The claims come as Donald lays bare the reckless spending that saw the club in a perilous position before his takeover in the summer of 2018.
Donald discusses the financial mismanagement of the previous regime during an episode of season two of the Netflix docu-series ‘Sunderland ‘Til I Die’ - which starts streaming today [April 1].
And among the more eye-catching of the expenditure he revealed was the cryotherapy chamber, which he claims to have been told was only used by Bain to aid his bad back - with first-team players not using the facility, which was designed to aid their recovery.
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Donald explained: “The club invested whatever it was, £100,000 plus on a cryo chamber for recovery.
“So I speak to the head of medical - ‘do you use it?’ ‘No.’
“‘Who uses it?’ Martin Bain goes in there for his back occasionally, was the answer that came back.
“[I asked] what players use it? ‘Oh, no-one uses it.’”
“There are hundreds and hundreds of examples of just spending money without asking a single question as to why they are spending it.”
During this discussion, which is held with fellow director Neil Fox, Donald goes on to explain how he has cut more money from the club’s budget - which included reducing the amounts spent on away travel and sports therapy.