Among my geezer riding buddies, going to a lower drop bar as we aged is more common than raising the bar. Me too. This as a result of beginning to experience back pain. Why? My guess is that a more horizontal back is subjected to lower compression loads and higher flex loads, which latter are helpful. That said, these geezers ride a lot, which probably makes a difference. Going to a larger frame might be helpful in that it'll stretch a person out a bit more. Might depend of whether or not one currently has a slammed and flat stem. I've always like plenty of stretch. Seems easier on my arms and hands.
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Results matter