Town have been back at their Sundorne Castle training HQ for a little over two weeks now, where they have been put through their paces by the manager and his team, who are expecting top fitness levels.
The Shrews squad were expected to complete strict individual exercise across five of the seven weeks they had off for the summer. Cotterill revealed this week players were fined £500 for each missed session, which would be digitally logged to fitness staff for proof of completion.
It is understood players have found the return to training demanding but morale among the troops has been high, as the boss continues to build his squad for the new term.
Cotterill, whose side are without a friendly this weekend after the trip to Tamworth was cancelled 'due to unforeseen circumstances', said: "Do I think they've responded to me being back? I don't know what they were like while I was away!
"Like they say 'when the cat's away the mice will play', but I didn't see any of that in them last year in terms of their professionalism, attitude, they were incredible last year.
"You don't do that for somebody you don't have respect for or like, while they aren't here.
"So I wouldn't expect anything different with me being here.
"But if you're asking me if they've given absolutely everything they've got on the training ground so far, yes they have - and more.
"If they satisfy me with what they've done, I'd imagine they'd satisfy themselves."
Cotterill knows his road to recovery after severe Covid-19 is a long one, but is determined to return fitter and stronger than before his illness.
He admits, for the moment however, he has to be 'sharper' with people – but not out of frustration. The boss added: "It's like getting a slow motor going early in mornings, then I feel incredibly tired at night.
"But in between - does it feel natural getting back out on the training ground? Yes, but my talking has to be short, sharp, to the point.
"I've said to people I'm speaking to - I have my watch telling me what to do and to take more breaths.
"Getting on to the training ground is no different but I have to be short, sharp, precise, and explain that I'm not agitated or angry, it's just I can't elongate long sentences.
"I'm not actually (being) sharp, it just stays in my airways a little bit."