On the first 5 mile run watching my heart rate live, I could tell that up to 150 bpm was low work, but as soon as I got to 160 bpm this was the strongest and steady that I could go and not feel worn. So I am gauging 155 -160 bpm as the range I want to be in. Strong and steady but not over exerting my self. The Timex watch and chest band are sturdy construction and it has a cool indiglo light. For the basic runner this heart rate monitor would be too much, but someone looking to train better and get faster this is the right tool and the fair price.















