A former cage fighter who died after he was pepper sprayed by police died as a result of misadventure and "cocaine induced excited delirium", an inquest jury has found.
Police failures may have also contributed to the death, the jury found.
Jacob Michael, 25, was arrested for alleged affray in Widnes, Cheshire, and taken by police van to a custody suite with his hands cuffed and his legs in restraints.
Footage taken from the police van and the custody office was shown to an inquest jury in which Mr Michael, who was known as Jake, can be heard repeatedly saying "please" and "sorry". His breathing appeared heavy and laboured, and he later died in his police cell while still in restraints.
The four-week inquest heard that Mr Michael was a cocaine user who would occasionally "binge" on the drug and he had been taking it on the weekend prior to his arrest.
Mr Michael had also been warned by doctors about the adverse effects cocaine could have on his heart, the inquest heard.
An inquest jury of eight women and one man at Warrington Coroner's Court, sitting at Daresbury Park Hotel, reached its verdict of death by misadventure after more than two days of deliberations.
Reading their narrative verdict, Nicholas Rheinberg, the Coroner for Cheshire, said: "Partying and his heart's susceptibility to cocaine probably contributed to the death."
The "fear, flight and fight" response caused during the arrest "may have also contributed to the death", the jury found.
The jury also found that "ineffective" police training, procedural failures, failures to carry out a "timely assessment" and a lack of communication may have also contributed to the death.