Mio Slice with PAI

Mio Slice with PAI
  • Editor Rating
  • Rated 4.5 stars
£119 to £119
  • 90%

  • Mio Slice with PAI
  • Reviewed by:
  • Published on:
  • Last modified: 23rd February 2017
  • Heart Rate Monitor functions
    Editor: 80%
  • Heart Rate Accuracy
    Editor: 97%
  • Activity Tracking features
    Editor: 95%
  • Fitness monitoring features
    Editor: 90%
  • Ease of Use
    Editor: 90%
  • Battery Life
    Editor: 90%

The Mio Slice is the world’s first activity tracker to feature PAI. Personal Activity Intelligence is a measure of heart rate intensity throughout the day. Mio realised that counting steps is not the best method of measuring personal activity throughout the day. The Mio Slice has been reviewed by Tristan Haskins

The Mio Slice - worlds first activity tracker with PAI

Release Date (UK) > Feb 2017

Product it replaced > new product – first with PAI

Suggested Retail Price (at time of release) > from £119

Who’s it For?

It took me a few days to fully appreciate the Mio Slice and PAI(¹). I have spent many hours testing fitness trackers with a daily step target, generally aiming for a 10,000 step daily target. The Mio Slice promotes a very different and innovative activity goal. The Slice use PAI. PAI stands for Personal Activity Intelligence. In summary, it’s a clever algorithm based on heart rate intensity and duration rather than just steps, measured continuously throughout the day.

NOTE > you must have a smartphone to setup and manage the Mio Slice. It is NOT possible to use it in a standalone state. Do not buy the Slice if you don’t own a smartphone (iOs or Android).

Aim for 100 PAI per week

The aim is to maintain a running weekly total of 100 PAI. In the two weeks I have been using the Mio Slice I have seen between 114 PAI, my lowest 7 day score, and 125 PAI, my highest. The Mio Slice is for those interested in effectively monitoring their daily activity /intensity, BEYOND step counting.

Quick Links – lowest prices

PLEASE use the links below to check for the lowest online prices of the Mio Slice Fitness Tracker

Thank you for your valued support … Tristan

Mio Slice available at Amazon

Why Move the Goalposts?

We’ve got very accustomed to measuring our daily activity by the number of steps we take. Working, as I do, for 8 hours per day from home, there are days when I may not even reach 4,000 steps. However, i like to think I am reasonably fit. I exercise every day if possible, but a lot of this time is spent on my bike, turbo trainer, elliptical trainer or doing HiiT training. None of these rack up the step counter … but they are all helping keep me fit. This is what Mio recognised with the Slice. PAI addresses this by monitoring daily heart rate instead.

10,000 Steps is 10,000 Steps … Right? Wrong

Here’s a couple of scenarios to show why STEP COUNTING alone may not be working for us …..

Scenario AMr Smith has a sedentary job and does very little, if any, specific exercise. Every day he slowly walks to work and in the evenings he walks his dog, also slowly. His Fitbit Charge 2 informs him every day that he has achieved his daily step target. Well done Mr Smith! However, he’s not even broken out in to a sweat. His heart rate hasn’t once elevated above 90 bpm (under 50% of his MaxHR). YES – he is achieving 10,000 steps per day. NO he is not going to make any significant improvements to his long term health & fitness. If he was wearing a Mio Slice his weekly PAI score would be less than 20 from a target 100

Scenario BMr Jones also has a sedentary job and does very little, if any, specific exercise. However, every day he strides to work occasionally jogging for 2 to 3 minutes. In the evenings he takes his dog for a power walk. He alternates between hard striding and light jogging. His Garmin Vivosmart HR informs him that he too has achieved his daily step target of 10,000 steps per day. If he was wearing a Mio Slice his weekly PAI score would be in the region of 70-100

Using the daily step method of activity tracking, Mr Smith and Mr Jones have very similar activity levels. They are both walking 10,000 steps per day. However, Mr Jones’s daily activities, often performed at a heart rate over 55% of Max HR, should result in significant improvements to his long term health & fitness. The Mio Slice would clearly identify the difference in the activity profile of Mr Jones & Mr Smith.

Update 20th Feb > Now I fully understand the concept behind PAI (Personal Activity Intelligence) I am totally convinced this is the future of fitness tracking. For anyone with Strava Premium you can look at PAI in a similar manner to “Suffer Score” … Just walking around all day without stressing your cardiovascular system will NOT register on the PAI score. You need to get the heart rate pumping for several minutes to register for some PAI. Last week I managed a PAI score of 134…. the aim is to achieve 100 each week. A 20 mile V HARD (heart rate zone 4 for 80% of time) bike ride on Sunday was rewarded with a PAI of 64 !!

