1. Overview
Eriko Asai (浅井 えり子Asai ErikoJapanese), born on October 20, 1959, is a retired long-distance runner and coach from Japan. Standing at 59 in (150 cm) and weighing 88 lb (40 kg), she is recognized for her significant contributions to Japanese women's marathon running, including winning the gold medal at the 1986 Asian Games in Seoul, South Korea, and achieving victory at the 1994 Nagoya Women's Marathon. Asai represented Japan at the 1988 Summer Olympics in Seoul and later transitioned into coaching, promoting the "Long Slow Distance (LSD)" theory. Beyond her athletic career, she has held academic and educational roles, contributing to the development of sports and community education.
2. Early Life and Education
Eriko Asai was born in Adachi, Tokyo, Japan. Her journey into track and field began during her high school years at Tokyo Metropolitan Adachi High School, where she joined the track and field club at the invitation of a friend. Despite her participation, she did not achieve particularly notable results during her high school career. After graduating, Asai continued her education at Bunkyo University, where she once again joined the university's track and field club. It was during her third year at Bunkyo University, in November 1980, that she made her debut in the marathon at the 2nd Tokyo International Women's Marathon. She completed the race in 12th place with a time in the 3-hour range, marking her first experience in the demanding long-distance event. While at Bunkyo University, Asai was coached by Yoko Kajiwara, who later became a well-known commentator on women's long-distance running and marathons.
3. Athletic Career
Eriko Asai's professional running career saw her rise to prominence in the Japanese long-distance running scene, characterized by significant victories, Olympic participation, and enduring dedication despite numerous challenges.
3.1. Joining NEC-HE and Early Success
In April 1982, following her graduation from university, Eriko Asai joined NEC Home Electronics (NEC-HE), then known as Shin Nippon Electric. She became part of the company's track and field club, which at the time comprised only male members; Asai was the sole female athlete on the team. Under the guidance of coach Isao Sasaki, she began to distinguish herself in women's marathon running. Her early performances included the March 1984 Nagoya Women's Marathon, a selection race for the 1984 Summer Olympics in Los Angeles. Asai finished 4th overall with a time of 2:38, making her the highest-placed Japanese runner. However, she was not selected for the Los Angeles Olympics, as the selectors perceived a significant gap in performance between her and leading Japanese runners like Akemi Masuda and Nanae Sasaki.
Later that year, in November 1984, Asai achieved a significant milestone at the Tokyo International Women's Marathon, where she placed 2nd behind Kathrin Dörre of East Germany. Her time of 2:33 established her as the then second-fastest Japanese woman in marathon history. Following this, both Akemi Masuda and Nanae Sasaki retired from competitive running, which positioned Asai as a leading figure in Japanese women's long-distance running and marathon. Despite the increased media attention, Asai, wary of constant interviews, reportedly stated, "I'm not a talent, so I don't want to be interviewed repeatedly."
3.2. Asian Games Gold Medal and Olympic Participation
Eriko Asai earned her first opportunity to represent Japan at an international championship in April 1985, when she competed in the World Cup marathon in Hiroshima. Although she was the top Japanese finisher, she placed 9th overall. In January 1986, she secured a runner-up position at the Osaka International Women's Marathon, finishing behind Lorraine Moller. Her breakthrough came in October of the same year at the 1986 Asian Games in Seoul, South Korea. Competing alongside her Japanese teammate Misako Miyahara, Asai surged ahead in the late stages of the race to claim her first marathon victory, earning the gold medal. Despite a modest winning time of 2:41:03, her triumph made her the inaugural women's marathon champion at the Asian Games.
Following her Asian Games success, Asai continued to compete internationally. She was selected to represent Japan at the 1987 World Championships in Athletics in Rome, Italy, where she finished 26th in the marathon with a time of 2:48:44. She also participated in several Yokohama International Ekiden races as a member of the Japanese national team. Despite these consistent performances, the anticipated breakthrough of achieving a sub-2:30 marathon time, a major goal for Japanese women runners, remained elusive, and her best times had not surpassed her 1984 Tokyo International performance.
