Antonio Conte admits he is worried about his heart as Chelsea's form fluctuates this season.
A demonstrative figure on the sidelines, Conte's heart has been tested early into life at Stamford Bridge, with the highest of highs being last week's remarkable 4-0 rout of Premier League rivals Manchester United.
Chelsea, though, have already lost to Liverpool and Arsenal, while stuttering to a 2-2 draw against Swansea City and losing to West Ham in the EFL Cup fourth round midweek, frustrating head coach Conte, who joked about using a heart monitor.
"I am worried about this [heart]," Conte said.
"For this season I try to do my own training sessions to maintain good physical form.
"I know I risk a bit, but I might consider putting a GPS system on myself to monitor my heart-rate during a game."
The 47-year-old Italian added: "Whenever I have time, I run. For 30, 40 minutes. I change the routes.
"When we finish training, if I'm not tired, I have my period of fitness. We have four pitches here and I run around them. Sometimes I try to involve my staff."
"At the start of my career, I would eat very well and I felt the benefit of it. So when I became a coach, I wanted to have the same idea," he continued.
"You don't ban anything. You just aim for the right balance between protein, carbohydrates and fat. It's important in preventing injuries and in recovery. You are fresh mentally, too. I have tried it on myself."
Chelsea are fourth in the Premier League as they prepare for Sunday's trip to Southampton.