He was seen putting the players through a tough session before making them run 42 lengths of the pitch in 30 degree heat.
The training saw several players fall to the floor exhausted, while it was reported Harry Kane had been sick.
But rather than hate the man putting them through their paces, Doherty revealed the Italian is well-liked.
And sessions like the ones witnessed aren't unusual.
"Yeah, [they're] pretty normal. Even the week before in London was along those lines so I don't know if there will be any teams fitter than us. It's not like anything I've done before. This is hard. It's the hardest pre-season I've had," he said.
"You get a great satisfaction once the session is over. Your mind has been tortured in the middle of it but when it's done you feel proud and you got to bed at night time thinking 'yeah, I've worked hard today'."
He added: "During it you're just thinking don't quit. Even if you crawl over the line or you have to jog or walk towards the end. It's that determination the manager has kind of instilled in us to keep going and never quit."
"It's all love for Gian Piero actually. It's funny because we were having this conversation. Normally when you have a fitness coach like that who is running you ragged you start to not like him but that's not the case. We all absolutely love him," he said.
"We've got so much respect for him that we do whatever he tells us to."
Ventrone has previously utilised a number more humiliating methods to get the best out of his charges but Doherty reveaed the fitness coach must have mellowed over time.
"There's nothing like that [here]. I think he's actually calmed down a lot in the last few years," he said.
"We're getting the sentimental side of him! Seriously though, it's incredibly tough and they know what they're doing so we trust them."