I can't recall what specifically helped my forearm issues, too long ago...

But chiro did some myofascial release stuff ( Nimmo?), low level laser, IF stim, ultrasound all across my upper back , shoulders & neck, oh and the upper chest near the collarbones.

Plus my home self care stuff of tennis ball TrP work, posture, Sharon Butler stretches, far infrared heating pad & EMS(elec muscle stim)
vitamins & supplements - good multi , Cal/mag, MSM, Vit c, grape seed extract
water
Epsom salt baths