I’m quoting from a Sally Jenkins article in the Atlantic.
The first mention of an athletic contest in colonial America comes from the separatist Pilgrim leader William Bradford who journal notes that in 1621 … he disciplined a group of young men for evading work on Christmas to instead engage in games such as “pitching the bar,” a contest to see who could throw a heavy rod the farthest.
George Washington won a contest of bar pitching at Valley Forge.
There could be some sort of correlation. AIUI, a lot of Arabic words are formed based on consonant patterns: the ‘rg’ pattern here would seem to suggest that – except, the original consonant from what is rendered a “reg” is q, which is pronounced differently than g or k (kind of like an enunciated glottal stop).
And, of course, “erg” is a dune, while “reg” is a hardpan field of gravel, so they are different things.
What the OED says about the relationship between the two words is not entirely clear to me.
For “erg”, it gives the etymology
French (E. Fromentin Un été dans le Sahara (1857)) < N. African Arabic‘irj, of Berber origin.
For “reg”, it says
< a colloquial (Maghribi) pronunciation (see below) of Arabicriqq, variant of ruqq, raqq, in same sense. Compare Frenchreg (1923; < Arabic). Compare earlier erg.
In colloquial Maghribi Arabic, the three short vowels i, u, and a of literary Arabic merged into schwa. The pronunciation of the literary Arabic voiceless uvular plosive /q/ as /ɡ/ is characteristic of Bedouin dialects.
So it might be saying that “erg” and “reg” derive from the same Arabic word via different dialects, but I’m not entirely sure. The “compare” note in “reg” suggests there is some relationship.