Nothing wrong with the information in the article but it lacks what is a good RHR at different ages

I’m 60, RHR averages 55. While I’m sitting programming it’s usually 53–58. Sometimes while sitting on the couch watching tv it drops into the 40’s.

Cycling is great and I try to do it everyday. If not cycling, walk or hiking. The more you get in shape, the harder it is to increase heart rate. It takes me 10–15 minutes of cycling to get a heart rate over 80. In other words hard to get to cardio. Hiking my average heart rate is usually 106.

You need to speak to this.

Most importantly, it’s not just water. If you exercise, you’d better replace electrolytes or your heart rate and BP will increase.