

I don’t trust the Garmin heart rate monitor, at least on wristwatches. I’ve used cardio equipment at the gym with HR feedback. I know my HR is elevated, the cardio equipment reads 140 bpm which feels about right to me, and yet my Garmin says 90 bpm. One of these things is not like the others.
I’ve never seen these bands so I can’t comment on them. But if what you’re describing is shin splints (sore and sensitive to the touch on the front of the lower leg) then calf compression sleeves can help to prevent it. Also, look up some videos on ‘heel striking’ and try to make sure you aren’t doing that as it can cause knee injury. But first, take a day or two off to recover. Progress will be slow at first so you gotta play the long game when it comes to running.