The lead-up to the 1988 Summer Olympics in Seoul was a critical period for Asai. In January 1988, she competed in the Osaka International Women's Marathon, which served as a qualifier for the Olympic Games. During the latter half of the race, around the 30-kilometer mark, Asai engaged in a fierce contest with Misako Miyahara. However, Miyahara made a strong surge past 35 kilometers, leaving Asai behind. Further into the race, near the 41-kilometer mark, Kumi Araki also overtook Asai, causing her to drop to 4th place. Exhausted, Asai stumbled and fell just before the finish line. Miyahara's performance resulted in the first sub-2:30 time by a Japanese woman, and both Miyahara and Araki were provisionally selected for the Olympic team.
The final third spot on the Olympic team was then a contention between Asai and Kazue Kojima, who had finished 8th at the Tokyo International Women's Marathon in November 1987. In March 1988, at a board meeting of the Japan Association of Athletics Federations, Eriko Asai was ultimately selected for her first Olympic appearance, with Kojima designated as an alternate. In the actual 1988 Summer Olympics women's marathon in September 1988, Asai finished as the top Japanese runner, securing 25th place with a time of 2:34:41. This was in contrast to her performance at the domestic qualifier, the Osaka International Women's Marathon. However, having suffered from a decline in physical condition a few weeks before the Seoul Olympics, Asai was not mentally at her best, and she was largely out of contention for a medal or a top-8 finish. All three Japanese female athletes, including Araki (28th) and Miyahara (29th), collectively realized the significant gap that still existed between their performances and those of the world's elite marathoners.
3.3. Achieving Personal Best and Major Victories
After the Seoul Olympics, as Eriko Asai approached her late twenties and early thirties, she encountered a challenging period marked by injuries and a slump in form. She suffered from sciatica and struggled with the immense pressure to outperform younger athletes, which often led to counterproductive efforts. Consequently, she experienced a prolonged period of poor results in marathons. When Misako Miyahara and Kazue Kojima, both former Japanese women's marathon record holders, successively retired in 1989, the media frequently speculated about Asai's impending retirement.
Despite these challenges, Asai continued to compete. In January 1992, at the Osaka International Women's Marathon, a qualifier for the 1992 Summer Olympics in Barcelona, she faded in the latter half of the race and finished a disappointing 13th. However, just two months later, in March 1992, she entered the Nagoya International Women's Marathon as a general participant. She competed for the win until the very end, finishing 3rd and improving her personal best marathon record for the first time in four years, though she still missed out on Olympic selection.
At 33 years old, in the March 1993 Nagoya International Women's Marathon, Asai achieved a significant breakthrough. In her 30th full marathon, she crossed the finish line in 4th place with a time of 2:28:22, her personal best and her first time breaking the 2:30 barrier, a long-standing goal. Later that year, in July, she won the Gold Coast Marathon in Australia with a time of 2:29:29, setting a new course record at the time. Reflecting on this period, Asai noted that her Olympic non-selection had paradoxically "freed her from pressure," allowing her to approach races with a more "calm mind."
Her peak performance arrived in March 1994 at the Nagoya International Women's Marathon. The race unfolded under challenging conditions with strong winds, leading to a slow pace among the leading group. Asai remained in contention for the victory throughout. In the latter half of the race, she engaged in a fierce battle with Ramila Burangurova of Russia. Nearing the 40-kilometer mark, Asai launched a decisive move, pulling away from Burangurova. She went on to secure her first victory in one of Japan's three major international women's marathons (Tokyo, Osaka, and Nagoya). At 34, considered an advanced age for marathon running, Asai expressed immense joy in her post-race interview, stating, "I'm truly glad I kept running."
3.4. Challenges and Continued Dedication
Eriko Asai's career was profoundly shaped by both personal and professional challenges, most notably the illness and death of her coach and husband, Isao Sasaki. In June 1994, Sasaki began experiencing severe symptoms including fever, loss of appetite, and drastic weight loss. Despite repeated pleas from Asai and others to seek medical attention, Sasaki steadfastly refused. However, during a training camp in Hokkaido in August of the same year, Sasaki could no longer endure severe back and hip pain, leading to his emergency hospitalization at Tokyo Jikei University Hospital's Third Hospital in Komae, Tokyo.
