Guys I’m guessing I’m a heel striker and maybe gotten worse with age. Always hole in left heel on the bottom after trail or road run. I tried better thicker socks but same result. Tried a more cushioned heel and still the hole.
Do i just have to accept it and get new socks constantly? Or just work on more of a mod foot or forefoot strike?
Edit; mid foot strike
Get shoes that fit. You probably have different size or shaped feet. Quit buying shoes mail order and beat it to a running specialty store with experts that can fit you.
Your foot is sliding forward inside the shoe with each foot strike. This rubbing is wearing out your socks on the bottom of the heel. The cause is you are overstriding and landing on your heel while the foot is still moving forward. One fix would be to change your running form, but unless you're getting injured from overstriding, that's a pretty radical step to take.
A simpler solution would be to switch to butterfly lacing to hold the heel snug in the shoe. There are several techniques for butterfly lacing on YouTube. Try them all until you find one that works for you.
If that doesn't work, switch to a shoe with a rocker sole, like the Hoka. These rocker heels slightly shift the impact point forward, which might be enough to stop your foot from sliding in the shoe.
I've used my own variation of butterfly lacing for years. You should be able to feel the difference. Try lacing one shoe butterfly style and leaving the other as is. Your heel should feel more secure and snug in the shoe with the butterfly lacing.