Vladimir Putin's unusual walk is the result of KGB or weapons training, not because of Parkinson's or a stroke, scientists have suggested.

Analysis of Putin and five other top Russian officials shows they all have a similar walking style – something scientists have dubbed a 'gunslinger's gait' because they have reduced right-sided arm swing.

The research, carried out by an international team of scientists, was published in the BMJ's Christmas edition, which covers more quirky and fun topics. Researchers were looking specifically at Putin and his walk, which has previously been debated by experts. Theories have ranged from Erb's palsy, intrauterine stroke and a sign of Parkinson's disease.

In the article, the team of movement disorder experts examined the walks of Putin, Prime Minister Dmitry Medvedev, defence minister Anatoly Serdyukov, chief of the presidential administration Sergei Ivanov and commander of the Western Military District Anatoly Sidorov. All five were found to have reduced right-sided arm swing.

Because the chance of them all having early phase Parkinson's is pretty low, the team looked for other possible explanations for this gunslingers gait. "None of the five Russian officials displayed any other evident motor signs suggestive of early Parkinsonism," they wrote. "For example, Putin has otherwise excellent motor skills: his handwriting is fast, there is no micrographia or tremor, right hand movements are fast, he is a judo black belt and an excellent swimmer, and has no difficulty lifting weights."

In their research, the scientists came across an old KGB training manual, which detailed how operatives should move when out in the field. "When moving, it is absolutely necessary to keep your weapon against the chest or in the right hand," it said. "Moving forward should be done with one side, usually the left, turned somewhat in the direction of movement."

In their research, they found that four of the five officials were linked to the KGB or the military, with the only exception being Medvedev. He, they say, may display the gunslinger's gait in order to "imitate the boss": "Substantial evidence suggests that Medvedev is being coached to sound, look, and, importantly, walk like the president," they said.

As a result, the scientists theorise that the walk could be the result of military or intelligence training, rather than being pathological. "We feel that there is another – and perhaps more plausible – explanation [for the gait], namely a behavioural adaptation resulting from military or intelligence training," they said.

"A supportive argument is the fact that trainees undergoing KGB training are taught to keep their right hand close to the chest even while walking, allowing them to quickly draw a gun when faced with a foe. It is conceivable that other forms of weaponry training are associated with a similar behavioural gait adaptation."