I love love love to run! If you haven't run in a while, it may just be the normal "getting back into it" soreness. Don't overdo it, just take it slow, even if you can only run/walk a mile to start, just take it easy and make sure you stretch nicely afterwards, maybe use a tennis ball to roll the lactic acid out of your sore calves.

Calf soreness is perfectly natural when switching to a forefoot strike. As long as you run with some regularity, it shouldn't be a problem for much longer.

Think about it. Have you ever heard of folks complaining about how women's legs and feet get all wonky from constantly wearing high heels? It's because raised heels shorten the Achilles and it actually atrophies because it is prohibited from a full range of motion. All the shoes we wear today are lifted in the heel, thereby atrophying everyone's Achilles (and other related muscles and ligaments, etc.) to varying degrees.

The Achilles tendon is not a muscle and can't be stretched out quickly. This will take time to undo all the years of abuse. Trust me, I know. I've been at the forefoot strike and barefoot running now for a little over a year, and my calves still occasionally get sore. If you're a runner who's used to high mileage, please promise me that you'll take it easy with the forefoot stuff for a few months. Otherwise, you might be one of those folks who gets injured right outta the gates and declare that forefoot striking "doesn't work for me". When your muscles are "sore", this means your joints are at risk because they don't have the normal support they require to hold them together properly. So don't overdo the stretching when you're sore! This may feel good in the short term, but it's actually counterproductive. Let it heal before going out hard again.

It will also help to go barefoot as much as possible elsewhere, at home, in the garden, etc. I've also begun switching out almost all of my shoes to ones with zero or little drop.

Welcome to the wonderful world of forefoot striking! Be sure and try some actual barefooting to refine your form. Can't fake it when you're barefoot.

I've been playing around with a forefoot strike on my runs, and I can definitely feel it in my calves afterwards. You're not alone, though I can't say if this is normal or to be expected.

Ease back into it. I run marathons.. and I just started to transitioning into minimal running shoes for my longer runs. Dont over do it. You will feel it more in your calves.

Welcome back to running :) Ensure you are running on your mid-forefoot and not on your toes. That would definitely cause calf pain. Everything from your knee down should be relaxed when running, including your feet. If you video yourself running it will give you pointers. Read up on POSE running technique and if possible get some coaching.