Tests revealed that a form of skin cancer, malignant melanoma, had extensively metastasized throughout his body, and he was given only a few months to live. In light of this devastating diagnosis, Asai and Sasaki formalized their relationship, marrying and holding a wedding ceremony in September 1994. Following chemotherapy, Sasaki's condition temporarily improved, allowing him to be discharged from the hospital. In December 1994, he was well enough to travel with Asai to the Honolulu Marathon, which they treated as their honeymoon. However, his recovery was not complete.
Sasaki's health deteriorated again in January 1995, and he was re-hospitalized on February 2. While nursing him, Asai still competed, participating in the Miura International Citizen's Marathon (a half marathon and sister race to Honolulu) in Kanagawa Prefecture on March 5. Tragically, despite Asai's dedicated care and fervent hopes for his recovery, Isao Sasaki passed away on March 13, 1995, at the age of 52, due to malignant melanoma. His death was a deeply personal and professional loss for Asai.
Her first race after Sasaki's passing was the Honolulu Marathon in December 1995. Despite a difficult race where she stopped mid-course, she finished 9th with a time of 2:56:43. In March 1996, Asai returned to the Nagoya International Women's Marathon, which served as a qualifier for the 1996 Summer Olympics in Atlanta. At 36 years old, she finished 14th with a time of 2:33:02. This race marked her final competition as a member of the NEC-HE track and field team, as the club was disbanded that same month. Even after this, Asai continued to actively participate in marathons, including the Tokyo Marathon, Nagano Marathon, and Honolulu Marathon, continuing her career as a marathon runner well into the 2020s.
4. Post-Athletic Career and Contributions
After her primary competitive career, Eriko Asai has remained deeply involved in the world of running and has expanded her contributions into academic and educational spheres.
4.1. Coaching and Advisory Roles
Following the passing of her coach and husband, Isao Sasaki, Eriko Asai took on the mantle of his legacy, particularly in promoting his coaching philosophy, the "Long Slow Distance (LSD)" theory. Sasaki, who had guided Asai for 13 years, introduced the concept of running "slowly, for a long distance, over time" to the Japanese marathon community. This theory posits that by running slowly, one can activate dormant capillaries in the body, thereby enhancing athletic capability. Its slogan, "Run slowly, become fast," significantly influenced numerous citizen runners. Asai has since continued Sasaki's work, leading running classes, delivering lectures, and serving as a coach. She specifically focuses on the LSD theory in her guidance, making it a cornerstone of her coaching activities. She also serves as an adviser for the women's Ekiden team at Teikyo University of Science.
4.2. Academic and Educational Activities
Eriko Asai's engagement extends beyond direct coaching into academic and broader educational fields. She holds a position as a visiting professor at Teikyo University of Science. In 1996, she became a visiting researcher at the Education Research Institute of her alma mater, Bunkyo University. In this capacity, she co-authored a scholarly paper with her former university coach, Yoko Kajiwara, focusing on the health and physiological aspects of female long-distance runners. Furthermore, Asai contributes to local governance and education as a member of the education committee in Adachi Ward, her hometown in Tokyo.
5. Publications
Eriko Asai has authored several books, sharing her experiences, insights, and coaching philosophy, particularly the "Long Slow Distance (LSD)" theory.
- もういちど二人で走りたいMo Ichido Futari de HashiritaiJapanese (I Want to Run Together Again) - Published by Tokuma Shoten on November 1, 1995. This book likely reflects on her personal journey and her relationship with her coach, Isao Sasaki.
- 浅井えり子の「新・ゆっくり走れば速くなる」 マラソン・トレーニング改革Asai Eriko no "Shin Yukuri Hashireba Hayaku Naru" Marathon Training ReformJapanese (Eriko Asai's "New Run Slowly, Become Fast": Marathon Training Reform) - Published by R-bies on June 1, 1997. This work delves into her coaching methodology, specifically focusing on adapting and promoting the LSD theory for marathon training.
