All 24 players took part in the first sessions and listened to Adkins spell out his plans for the season.
"It's important as we start off this way to see where the players are, everybody is looking fit and hungry," he told the Iron's official website.
"We had a good meeting about the fresh challenges ahead for this season and we all have a smile on our face. The lads look fresh after their summer break and are really looking forward to pre-season.
"The two new lads have settled in very well. Bobby Grant is very bubbly and Chris Dagnall has joined us too. They've settled into the group we've got very quickly, which is very encouraging to see."
The centre-back Kenny Milne was part of the squad on Wednesday despite not yet formally agreeing a new contract to stay at Glanford Park.