Ex- offenders are being exposed to temperatures as low as -10C to keep them on the straight and narrow.
An organisation linked to the Scottish Prison Service is using cold water therapy to help rehabilitate former convicts.
Known as the Wim Hof technique, it involves plunging ex-prisoners in a freezing river for up to three minutes at a time to shock their systems and help them improve their will-power.
The therapy, named after a Dutch extreme athlete who invented it, teaches them to control their thoughts and breathing to be able to withstand the extreme cold.
In doing so, it helps them deal better with traumatic incidents from their past, including serious and violent abuse and addiction.
The programme is the brainchild of Natalie Logan MacLean, chief executive of Sustainable Interventions Supporting Change Outside (SISCO), a Glasgow -based organisation that supports the liberation of ex-prisoners.
It works in partnership with the Scottish Prison Service to help former criminals get back on their feet. Natalie, 33, told how, once a week, they take a group of 30 hiking at the Campsie Fells then they plunge into the River Carron.
She added: “Cold water therapy is one of several strategies we use to help them come to terms with who they are and what they’ve done.”