A 29-year-old British man was jailed for seven years after travelling to Syria in a bid to join militant group Islamic State of Iraq and Syria (ISIS).

The Daily Mail reported that former security guard Mohammad Uddin, who called himself "Supaman", had pleaded guilty to a charge of preparing acts of terrorism at Woolwich Crown Court on Tuesday (Feb 9).

Uddin, who lives in the town of Barking in east London, entered Syria via the Turkish border on Nov 4. He had boasted of the ease at which he crossed the border and claimed he was planning to fight for ISIS.

But he quickly grew weary of life in the war-torn region and was frustrated by his attempts to earn a ticket into Raqqa, widely known as ISIS' stronghold, as there was "high demand and not enough places".

In text messages to friends, Uddin also complained about the weather, a lack of hot water to shower with, stinky shared toilets, bland food and boredom from "doing absolutely jack (nothing)".

Having had enough, he tried to return to Turkey on Dec 12 but was detained by authorities near the Syrian border as he did not have a passport with him.

Upon his arrival at Gatwick Airport in Britain on Dec 22, counter terrorism officers again detained him. Extremist materials were also found in his possession.

The police learnt about Uddin when they raided his friend's home in Bedford, according to the Daily Mail. He had been in contact with Uddin and was preparing to travel to Syria to join him.

During his trial, the prosecution had noted that while Uddin had chosen to return to Britain, some of his messages to friends seemed to indicate that he intended to go back to Syria.