- 新版 ゆっくり走れば速くなるShinpan Yukuri Hashireba Hayaku NaruJapanese (New Edition: Run Slowly, Become Fast) - Published by R-bies on October 1, 2005. This is an updated version of her earlier work, further elaborating on the "run slowly, become fast" concept.
Additionally, a related foundational book on the LSD theory was authored by her late coach:
- ゆっくり走れば速くなるYukuri Hashireba Hayaku NaruJapanese (Run Slowly, Become Fast) - Authored by Isao Sasaki, originally published by R-bies on October 1, 1984, and re-published on June 26, 2020. This book lays out the core principles of the LSD theory that Asai later inherited and continues to promote.
6. Main Competition Results
This table summarizes Eriko Asai's key performances and placements in major international and national athletic competitions.
| Year | Competition | Location | Place | Event | Time |
|---|---|---|---|---|---|
| 1986 | 1986 Asian Games | Seoul, South Korea | 1st | Marathon | 2:41:03 |
| 1987 | 1987 World Championships in Athletics | Rome, Italy | 26th | Marathon | 2:48:44 |
| 1988 | 1988 Summer Olympics | Seoul, South Korea | 25th | Marathon | 2:34:41 |
| 1992 | IAAF World Half Marathon Championships | Newcastle, United Kingdom | 7th | Half marathon | 1:10:51 |
| 1994 | Nagoya Women's Marathon | Nagoya, Japan | 1st | Marathon | 2:30:30 |
7. Detailed Marathon Records
The following table provides a chronological list of Eriko Asai's specific marathon race results throughout her competitive history, including race names, dates, times, and rankings.
| Date | Race Name | Time | Rank | Notes |
|---|---|---|---|---|
| November 1980 | Tokyo International Women's Marathon | 3:00:32 | 12th | First marathon |
| November 1981 | Tokyo International Women's Marathon | 2:56:49 | 13th | |
| January 1982 | Osaka Women's Marathon | 2:54:26 | 19th | |
| November 1982 | Tokyo International Women's Marathon | 3:01:56 | 26th | |
| January 1983 | Osaka Women's Marathon | 2:52:23 | 21st | |
| May 1983 | Vancouver Marathon | 2:50:36 | 3rd | |
| November 1983 | Tokyo International Women's Marathon | 2:39:47 | 5th | |
| March 1984 | Nagoya Women's Marathon | 2:38:31 | 4th | 1st among Japanese competitors |
| June 1984 | Sydney Marathon | 2:43:42 | 3rd | |
| November 1984 | Tokyo International Women's Marathon | 2:33:43 | 2nd | Then 2nd fastest Japanese female time |
| January 1985 | Osaka International Women's Marathon | 2:40:11 | 9th | 1st among Japanese competitors |
| April 1985 | World Cup Hiroshima Women's Marathon | 2:37:19 | 9th | 1st among Japanese competitors |
| November 1985 | Tokyo International Women's Marathon | 2:45:24 | 14th | |
| January 1986 | Osaka International Women's Marathon | 2:34:47 | 2nd | 1st among Japanese competitors |
| October 1986 | 1986 Asian Games Marathon (Seoul) | 2:41:03 | 1st | Gold medal |
| November 1986 | Tokyo International Women's Marathon | 2:40:44 | 7th | |
| August 1987 | 1987 World Championships in Athletics Marathon (Rome) | 2:48:44 | 26th | |
| January 1988 | Osaka International Women's Marathon | 2:32:13 | 4th | |
| September 1988 | 1988 Summer Olympics Marathon (Seoul) | 2:34:41 | 25th | 1st among Japanese competitors |
| April 1989 | Boston Marathon | 2:33:04 | 4th | 1st among Japanese competitors |
| January 1990 | Osaka International Women's Marathon | 2:34:31 | 11th | |
| March 1990 | Nagoya International Women's Marathon | 2:33:40 | 3rd | |
| August 1990 | Hokkaido Marathon | 2:36:55 | 3rd | |
| January 1991 | Osaka International Women's Marathon | 2:37:24 | 13th | |
| October 1991 | Betsukai Pilot Marathon | 2:35:29 | 1st | |
| January 1992 | Osaka International Women's Marathon | 2:32:29 | 13th | |
| March 1992 | Nagoya International Women's Marathon | 2:31:42 | 3rd | |
