In the last few years one can clearly notice a trend to self-monitoring. Hart rate monitor watches are available for a few bucks, Nike's fuel band and the fitbit are a big success, apps for monitoring sport activities (e.g. runkeeper or runtastic) are available. Apple presented its health kit and Google's response Google Fit has been presented as well. I've been at the band waggon as well, I really liked tracking myself. I even tried out sleep monitoring, as offered by several mobile apps.
But honestly it just led to geeking about the measured stats. It didn't lead to more sports activities, the opposite was the fact: due to some obscure defiance-ish reasons I stopped doing sports. While originally sports was a good possibility to have some alone-time and clear my mind it mutated to some pressure-induced compulsion not only to do sports but also to be successful with it.
Thus I decided to stop monitoring myself completely (well, I do measure blood pressure regularly for health reasons: high blood pressure is a good indicator for a lot of diseases). And as a consequence of this, I now can go out with the dog for a long, fast walk or do some jogging or biking and get my mind clear again. This is really relieving.