As we get closer and closer to (fingers crossed) witnessing Olympic glory in Rio, Team GB's athletes are busy getting ready.
One of those is sprint cyclist Becky James. She uses her Fitbit blaze to track her all-day and resting heart rate - oh, and to identify general trends in her fitness. That way, she can even tell when she's coming down with something.
Here's exactly how she uses her wearable device... (be prepared for serious fitness inspo).
Good luck in Rio, Becky!