An eight-week study in the United Kingdom found that teens who wore a Fitbit Charge wristband became bored with it after about four weeks, and overall said they felt less confident about exercising and were discouraged from doing it, researchers reported in the American Journal of Health Education. Researchers also said that interacting and making progress comparisons with peers, rather than just working on their own with the technology, were better motivators for most of the teens in the study.