Back pain? Amazon's tiny fitness tracker might be able to help

Amazon has launched a new tool for its Halo fitness tracker that helps you develop 'functional strength', making it easier to carry out everyday tasks that involve lifting, pushing, carrying, bending, and reaching.

Movement Health, which was first announced earlier this month, is rolling out now through the Amazon Halo app. The tool will walk you through a set of five movements to test your flexibility and balance, while recording yourself using your phone's camera.

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While you perform each exercise, the app will analyze your movement and identify limitations in your posture, stability, and range of movement.

Once that's done, you'll be given an overall movement score out of 100, plus details about your general mobility, and a breakdown of information about your core, hips, lower body and shoulders.

A low score doesn't mean that you're unhealthy; just that you have some limitations that are reducing your movement, and can be worked on.

The app will then give you a list of 'corrective' exercises to help address any areas that could use a little help, with videos to guide you through the process. Each set of exercises takes around 5-10 minutes, and Amazon recommends doing them at least three times a week. Every couple of weeks, check in with the Halo app to monitor your progress.

The Halo effect

The Amazon Halo is an unusual fitness tracker. It measures your daily steps and nightly sleep in the same way as a Fitbit, but it has no screen so you can only check your stats through the app – and it does a lot more besides.

The Halo is pretty simple in terms of hardware, but it's able to call on of its features rely on your smartphone's hardware and Amazon's cloud computing clout. One of its most interesting (and potentially unsettling) tools is Body, which asks you to take photos of yourself in snug clothing, then uses them to build a three-dimensional model and estimate your body fat percentage.

You can then track how your body fat changes over time, as a result of lifestyle changes - the idea being that body fat is a more useful metric than weight alone, which can be affected by muscle and water mass.

Amazon Halo body scan with 3D render (Image credit: Amazon)

These can also be measured by a smart scale (such as the Eufy Smart Scale C1 or Withings Body+) but Amazon's app helps you visualize changes, and has compared favorably with industry-standard DEXA scans for measuring body composition (albeit in a small survey).

The Halo can also use input from its internal microphone to analyze your tone of voice and choice of words, and assess your emotions. Your voice is assessed according to energy and positivity, so you can see later whether you sounded tired and miserable, or warm and appreciative.

This could be seen as somewhat creepy, but it's certainly novel too, and it'll be interesting to see what other new features Amazon adds to the Halo app over the coming months.