Love this app!

The signals for upper and lower range you set work well. This then enables me to train “slower” because Ive found a major problem (poor aerobic function), which I now have the challenge to correct. You’re not only going to be faster (at the same heart rate), but more fit (to race better) and healthier.

Excerpt From: Dr. Philip Maffetone. “The Big Book of Endurance Training"

Marian1030 about ithlete Train.Recover.Perform, v3.0