some of the biggest stories of the last few years covered below.

The 2018 Winter Olympics saw Shaun White and Chloe Kim sweep the men's and women's snowboard halfpipe events for Team USA. But since then, both riders have rarely been seen in a halfpipe.

After the last Winter Olympics, White was absent from snowboarding contests for more than three years. He considered making a run at qualifying for skateboarding at the Tokyo Olympics — he even competed at skateboarding's 2019 World Championships — but decided to end his bid in 2020. White returned to snowboard competition in March 2021 for the first of several U.S. Olympic qualifying events, and although he finished in fourth place, he was the top American in the contest.

One of White's primary rivals, two-time Olympic silver medalist Ayumu Hirano of Japan, also took a break from snowboarding. During his time off, he did successfully qualify for Olympic skateboarding and finished 14th in men's park. In the absences of White and Hirano, Japan's Yuto Totsuka and Australia's Scotty James were the top contest riders in men's halfpipe.

The returns of White and Hirano aren't all that's new this year. Triple corks have officially entered the scene, as three Japanese riders — Totsuka, Ayumu Hirano and Ruka Hirano (no relation) — all landed the trick in a halfpipe at a pre-season training camp. In December, Ayumu Hirano became the first rider to land it in a competition, setting the stage for what looks to be a very progressive season.

As for Kim, she took some time off following the 2018/19 season and enrolled at Princeton University. While spending her freshman year on campus, she was able to use that time to heal a broken ankle and disconnect from snowboarding and competition. The time away from the sport helped rekindle Kim's passion for it, and she returned to the circuit in January 2021 after a 22-month break. Currently on a leave of absence from Princeton, Kim picked up right where she left off, winning X Games and all other events she entered last year. The 21-year-old remains the gold medal favorite in women's halfpipe.

Nathan Chen entered the 2018 Winter Olympics as a gold medal contender in men's figure skating, but he struggled during his short program and ultimately finished off the podium. Since then, he's been practically unbeatable.

Nearly four years have passed since Chen finished fifth in PyeongChang, and during that time, he did not lose a single competition he entered until a recent third-place finish, behind fellow American Vincent Zhou and Japan's Shoma Uno, at Skate America in October 2021. His undefeated run until then included three straight world titles, three straight national titles (bringing his overall streak to five straight) and multiple wins over two-time Olympic champion Yuzuru Hanyu of Japan. Chen, now 22, is a master of the quad — he landed six of them during his free skate in PyeongChang — and the favorite for Olympic gold in men's figure skating.

The last few seasons for U.S. Alpine star Mikaela Shiffrin have had their ups and downs. On the snow, the biggest development is that Shiffrin — long known for her prowess in the technical events (slalom, giant slalom) — has become a major threat in the speed events (downhill, super-G) as well. She won her first downhill World Cup race in December 2017, then won her first super-G a year later, making her just the 12th skier to win World Cup races in all five major disciplines. Her historic 2018/19 season also included gold at the world championships in super-G and four World Cup titles, including her third straight overall title and her first-ever titles for super-G and giant slalom. It remains to be seen which events Shiffrin will contest in Beijing but she has expressed a desire to enter all five.

Unfortunately, Shiffrin's record-breaking season was followed by the tragic and unexpected death of her father in February 2020. Shiffrin left the World Cup circuit for several weeks after his passing and when she planned to return, the rest of the season was cancelled due to the pandemic. She would not race again until November 2020 — after a 10-month hiatus — but ended the 2020/21 season ranked No. 2 in both of the technical disciplines and won four medals at the world championships. Her win in the super combined gave her the sixth world title of her career, breaking the all-time American record.

Jessie Diggins provided one of the most iconic moments from the 2018 Winter Olympics when she partnered with Kikkan Randall in the team sprint to win Team USA's first-ever gold medal in cross-country skiing. Randall retired after the PyeongChang Games, but Diggins, now 30, has continued making history.

The 2020/21 season was Diggins' most successful yet. In January, she became the first American to win the Tour de Ski, a cross-country event with multiple stages based on the Tour de France format. She then capped off the season by becoming the first U.S. woman to win the World Cup overall title. Those performances have helped solidify Diggins as a medal contender, though the historically strong Norwegian team — which skipped the Tour de Ski and several World Cup races due to the pandemic — will be expected to perform well in Beijing.

