Ann Hooper, of Bonners Glen, Axminster received £33,000 in disability payments before the scam was exposed. Jurors at Exeter Crown Court were told the fraud went on for three years.
Ms claimed both for herself, and for her two adult sons.
She claimed disability left her “too disabled to move”.
She told nurses she couldn’t walk more than 20 meters without support from a stick.
However, Ms Hooper was filmed at a supermarket in Axminster, Devon, walking without any support.
The footage was taken by the Department for Work and Pensions, in a surveillance operation.
Ms Hooper claimed her two sons were unable to climb out of their wheelchairs.
The court heard one had been spotted walking for a mile without a stick, whilst the second went to Canada for two adventure holidays.
Video played to jurors showed one of the sons weightlifting at a gym.
Footage was also played of the second brother, who spent an hour walking around a showground with only a mild limp.
Ms Hooper was convicted on three counts of benefit fraud.
Judge Timothy Rose, who presided over the case, said she made “demonstrably untrue” claims during the trial.
The defendant had claimed her sons were testing their strength when filmed, and insisted the disability claims were genuine.
Judge Rose commented: “You proceeded to lie throughout the trial as if you were ignoring the reality of the situation.
“You lied extravagantly to the jury. It was ridiculous.”
Defending Ms Hooper Barry White said all three family members have genuine disabilities, and are entitled to benefits, even if not to those they had been claiming.