Sir Bernard Hogan-Howe, the Commissioner of the Metropolitan Police, has warned fat officers there is no place for them on the force.
Britain’s most senior policeman said when the public and other officers called for help they did not expect someone to come “waddling down the road” and “out of breath”.
He said he welcomed the compulsory annual fitness tests that were introduced last year but admitted that they were not strict enough and were failing to weed out overweight officers.
The fitness assessments were brought in following recommendations by Sir Tom Winsor, the chief inspector of constabulary.
All officers must now complete a shuttle run or bleep test, running between two points 15 meters apart as the gap between the bleeps gets shorter.
Despite criticism that the tests were far too easy, figures published obtained earlier this year showed that hundreds of Met officers had failed to make the grade.
Sir Bernard, 57, who is a keen footballer and horse rider, and who passed the test easily “without any preparation”, said he believed the standards needed to be higher.
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In an interview with the Radio Times, he said: “For me, the standard is too low: I think it should be higher. It’s relatively easy to pass.”
Sir Bernard, who joined the police in 1979 in his native South Yorkshire, said if officers could not reach the standards expected of them then they would be kicked out of the force.
He said those who failed would be given time to get fit and try to pass again, but added: “If they don’t, then we haven’t got a job for them. I think you’ve got a duty to your colleagues.
“If they shout for help, they want fit people to come. They don’t want somebody waddling down the road who’s never going to arrive, and when they get there they’re out of breath.”
But Sir Bernard, who made his most recent arrest last year when he apprehended a man who had run off without paying a cab fare, said age was not a barrier to good policing.
He said he was full of admiration for “60-something officers” who were still on the front line, fighting strong athletic 18-year-olds, adding: “that takes guts”.
With increasing cuts putting pressure on frontline policing and Bobbies on the beat, much of police work is being done using technology such as CCTV.
But Sir Bernard rejected suggestions that Britain was turning into a surveillance society, pointing out that often the police did not have the same ability to use technology as taxi companies, who are able to use mobile phone signal to locate a customer quickly.
He said: “They will know where your phone is and where the taxi is and then put you together. But when people ring the police, we haven’t got a clue where that phone is. You may have been stabbed and expect us to come and help.”
He said the police could not use location data in “real time”, adding: “We have to make an emergency application, there’s a process to go through.”