Nairobi, April 24 -- You check your smartwatch after a run. Your fitness score has dropped. You've hardly burned any calories. Your recovery score is really low. It's telling you to take the next 72 hours off exercise.

The worst bit? The whole run felt amazing. So, why's your watch telling you the opposite?

Ultimately, it's because smartwatches and other fitness trackers aren't always accurate.

Smartwatches can shape how you exercise

Using wearable fitness technology, such as smartwatches, has been one of the top fitness trends for close to a decade. Millions of people around the world use them daily.

These devices shape how people think about health and exercise. For example, they provide data about how many calories you've burnt, h...