Amazon announces new wireless earbuds, Echo Buds, at an event in Seattle on Sept. 25, 2019. CNBC | Todd Haselton

A hidden feature inside the Alexa software shows Amazon has at least considered enabling the Echo Buds earbuds to track workouts. This backs up CNBC's earlier reporting that Amazon was planning to add fitness tracking features to the Echo Buds as part of an update code-named "Puget." Amazon launched its headphones in October but has not yet talked about any sort of ability to track health or fitness. The feature, which CNBC discovered on a test unit of Echo Buds paired with Amazon's Alexa app, appears to be in a testing phase, and there's no guarantee that Amazon will ever ship the feature. An Amazon spokesperson declined to comment on the discovery. But if Amazon activates the feature on the Echo Buds, it would mark Amazon's first entrance into the fitness monitoring space, bringing into more direct competition with the Apple Watch and Fitbit, which Google announced plans to acquire last week. Amazon has been hiring healthcare experts and has a team within Alexa that's entirely focused on health and wellness.

What we found

Amazon sent us a version of the Echo Buds to review a few weeks ago. While writing a review of the Amazon Fire HD 10 tablet on Tuesday, I paired the review unit Echo Buds to listen to some music. As I was moving through the Alexa app on the tablet, which is how you manage the Echo Buds connected to a device, I saw something I didn't see when I first reviewed the Echo Buds a couple of weeks ago. Inside the Alexa app, under where you would normally manage the equalizer settings for the Echo Buds, was a whole new "Fitness" section.

You can't yet track workouts, but the feature is appearing in the Alexa app if you have Echo Buds. Todd Haselton | CNBC

The section included the option to track a workout, a fitness profile that included only a space for my height, and a Workouts heading.

You can only enter in your height right now. Todd Haselton | CNBC

Under the Workouts heading, it suggested I could start tracking a workout by speaking "Alexa, start a workout." I said this and it said "OK, starting your workout." I walked around the office with the Echo Buds in my ears, and it appeared to have tracked my movement, telling me, "You've worked out for 1 minute and 37 seconds. You've logged 0.04 miles with an average pace of 44 minutes and 13 seconds per mile. You took 114 steps." Here's a summary of my activity that appeared after I tested the option several times:

Todd Haselton | CNBC