Anna, 30, captioned a photo of a fitness calculator, "Several of our friends made New Year's resolutions for fitness, started some kind of diet and decided to try to make some changes in the new year!"
The mother of Josh's five kids admitted, "I used the 'busy mom' excuse. While I made a noble goal of reading through my Bible this year, I thought I would skip the fitness goals. ? However, seeing the progress of my family & friends has inspired me to join in making a physical change for 2019!"
Then Anna told fans, "So... for the month of February I'm challenging myself to walk 50 miles. 2 or 3 miles a day will reach the goal with a few extra days to rest. ( Yes, I know you marathon runners can do this in like 2 days ??)."
Anna noted that her reason for sharing it on Instagram was "1. The accountability will motivate me to keep going and not to quit! 2. I want to invite y'all to join with me!!! Just use #February50 so we can keep up with each other!
The hash tag was for a support group of people who are also walking 50 miles over the month of February.
But Anna's new program might not do enough for her.
As Radar readers know, she sparked pregnancy rumors last year after being photographed wearing a large dress that looked like it was for maternity.
However, Josh's wife explained to fans at the time that she was just "overdue for a diet."
This week, in a shocking Instagram post, a fan asked Anna if she is planning on having more babies in the future.
"We would be thrilled if God blesses us with more children!" Anna responded.
She also said she's "not yet" pregnant again.
The 19 Kids and Counting wife's marriage to Josh, 30, was rocked after his past molestation scandal was revealed in 2015, followed by news of his infidelity.
In Touch revealed that Josh was accused of molesting his younger sisters between 2002 and 2003. At the time, Duggar and the girls were all minors.
Josh's alleged sex crimes included "fondling" his four sisters' (and a family friend's) breasts and private areas, according to a shocking police report.
Josh hasn't appeared on the Duggar family's TLC reality show Counting On following the scandal.
Despite the disgrace, Josh recently caused rumors that he's planning on making a comeback to TV after he was spotted bonding with his distant siblings.
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