Lee made his debut in ISU events in 1992 at age 13, when he competed at the World Junior Championships in Warsaw.
He did not qualify for the final distance, but his samalog total ranked him as 21st of 49 competitors and the second best from South Korea.
He returned the following year but again failed to qualify, though he improved two places and was the best Korean after Bong Ju-hyeon got disqualified in the 1,500 meters.
At the World Junior Championships in Calgary, however, Lee qualified for the final distance for the first time and finished fourth overall, 0.098 points behind the bronze medalist.
Lee also finished fourth at the Junior Championships in 1995 and 1996, losing his lead after the opening three distances to long-distance specialists Bob de Jong and Mark Knoll.
Nevertheless, he was selected to represent South Korea at the 1995 World Championships all round, where he finished fourth on the 500 meters but still failed to qualify for the final distance, ending as 20th.
While still a world record holder, he won silver at the Asian Single Distance Championships in Obihiro, only beaten by fellow Korean Kim Yun-Man.
At the Asian Winter Games, he won silver on the 1,000 meters, but that tournament lacked the participation of the best Japanese skaters such as Hiroyasu Shimizu, Junichi Inoue and Yukinori Miyabe, who all beat Lee at the World Cup in Nagano.
In March, he rounded off the season with fourth and fifth place at the World Single Distance Championships in the Utah Olympic Oval.
The record stood for almost a year until Derek Parra beat it at the 2002 Winter Olympics in Salt Lake City.
In Heerenveen in January, however, he won his first World Cup race in four years, sharing the win with Gerard van Velde, whose last-pair effort was good enough to tie with Lee's time.
A week later, Lee recorded his best placing at a World Sprint championship, though he finished sixth and further behind the winner than he had been the previous year.
In January, he had repeated last season's sixth place in the World Sprint Championships, though the distance to winner Wotherspoon grew to 1.8 points, and at the Asian Winter Games in Aomori, he won gold on both the 1000 and 1500 metre event, pipping Hiroyasu Shimizu by 0.05 seconds on the 1000 metres.
He could not repeat the performance in the remainder of the season, with two ninth-placings in Calgary as best, and finished 15th in the overall 1000 metre World Cup.
Lee took part in his fourth Olympic Games in Turin, and showed strength by winning a 1000-metre test race in Calgary in 1:08.77, close to his personal best.
He then won a 500-metre race in Berlin Sportforum, thus taking the lead in both sprint distance cups before the sprinters travelled to Asia.
However, Lee lost less on the second day's 500 metre race, and set Koskela the challenge of repeating his time from Saturday to become World Sprint Champion.
Koskela arrived 0.13 seconds too late, leaving Lee as the third South Korean world sprint champion, despite not winning a single distance.
Shani Davis, who finished third in the World Cup standings after skipping four of nine meets, also had three wins and beat Lee in four of six races in the season.
Lee finished off the season with two appearances at the World Single Distance Championships in Utah Olympic Oval.
In the first World Cup race of the season, at the Utah Olympic Oval, Lee skated a new personal best mark with 34.31 seconds, just 0.01 seconds behind the world record before that race, yet was beaten both by compatriot Lee Kang-seok, who thus took the Korean national record, and Jeremy Wotherspoon, who had returned after a 365-day absence.
Lee then missed out on Sunday's 1000 metre victory by 0.04 seconds, and despite lowering his personal best to 1:07.07, he ended in third place, advancing to fourth on the all-time list and a Korean record.
Lee picked up podium spots on the 500 m in Heerenveen and Erfurt, and had three successive third-place appearances on the 1000 m, starting with the race in Calgary.
He was one of few disappointments in a strong Korean team, which topped the medal table in speed skating; teammate Mo Tae-bum, who had skipped the Obihiro championship, won the 500 m gold.