Who says a Duggar girl cannot be as tough as nails?

17-year-old Joy-Anna Duggar proved that despite her family's strictly conservative upbringing, she can still beat a majority of grown up men by lifting weights at a whopping 145 pounds, which she exhibited during one of the gym sessions she spent with the family. 

Big sister Jessa managed to capture her younger sister carrying a set of heavy weights during their gym time, and posted it on Instagram with the caption, "Joy was tearin' it up in the workout room today! She beat her previous record by parallel squatting 145 lbs!! Keep it up, little sis!" 

But since she is born a Duggar, Joy is expected to wear something unusually conversative during gym time — a long skirt, a cardigan, as well as matching tight pants complete her workout clothes. Her mother Michelle explained why the kind of clothes her children wear have to be restricted.

She said: "We felt like we needed to be covered from our neck to below our knees mainly because God talks about the thigh being uncovered, and how that's nakedness and shame. And so in our dress — whether we're doing activities that require us to climb, ride a horse, bike, swim, whatever — we just want to keep the thighs and torso covered; we don't want to play peekaboo so that there's a visual element that might defraud someone." 

Meanwhile, her new son-in-law discussed how the family spend gym time, saying, "We do a lot of weight lifting and cardio together, trying to stay fit. Some of the other kids, like Joy and Jason, sometimes join in. We have a little workout club going." 

Joy-Anna and Jessa belong to the large and popular Duggar family that stars in the hit reality show titled "19 Kids and Counting," which airs Mondays on TLC.