Hi T Slow
My first question might be if you suspect you are over cooking the high intensity aspects of your training might you not begin to make sure you are doing a few of the following things.
Check your diet and make sure you are in good shape with regards to supplying enough protein, complex carbs and water. Pay special attention to foods that exist in nature. Try and reduce fake anything.
How is your water intake? Often overlooked and rarely thought of as important especially by non professional athletes and normal people
Address your sleep as number one thing to get enough of. How much sleep do you get? At what time of day? Is is solid sleep or is it interrupted? Do you need aids to go to sleep? Do you need stimulants to keep you awake to train or work?
You need to be doing a few things for your self ( massage, hydrotherapy are my favorites) to understand a before and after effect.
Others have spoken with regards to consistency of how you take your HR .Begin with what you aready have and the information you collect will encourage you to make the changes you need.
Do you want to be a massage therapist? or just learn how to give massages? Or receive massages?
Contact Grace Chan and use the site’s name as she was a contact of Charlie’s. Sutherland and Chan Massage therapy and she may be able to assist you.