Main Features

  • Mio Heart Rate Technology – the original innovators of WRIST BASED heart rate
  • All Day Heart Rate Tracking – the Slice records your heart rate 24/7
  • Personal Activity Intelligence – Aim for a PAI score of 100 points per day
  • Activity Tracking – tracks steps / distance / calories burned
  • Broadcast Heart Rate to other ANT+ devices, eg Garmin Edge
  • Water Resistant – Up to 30m / 100ft (fine for surface swimming)
  • Sleep Tracking – monitors the quality and duration of your sleep
  • Smartphone Notifications – receive smartphone alerts for calls, texts etc

Wrist based Heart Rate

The images below show the rear of the Mio Slice and it’s patented LED sensors. These sensors read the heart rate directly from your wrist 24/7. This is how the Slice can calculate a PAI score. Mio were the innovators of this strapless heart rate monitoring and can be thanked for releasing us from the need to use a chest strap.

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Mio Slice Heart Rate Accuracy

I expected the Mio Slice to provide accurate heart rate monitoring and it did not disappoint. I have used the Slice now for 3 x bike rides and 2 x runs. Each time I have also used my Suunto Spartan Sport with a Bluetooth heart rate sensor (chest strap). The results of these comparison tests have been VERY GOOD. The example below shows the heart rate traces from a bike ride. The TOP one is the trace downloaded from my Garmin Edge 820. The heart rate was provided via ANT+ broadcast from the Mio Slice. The lower graph shows the heart rate trace acquired from my Suunto with a chest strap sensor. All my tests resulted in the same conclusion, the Mio Slice’s heart rate accuracy is VERY GOOD. I have awarded it 99%

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Broadcast Heart Rate (ANT+)

I  love the fact I can BROADCAST the heart rate to my Garmin Edge 820 via ANT+ protocol. Unfortunately I don’t seem to be able to broadcast in Bluetooth which would have been great. The broadcast of HR over ANT+ means I do not have to wear a chest strap to provide heart rate data to my Garmin Edge when out riding

Available in 4 Colours

How PAI works

The following images were taken during the installation of the PAI app.

An insight in to my first two weeks

The screen-grab below was taken from the Mio PAI app midway through my second week of testing the Slice. A large portion of my weekly PAI score of 110 is from Sunday. This was a 20 mile bike ride (Strava details) with an average HR of 146bpm and a maxHR of 171bpm. It was a reasonably hard ride with a strong headwind on the way home. Stave awarded it a SUFFER SCORE of 51. The Mio Slice awarded a PAI score of 64. As I suggested earlier, for those familiar with Strava’s SUFFER score, PAI is similar. It’s a different algorithm and they figures are NOT directly comparable.

The image below is a screen-grab of the heart rate data from that same bike ride. The PAI app splits the session in to zones of LOW, MEDIUM and HIGH intensity. Most of my PAI score (31 points) came from the time spent in the HIGH heart rate zone.


Devices Settings via the APP

The images below give an insight in to the level of settings that can be adjusted on the Mio Slice. Everything from smartphone notifications to screen brightness, wrist gestures and ANT+ heart rate broadcast can be set here.

You can even select what parameters are shown on the Slice’s display. I have chosen everything giving me access to Time, PAI, PAI today, Heart Rate, Steps, Calories, Distance and Sleep. I would like to have seen DATE as well? something I have asked the team at MioGlobal.

Conclusions and Review Summary

If I am totally honest, I was skeptical at first. However, having used the Mio Slice for a couple of weeks now I am totally on board. Anyone bored of achieving their daily step count with little effort looking for something more challenging, consider the Mio Slice. Anyone who achieves their daily step target but doesn’t see any obvious improvement in their physical fitness .. again, consider changing to a Mio Slice. The introduction of PAI to a fitness tracker is a ground breaking innovation. It may be precisely what we need to motivate the general public to a healthier lifestyle. It’s no surprise to me that it has come from the company that brought us strapless heart rate monitoring. Thanks Mio – GREAT JOB !!

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1) What is PAIMioglobal explain PAI


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A Brief History…

It all started in 1996. As a sports science student I wanted to promote the use of Heart Rate Monitors in exercise. The business went online in 1999. In 14 years we sold HRM's to over 300,000 customers.

After a short retail back we're now back with the new online store selling ONLY Polar. We still offer impartial advice & test other heart rate monitor brands. Our aim however, is to introduce you to Polar's products as an alternative to Garmin, Fitbit, Suunto or TomTom.

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