There has also been a focus on improving training and medical facilities in an attempt to improve the club's record with injuries.
Several new appointments have been made to the medical staff and the club is in the final stages of purchasing land for a new training complex in Romford, Essex.
"We are trying to make the best of the know-how and expertise that we have at the club," the source said.
"The aim is to have first-class medical and training facilities, to rival those at the biggest European clubs.
"At best, we managed to field six or seven of our first team at any one time last season. Just imagine how well we could have done had the likes of Kieron Dyer, Craig Bellamy, Julien Faubert and Dean Ashton available all season.
"We have to try to keep these players fit. We also have a lot of good young players coming through, such as Freddie Sears and James Tomkins.
"The optimum squad size is probably about 26 or 27 players. Our squad has become so big for a couple of reasons - the relegation battle we had in 2006/7 and the spate of injuries of 2007/8."
When Gudmundsson bought the Hammers in 2006, he laid out a five-year plan that, he hoped, would ultimately culminate in qualification for the Champions League.
West Ham finished 10th last season and the target for the coming season will be to challenge for a Uefa Cup spot.
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