Zykov left his native village to work as a gold miner and was drafted into the Imperial Russian Army in 1911, becoming a non-commissioned officer. Serving with a reserve unit during World War I, he participated in the October Revolution in Ashgabat and joined the Red Army during the Russian Civil War. He fought in North Russia and was decorated for his actions, ending the war as an assistant regimental commander. Holding command positions in reserve units from the late 1920s, Zykov rose to division command in the late 1930s. He commanded the 121st Rifle Division from the beginning of Operation Barbarossa, leading it in the Battles of Białystok–Minsk, Smolensk, Moscow, and Voronezh. After a stint as 60th Army deputy commander in late 1942, Zykov commanded the 18th Rifle Corps in the Soviet advance into Ukraine after the Battle of Stalingrad in early 1943, before returning to his old position as 60th Army deputy commander. He held this position until late 1944, when he was transferred to a noncombat post as military district deputy commander due to health issues. Zykov retired shortly after the end of the war.