Amongst last season's squad back today are the new signings Iain Hume, Hugo Roberto Colace, Mounir El Haimour and Darren Moore.
Kidd says the players can expect a tough pre-season regime to ensure they hit the ground running at QPR on 9th August.
He told www.barnsleyfc.co.uk:
"It has been a very tough day for the lads. I do not think they will have had a tougher first day of pre-season at any club. We have worked this morning and afternoon and started with some endurance and aerobic work. We are following the same plan as we did last season and it will be tough for them.
To read the full report from Kidd click here
Meanwhile new recruit Darren Moore has claimed that he has made his move to Oakwell ten years too late!
He told Barnsley World TV:
"When Barnsley were promoted to the Premier League I remember that there was a lot of speculation that I could be joining them from Doncaster. It was a big thing at the time but it just never came about because the clubs could not agree a fee. It is great to see that the club moved on from that time and used it well by building the great facilities Oakwell has today".