The Irishman is yet to start a first team league game this season and was loaned out to Brighton & Hove Albion but has the Coventry City door still open to him.
Said Coleman to the CT: "Kevin can run all day but it is a change of pace and strength that he struggles with. He can run all days towards the opposition goal but he finds it hard running back to his own goal.
"I was having a joke with him about it the other day but he needs to get stronger. He needs to be more explosive and get stronger.
"In terms of football ability, if we were playing on a half a pitch he would get 100 caps for Ireland because his footballing ability is lovely. But in our league which is hard and physical, you have got to run backwards as quick as you run forwards and you have got to be strong and have got a duty and job to do when you haven't got the ball.
"So Kevin needs to get stronger, be more explosive and more supple because he is quite stiff but his natural fitness is alright.
"His bother is a very gifted footballer and Kevin is a good footballer too - a natural footballer but he needs to improve on the things I have talked about. Certainly, as a natural football he has something to offer here."