Do you leave your wallet in a back pocket? That is a guaranteed backache for me.
As far as lumbar, I set the seat so my back is straight.
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Amen.
A bulky wallet in a rear pocket has been known to cause nagging back problems for a lot of drivers over longer hauls, or if driving a lot over shorter hauls but daily. Throws your whole balance off.
Also noticed by many is that their back aches after a long drive because they don't usually do long drives nor sit in one position for that many hours.
I've driven so many hundreds of thousands of miles over the years on both interstate and back country roads that I've learned to take breaks, get out and walk a bit, change up my position, do stretches at rest areas, go walk around small towns, etc. Makes a huge difference in how I feel at the end of the day on long trips.
No lumbar support, no heating pads, just paying attention to my posture, how my body is being used, and how it feels.
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