| November 1992 | Tokyo International Women's Marathon | 2:31:41 | 5th | 1st among Japanese competitors |
| February 1993 | Ageo City Marathon | 2:34:07 | 1st | |
| March 1993 | Nagoya International Women's Marathon | 2:28:22 | 4th | Marathon personal best |
| July 1993 | Gold Coast Marathon | 2:29:29 | 1st | |
| November 1993 | Tokyo International Women's Marathon | 2:31:34 | 5th | |
| March 1994 | Nagoya International Women's Marathon | 2:30:30 | 1st | First victory in a major Japanese international marathon |
| December 1994 | Honolulu Marathon | 2:38:21 | 2nd | 1st among Japanese competitors |
| December 1995 | Honolulu Marathon | 2:56:43 | 9th | |
| March 1996 | Nagoya International Women's Marathon | 2:33:02 | 14th | |
| June 1996 | Portland Marathon | 2:40:03 | 1st | |
| December 1996 | Honolulu Marathon | 2:50:23 | 8th | |
| November 1997 | New York City Marathon | 2:45:39 | 16th | |
| January 1998 | Osaka International Women's Marathon | 2:38:47 | 20th | |
| March 1999 | Nagoya International Women's Marathon | 2:45:24 | 30th | |
| December 1999 | Honolulu Marathon | 2:46:47 | 5th | |
| January 2000 | Osaka International Women's Marathon | 2:56:09 | 50th | |
| March 2001 | Nagoya International Women's Marathon | 2:43:31 | 36th | |
| June 2001 | Gold Coast Marathon | 2:41:34 | 3rd | |
| April 2005 | Nagano Marathon | 3:00:35 | 17th | |
| February 2007 | Tokyo Marathon 2007 | 3:45:20 | 354th | |
| February 2008 | Tokyo Marathon 2008 | 4:09:38 | 921st | |
| April 2008 | Nagano Marathon | 3:28:24 | 94th | |
| March 2009 | Tokyo Marathon 2009 | 3:27:55 | 208th | |
| February 2010 | Tokyo Marathon 2010 | 3:46:27 | 364th | |
| February 2011 | Tokyo Marathon 2011 | 3:57:36 | - | |
| February 2012 | Tokyo Marathon 2012 | 3:47:34 | 472nd | |
| April 2012 | Nagano Marathon | 3:35:31 | - | Guest participant |
| February 2013 | Tokyo Marathon 2013 | 3:52:44 | - | Net time 3:48:57 |
| February 2014 | Tokyo Marathon 2014 | 4:03:22 | - | Net time 3:57:13 |
| February 2015 | Tokyo Marathon 2015 | 3:44:56 | - | Net time 3:44:54 |
| February 2016 | Tokyo Marathon 2016 | 4:10:55 | - | Net time 4:06:44 |
| February 2017 | Tokyo Marathon 2017 | 3:58:35 | - | Net time 3:54:39 |
8. Legacy and Influence
Eriko Asai's lasting impact on Japanese long-distance running extends beyond her impressive competitive record. A significant part of her legacy is her dedication to popularizing and continuing the "Long Slow Distance (LSD)" theory, which was introduced by her late coach and husband, Isao Sasaki. Sasaki's innovative approach, emphasizing consistent, slow-paced long runs to enhance endurance and capillary development, became a foundational concept for many Japanese runners. After his death, Asai took on the vital role of inheriting and actively promoting this theory. Through her coaching and public speaking engagements, she has educated and inspired countless citizen runners and aspiring athletes, spreading the message that "running slowly leads to becoming faster."
Her perseverance throughout her career, particularly her ability to overcome injuries, slumps, and personal tragedy to achieve a personal best at 33 and a major victory at 34, serves as an inspiring example of enduring dedication in sport. Asai's continued involvement in running, even decades after her peak competitive years, further solidifies her influence on the sport's community in Japan. Her academic contributions, including her work on the health and physiology of female long-distance runners at Bunkyo University and her role in the Adachi Ward education committee, also demonstrate her broader commitment to well-being and development within and beyond athletics.