Evo-Stik League club Colwyn Bay enlist help of boxing champ
Bay, who are in the Evo-Stik Northern Premier League relegation zone, were put through their paces by Mathews at his Liverpool gym.
Seagulls manager Kevin Lynch is a good friend of Mathews.
"He's got a great personality about him to rally the troops and work the lads really hard," Lynch said.
"The lads needed picking up and I can't thank Derry enough. It's been inspiring."
Mathews, 32, faces WBO lightweight champion Terry Flanagan on 13 February in Liverpool.
Lynch took over in October 2015 from Ashley Hoskin, who had only been in charge for five months following relegation from the National League North at the end of the 2014-15 season.
The former Southport player inherited a side that was 20th in the table and had to wait until 2 January for his first league win in charge, a 2-1 victory at Workington.
"I'm not going to lie, it's been tough," Lynch added.
"When I first came in I felt the fitness levels weren't good and what you need is a bit of a variety in training so the lads can respond.
"I got in touch with Derry and he kindly took the training for us. It's nice to take players out of their comfort zone and putting new methods in towards training.
"It's good for team building but very tough and I think it's what we need to get us to where we need to be.
"If we're going to have a fighting chance of getting out of where we are then we definitely need to pull on all the resources and skills of other people to help us."
Mathews won the interim WBA lightweight title with a unanimous points decision over Tony Luis in April 2015.
The former British and Commonwealth lightweight champion is currently in Spain preparing for the fight against Flanagan but took time out to tweet his congratulations following Bay's win at Workington.
Lynch hopes to attend Mathews' fight against unbeaten Flanagan at Liverpool's Echo Arena on 13 February after Bay's game at Stourbridge earlier that day.
"He's training really hard for his upcoming fight against Flanagan," Lynch said.
"For what he's doing for us the least we can do is give him our support and we wish him all the best."