# Kazuma Ōseto

Kazuma Ōseto (大瀬戸一馬, Ōseto Kazuma, born 5 August 1994) is a Japanese sprinter.
He won a silver medal in the 100 m at the 2011 World Youth Championships in Athletics, behind Odail Todd.

## Personal bests

| Event | Time | Wind | Venue | Date |
| Outdoor |||||
| 100 m | 10.19 s | +1.7 m/s | Hiratsuka, Japan | 11 June 2016 |
| 200 m | 20.55 s | +0.6 m/s | Yokohama, Japan | 22 May 2016 |
| Indoor |||||
| 60 m | 6.71 s | | Osaka, Japan | 2 February 2013 |

## Records

* 100 metres
** Former Japanese junior and Japanese high school record holder - 10.23 s (wind: +1.3 m/s) (Hiroshima, 29 April 2012)
* 4×100 m relay
** Current Asian and Japanese junior record holder - 39.01 s (relay leg:1st) (Barcelona, 13 July 2012)
** Current Japanese university record holder - 38.44 s (relay leg:4th) (Tianjin, 9 October 2013)
** Current Japanese high school record holder - 39.16 s (relay leg: 1st) (Fukuroi, 3 May 2012)
* Medley relay (100m×200m×300m×400m)
** Former Japanese youth best holder - 1:50.69 s (relay leg: 1st) (Lille, 10 July 2011)
* 60 metres (Indoor)
** Former Japanese junior record holder - 6.71 s (Osaka, 2 February 2013)
    $^a$ with Akiyuki Hashimoto, Asuka Cambridge, and Kazuki Kanamori
    $^b$ with Ryōta Yamagata, Shōta Iizuka, and Asuka Cambridge
    $^c$ with Akiyuki Hashimoto, Tatsurō Suwa, and Kazuki Kanamori
    $^d$ with Akiyuki Hashimoto, Shōtarō Aikyō, and Takuya Fukunaga

## Competition record

| Year | Competition | Venue | Position | Event | Notes |
| Representing Japan ||||||
| 2011 | World Youth Championships | Lille, France | 2nd | 100 m | 10.52 (wind: -0.3 m/s) |
| 2011 | World Youth Championships | Lille, France | 2nd | Medley relay | 1:50.69 (relay leg: 1st) NYB |
| 2012 | World Junior Championships | Barcelona, Spain | 16th (sf) | 100 m | 10.56 (wind: -0.5 m/s) |
| 2012 | World Junior Championships | Barcelona, Spain | 3rd | 4×100 m relay | 39.02 (relay leg: 1st) |
| 2013 | Asian Championships | Pune, India | 2nd | 4×100 m relay | 39.11 (relay leg: 2nd) |
| 2013 | East Asian Games | Tianjin, China | 3rd | 100 m | 10.48 (wind: -0.1 m/s) |
| 2013 | East Asian Games | Tianjin, China | 1st | 4×100 m relay | 38.44 (relay leg: 4th) GR, NUR |
| 2014 | World Relays | Nassau, Bahamas | 5th | 4×100 m relay | 38.40 (relay leg: 1st) |
| 2014 | Continental Cup | Marrakech, Morocco | 4th | 4×100 m relay | 39.50 (relay leg: 1st) |
| 2015 | World Relays | Nassau, Bahamas | 3rd | 4×100 m relay | 38.20 (relay leg: 1st) |
| 2015 | Asian Championships | Wuhan, China | 9th (sf) | 100 m | 10.45 (wind: +0.8 m/s) |
| 2015 | Asian Championships | Wuhan, China | 3rd | 4×400 m relay | 3:03.47 (relay leg: 3rd) |
| 2015 | Universiade | Gwangju, South Korea | 1st | 4×100 m relay | 39.08 (relay leg: 1st) |
| 2015 | World Championships | Beijing, China | 10th (h) | 4×100 m relay | 38.60 (relay leg: 1st) |

### National Championship

| Year | Competition | Venue | Position | Event | Notes |
| 2013 | Japan Championships | Chōfu, Tokyo | 6th | 100 m | 10.36 (wind: +0.7 m/s) |
| 2013 | Japan Championships | Yokohama, Kanagawa | 3rd | 4×100 m relay | 39.57 (relay leg: 2nd) |
| 2014 | Japan Championships | Fukushima, Fukushima | 4th | 100 m | 10.35 (wind: +0.6 m/s) |
| 2014 | Japan Championships | Yokohama, Kanagawa | 1st | 4×100 m relay | 38.81 (relay leg: 2nd) GR |
| 2015 | Japan Championships | Niigata, Niigata | 8th | 100 m | 10.55 (wind: -0.9 m/s) |
| 2015 | Japan Championships | Yokohama, Kanagawa | 1st | 4×100 m relay | 38.79 (relay leg: 2nd) GR |
| 2016 | Japan Championships | Nagoya, Aichi | 4th | 100 m | 10.41 (wind: -0.3 m/s) |
| 2016 | Japan Championships | Nagoya, Aichi | 5th | 200 m | 20.72 (wind: +1.8 m/s) |
| 2016 | Japan Championships | Yokohama, Kanagawa | 1st | 4×100 m relay | 38.89 (relay leg: 2nd) |
| 2017 | Japan Championships | Osaka, Osaka | 25th (h) | 100 m | 10.55 (wind: -0.6 m/s) |