system
Given the following post, respond as if you're commenting on Reddit:
human
[Archer] How are Pam's family such unbelievably hard-ass fighters?

Even Pam's sister is a beast.  I pretty certain Pam could beat the crap out of Sterling if she got fired up.  What gives?
gpt
The Poovey Farm raises Holstein cattle, which at birth typically weigh up to 45kg and when fully matured up to 580kg. They're also about as tall as the average American female, around 150cm (about 60 inches, or five feet tall).

She and her sister would've grown up man-handling calves to feed them, and hauling equipment regularly to help the family out. Given their family's predilection for "robust" physiques we can presume they are likely from mixed Norwegian or German stock. Having larger bone density, larger frames, and the opportunity to develop significant muscle mass and tendon strength throughout their developmental period enabled Pam and her sister to learn the limits of their bodies' strengths as well as how and when the employ brute force to achieve what they wanted. 

Pam, especially, learned this on an unconscious level as she was teased regularly by her sister. From this dynamic, we can assume that Edie is (or was) the dominant sibling and that a consequence of Pam's difficult family life - hardships of a farm, zero tolerance for emotional weaknesses, and a highly-developed mental and physical tolerance for pain - which helps explain why she chose to enter a career that attempts to settle conflicts and bring people together.

However, her unconscious mind yearned to break free of the bonds of civilized society; to assert itself physically, now, in the only way Pam knew: brute strength. Pam began to fight as child, mostly with her sister, but as she grew older she found the cows could take a punch or two as well. So could the boys in the next town. And the men at the biker bar. She began to seek it out, the violence, to boost her confidence and give her the control, the dominance, and the recognition she so desperately wanted from her sister, and her family.

Fast forward, years later, Pam has been a regular member of various underground fighting rings. Always under a different name, she dips her wick in many styles, many arenas, many rules, all for the same outcome: to win. 

In her mind, though, she was always fighting Edie. Maybe a few stubborn cows, but mostly Edie.

Edit: Couple of words.