Essendon needs to improve its work rate and team defence after conceding on average almost 60 inside 50s a game in the first four rounds, coach John Worsfold says.

He said on Wednesday coaches would not excuse defensive efforts that were below par.

"Defensively as a team we are miles short of where we want to be," Worsfold said.

Essendon has conceded at least 60 inside 50s in the past two games, and has an inside 50 differential of -44 for 2017.

Worsfold said the match committee was open to the idea of midfielder David Myers returning to the senior side for the Anzac Day clash against Collingwood, but it would be a big call given Myers was yet to play a game after missing 2016 and most of the 2015 season.

"The way he trained today you would say he should be playing in the seniors, but he has missed a lot of footy, obviously, and we have to take that into account when selecting the side," Worsfold said.

"Is it more risk playing at AFL level than VFL level? They are the sort of questions we will ponder?"

He said James Stewart and Aaron Francis were also in the mix having shown good form in the VFL.

Worsfold said his comments after Saturday's 65-point loss to Adelaide about players "hitting the wall" had been made in relation to a couple of individuals rather than the team.

He denied his comments were in relation to a deeper issue around fitness caused by 10 players returning to the game. 

"The squad is unbelievably healthy in terms of fitness."