John Mwathiwa was 29 years old at the time of these Olympics, and was making his third consecutive, and final, Olympic appearance. On 4 August, he took part in the Marathon, a race that was held without rounds or heats. He finished in 2 hours, 24 minutes, 45 seconds, which put him in 65th place among 111 athletes who finished the race. The gold medal was won in 2 hours, 12 minutes and 36 seconds by Josia Thugwane of South Africa, the silver by South Korean runner Lee Bong-ju, and the bronze was won by Kenyan Erick Wainaina.