Jessie Diggins captured her first Tour de Ski title in January 2021.

Getty Images

In freeskiing, it's rare to find "triple threats" — athletes who excel in all three disciplines (halfpipe, slopestyle, big air) — but a pair of teenagers, 19-year-old Kelly Sildaru and 18-year-old Eileen Gu, have been taking over women's contests by doing just that.

Estonia's Sildaru, who exploded onto the slopestyle scene at age 13, was set up to be a breakout star at the 2018 Winter Games, but a torn ACL prevented her from competing in PyeongChang. After recovering from that injury, Sildaru quickly returned to her winning ways and established herself as a threat not just in slopestyle, but also in halfpipe and big air, as she collected three gold medals, one silver and one bronze at Winter X Games in 2019 and 2020.

Gu made her X Games debut in 2021 — a year Sildaru was absent due to injury — and had a true breakout performance as she won gold in halfpipe and slopestyle, plus bronze in big air. Although she was born in San Francisco and grew up in the United States, Gu became a naturalized Chinese citizen in 2019 and now competes for her mother's home country. She could become one of the host nation's biggest stars at Beijing 2022.

Both skiers also won gold medals at the Youth Olympic Games in 2020 — Sildaru in slopestyle, Gu in halfpipe and big air — and now they could compete across multiple events for Winter Olympic gold.

China's Eileen Gu (center) won gold in freeski halfpipe at the 2020 Winter Youth Olympics — one of three medals overall she won at those Games.

USA TODAY Sports

Following Team USA's dramatic shootout win over Canada at the 2018 Winter Olympics, the two countries have remained at the forefront of women's hockey. The United States won gold at the 2019 World Championships but Canada bounced back in 2021, overcoming a first-period deficit to defeat the Americans in overtime and win its first world or Olympic title since 2014. The two teams are set to renew their rivalry in Beijing. While Jocelyne Lamoureux-Davidson and Monique Lamoureux-Morando, two of the stars from the 2018 Olympics, have retired, Team USA will return a number of key players including Kendall Coyne Schofield, Brianna Decker and Hilary Knight.

As for the men's tournament, there was a lot of excitement around the NHL's decision allowing its players to participate in the Olympics for the first time since 2014. Those plans were scrapped in December, though, after a surge in COVID cases disrupted the league's schedule. In a statement, NHL commissioner Gary Bettman said that Olympic participation was "no longer feasible" given that disruption.

After a surprising gold medal win in the men's tournament at PyeongChang 2018, the United States has not been able to replicate that sort of result at major tournaments. Instead it's been Sweden that has won all three men's world titles awarded since the last Olympics.

The American team led by John Shuster remains mostly intact and has represented the U.S. at recent world championships. Shuster's team will attempt a title defense in Beijing after winning U.S. Olympic Trials once again.

The bobsled landscape shifted in 2019 when Kaillie Humphries announced her intention to switch from Canada to the United States. Citing claims of verbal and emotional abuse from a former coach, Humphries — who is married a married to an American former bobsledder — was eventually granted her release from the Canadian program and allowed to train with the U.S. team. Her results since then have been stellar, as she piloted the U.S. to a pair of world titles in the two-woman bobsled (partnered with Lauren Gibbs in 2020 and Lolo Jones in 2021), and she also won the inaugural world title in women's monobob, a new event that will debut on the Olympic program in Beijing.

The one complication for Humphries: In order for her to compete at the Olympics, she needed to officially obtain U.S. citizenship. It was uncertain whether that would happen in time for her to compete at the Winter Games, but in December, she was finally sworn in as a citizen. With her Olympic status now settled, Humphries — who has two gold medals (2010, 2014) and one bronze medal (2018) in the two-woman bobsled — will be among the favorites in both women's events along with fellow U.S. pilot Elana Meyers Taylor, herself a three-time Olympic medalist.

For sport-by-sport looks at what you've missed in the last four years, check out the articles below: