Power is still relatively new for runners. And while there are some apps that cover most of the important metrics, you may find that you need additional apps to plug the gaps.
Here are a few apps that can fill those gaps.
𝐔𝐬𝐢𝐧𝐠 𝐀𝐩𝐩𝐥𝐞 𝐰𝐫𝐢𝐬𝐭-𝐛𝐚𝐬𝐞𝐝 𝐩𝐨𝐰𝐞𝐫
Apple Health doesn’t provide any of the important metrics.
Which means you’ll need to transfer your workout data from Apple Health into an app that can provide these, like WKO or Intervals.icu.
There are a few apps that will do this. I’ve successfully used HealthFit; other options are RunGap or Health Sync.
𝐑𝐮𝐧𝐧𝐢𝐧𝐠 𝐄𝐟𝐟𝐞𝐜𝐭𝐢𝐯𝐞𝐧𝐞𝐬𝐬 (𝐑𝐄)
The only app to provide this (natively) is WKO.
If you’re a Stryd user, or if you’re using Intervals.icu, you’ll need to calculate RE manually or use SuperPower Calculator for Sheets (SPCs).
‘Getting Started’ covers other apps that can calculate power metrics, while the book’s online content provides a more complete comparison of Power Apps.
Intervals.icu analyses your rides, runs, swims and other activities (with and without power). It provides basic and advanced analytics and planning in an easy-to-use web interface with support for desktops, phones, and tablets. Intervals.icu is free to use, with additional features should you choose to subscribe.
✅ Threshold Power. Intervals.icu can calculate threshold power (using your choice from several models) based on the last 90 days of completed workouts or using a custom date range.
✅ Training Load Score. Intervals.icu uses the term ‘Training Stress Score’ (TSS) and can calculate a power-based TSS for each completed workout.
✅ Training Load Balance. Intervals.icu uses the term ‘Form’ to show the balance between ‘Fitness’ and ‘Fatigue’.
✅ Ramp Rate. Intervals.icu shows your week-on-week Ramp Rate (RR), overlaid on the same chart as fitness, fatigue and form.
✅ Running Effectiveness. Intervals.icu doesn’t calculate Running Effectiveness, although you can manually calculate this using the detailed workout review pages, or by adding a custom calculation.
𝐖𝐡𝐲 𝐮𝐬𝐞 𝐈𝐧𝐭𝐞𝐫𝐯𝐚𝐥𝐬.𝐢𝐜𝐮?
If you’re not using the Stryd ecosystem or TrainingPeaks/WKO, Intervals.icu is a great way to track your power metrics.
‘Getting Started’ covers other apps that can calculate power metrics, while the book’s online content provides a more complete comparison of Intervals.icu vs. other Power Apps.
✅ Threshold Power. WKO uses the term ‘Functional Threshold Power’ (FTP) and offers an automatically calculated FTP, as well as the option to manually record your FTP history (and use it in charts).
✅ Training Load Score. WKO uses the term ‘Training Stress Score’ (TSS).
✅ Training Load Balance. WKO uses the term ‘Training Stress Balance’ (TSB).
✅ Ramp Rate. WKO can chart your week-on-week Ramp Rate (RR).
✅ Running Effectiveness. WKO can show your Running Effectiveness (RE) for an entire workout or just for part of a workout (e.g. an interval).
𝐖𝐡𝐲 𝐮𝐬𝐞 𝐖𝐊𝐎?
WKO comes with hundreds of pre-configured charts. You can also build your own charts and calculated metrics using a powerful charting language. WKO integrates seamlessly with TrainingPeaks, syncing planned and completed workout data and a range of health metrics.
‘Getting Started’ covers other apps that can calculate power metrics, while the book’s online content provides a more complete comparison of WKO vs. other Power Apps.
In the following, the term ‘Stryd’ includes Stryd PowerCenter and Stryd Mobile
✅ Threshold Power. Stryd uses the term ‘Critical Power’ (CP) and offers an automatically calculated CP (Auto-CP) as well as a manually-set CP (using various protocols).
✅ Training Load Score. Stryd uses the term ‘Running Stress Score’ (RSS) and offers a unique calculation which includes a term representing the additional biomechanical stress put on your body from running (vs. cycling).
✅ Training Load Balance. Stryd uses the term ‘Running Stress Balance’ (RSB) and offers guidance for how to interpret your RSB.
❌ Ramp Rate. Stryd does not show your Ramp Rate (RR). You’ll need to calculate RR manually using Stryd’s 42d Avg (in Stryd Mobile) or use another system to track this.
❌ Running Effectiveness. Stryd does not show your Running Effectiveness (RE). You’ll need to calculate RE manually using another system, or use one of Stryd’s alternate metrics – for example Form Power, Leg Spring Stiffness, Impact Loading Rate.
𝐖𝐡𝐲 𝐮𝐬𝐞 𝐒𝐭𝐫𝐲𝐝 𝐏𝐨𝐰𝐞𝐫𝐂𝐞𝐧𝐭𝐫𝐞 / 𝐌𝐨𝐛𝐢𝐥𝐞?
The Stryd ecosystem is probably the most power-friendly app at the moment, designed with power in mind, and aimed at runners who are getting started with power.
‘Getting Started’ covers systems that can calculate the missing metrics, while the book’s online content provides a more complete comparison of Stryd vs. other Power Apps.
Power is a complete system using effort as its fundamental metric.
Power uses your second-by-second effort from completed workouts to calculate metrics that build a detailed picture of your running capabilities.
Imagine you run 3 times per week for around an hour each time. That’s 60 pieces of data per minute, 3600 per hour and for 3 runs, over 10,000 pieces of data. That’s a lot of data!
Which is why power relies on power-aware applications (‘apps’) to calculate your metrics.
𝐂𝐚𝐧 𝐲𝐨𝐮 𝐮𝐬𝐞 𝐚𝐧𝐲 𝐚𝐩𝐩?
The choice is yours, but some apps are more power-aware than others, with the best apps able to calculate the most important metrics.
✅ Training Load Score. A score (per workout) that combines ‘how hard?’ and ‘how long?’ – represents the workout’s metabolic stress, its impact on your body.
✅ Training Load Balance. Indicates whether your training is ‘productive’ – enough stress to encourage adaptations, but not so much that there is a greater risk of injury or over-training.
✅ Ramp Rate. Replaces ‘the 10% rule’ with a metric based on your training load scores – to monitor whether you’re adding training load too quickly.
✅ Running Effectiveness. Measures how effectively you convert power into speed – used to estimate finish times, to assess changes to your running form and to evaluate your fatigue resistance.
There are other criteria that will influence your choice of apps, but being able to calculate these metrics is key.
All sports watch brands (and the Apple Watch) offer wrist-based power, but it works better with some brands than others (using the Which Watch? criteria).
Unfortunately, I haven’t been able to try all brands to understand what works and what doesn’t.
I’ve tried COROS and Polar – here’s what I’ve found.
𝐂𝐎𝐑𝐎𝐒 𝐰𝐚𝐭𝐜𝐡𝐞𝐬
All COROS watches support wrist-based running power with no additional on-watch apps, but: ❌ you must plan workouts in the companion app, in TrainingPeaks, in Final Surge or in Intervals.icu. ❌ the companion app does not provide power-based metrics – see below.
𝐏𝐨𝐥𝐚𝐫 𝐰𝐚𝐭𝐜𝐡𝐞𝐬
Polar watches will display power while running and record power to workout files, but: ❌ You must plan workouts in the Polar Flow app, or in TrainingPeaks. If you use structured workouts, TrainingPeaks may be the better choice (although you’d need to subscribe to the premium option). ❌ The system does not support structured workouts (although you can build workouts with phases). ❌ the Polar Flow app does not provide power-based metrics – see below.
𝐏𝐨𝐰𝐞𝐫-𝐛𝐚𝐬𝐞𝐝 𝐦𝐞𝐭𝐫𝐢𝐜𝐬
None of the manufacturers provide power-based metrics that would enable you to calculate your threshold, monitor your training, and plan your events and races.
Your app choices are TrainingPeaks/WKO or Intervals.icu.
𝐈𝐟 𝐮𝐬𝐢𝐧𝐠 𝐰𝐫𝐢𝐬𝐭-𝐛𝐚𝐬𝐞𝐝 𝐩𝐨𝐰𝐞𝐫
✅ Ideally: use a Connect IQ 5.0.0 Garmin watch, a COROS watch, or an Apple Watch with the Watchletic app. ✅ Try to avoid: using a Polar watch ✅ I haven’t tried: using a Wahoo or Suunto watch, or other brands like Amazfit or Google Pixel.
Stryd works with all sports watches, but it works better with some than others (using the Which Watch? criteria).
𝐂𝐎𝐑𝐎𝐒 𝐰𝐚𝐭𝐜𝐡𝐞𝐬
✅ COROS watches (except the Pace 1 and kiprun series) meet all the criteria using native watch functionality.
𝐖𝐚𝐡𝐨𝐨 𝐰𝐚𝐭𝐜𝐡𝐞𝐬
The Elemnt Rival meets all the criteria using native watch functionality, except: ❌ You must plan workouts in third-party apps like TrainingPeaks or Intervals.icu. You cannot download workouts planned in the Stryd ecosystem to the watch.
𝐒𝐮𝐮𝐧𝐭𝐨 𝐰𝐚𝐭𝐜𝐡𝐞𝐬
Suunto watches will display power while running and record power to workout files for upload to the Stryd ecosystem, but: ❌ You must plan workouts in the Suunto app or in third-party apps like TrainingPeaks or Intervals.icu. You cannot download workouts planned in the Stryd ecosystem to the watch. ❌ Additional Stryd metrics require a manual offline sync (for each completed workout) to transfer them to the Stryd Ecosystem.
𝐏𝐨𝐥𝐚𝐫 𝐰𝐚𝐭𝐜𝐡𝐞𝐬
Polar watches will display power while running and record power to workout files for upload to the Stryd ecosystem, but: ❌ You must plan workouts in the Polar Flow app or in TrainingPeaks. If you use structured workouts, TrainingPeaks may be the better choice (although you’d need to subscribe to the premium option). ❌ The system does not support structured workouts (although you can build workouts with phases). ❌ Additional Stryd metrics require a manual offline sync (for each completed workout) to transfer them to the Stryd Ecosystem.
𝐎𝐭𝐡𝐞𝐫 𝐛𝐫𝐚𝐧𝐝𝐬
Stryd continues to work with watch providers and lists all watches that can be used to Run with Power using a Stryd footpod on their website.
𝐈𝐟 𝐮𝐬𝐢𝐧𝐠 𝐚 𝐒𝐭𝐫𝐲𝐝 𝐟𝐨𝐨𝐭𝐩𝐨𝐝
✅ Ideally: use an Apple Watch, a Connect IQ 5.0.0 Garmin watch, or a COROS watch ✅ If you must: use a Wahoo watch ✅ Try to avoid: using a Suunto or Polar watch
The Stryd Zones datafield is your best choice – it’s fully compatible with Garmin watches running Connect IQ 5.0.0 or later. Stryd Zones: ⌚ Downloads workouts planned in the Stryd Ecosystem (via Garmin Connect) ⌚ Can show various power numbers while running ⌚ Records power (second-by-second) into your workout file ⌚ Uploads completed runs into the Stryd Ecosystem (via Garmin Connect) ⚡ Supports Structured Workouts ⚡ Provides 3s, 10s, and 30s Power Smoothing ⚡ Provides current and last Lap Averages.
If you have an older watch (running Connect IQ 3.0.0 through 4.x.x), you’ll need to use the Stryd Workout app (for Garmin) to run Structured Workouts.
𝐆𝐚𝐫𝐦𝐢𝐧 𝐰𝐢𝐭𝐡 𝐖𝐫𝐢𝐬𝐭-𝐛𝐚𝐬𝐞𝐝 𝐏𝐨𝐰𝐞𝐫
The watches listed at Garmin; Running Power Device Requirements in the section ‘Watch Models That Support Native Running Power’ support Wrist-based power, using Garmin’s ‘Run’ app.
Unfortunately, the watches listed in the section ‘Watch Models That Support Running Power With a Connect IQ App‘ (my italics) did not provide repeatable and concurrently valid results when I studied their output. For that reason, I cannot recommend Garmin’s ‘Power’ datafields.
Garmin’s native running power implementation (on newer watches) meets the criteria but note that: ❌ Garmin only offers 10s smoothing. This makes it less useful when running short-duration intervals. Fortunately, it’s possible to use a 3rd-party datafield (like pbRun) to achieve a shorter smoothing interval. ❌ While you can use Garmin Connect to plan your workouts, it does not provide power-based metrics that would enable you to calculate your threshold, monitor your training, and plan your events and races. You’ll need to connect a 3rd-party reviewing app to Garmin Connect to obtain metrics.
Instead, I’d recommend the pbRun datafield, which: ⌚ Relies on Garmin Connect to download planned workouts, making them available to any app connected to Garmin Connect ⌚ Can show real-time and lap power numbers while running ⌚ Records power (second-by-second) into your workout file ⌚ Relies on Garmin Connect to upload completed workouts, making them available to any app connected to Garmin Connect ⚡ Supports Structured Workouts ⚡ Provides 3s, 5s, 10s and 30s Power Smoothing ⚡ Provides current and last Lap Averages
Stryd’s Workout app is the obvious choice – it’s fully compatible with the Apple Watch Ultra, SE or series 3 or later. The Stryd Workout app: ⌚ Downloads workouts planned in the Stryd Ecosystem ⌚ Can show various power numbers while running ⌚ Records power (second-by-second) into your workout file ⌚ Uploads completed runs into the Stryd Ecosystem (and from there into other review apps) ⚡ Supports Structured Workouts ⚡ Provides 3s, 10s, and 30s Power Smoothing ⚡ Provides current and last Lap Averages.
There is another choice – Watchletic (see below) can be used in place of the Stryd Workout app, for example if you want to use another planning or review app than the Stryd PowerCenter.
𝐀𝐩𝐩𝐥𝐞 𝐖𝐚𝐭𝐜𝐡 𝐰𝐢𝐭𝐡 𝐖𝐫𝐢𝐬𝐭-𝐛𝐚𝐬𝐞𝐝 𝐏𝐨𝐰𝐞𝐫
The Apple Workout app isn’t the best choice for Running with Power, as it doesn’t: ❌ record second-by-second data into your workout file ❌ display lap power ❌ offer power smoothing ❌ upload completed workouts into a power-based reviewing app
Instead, I’d recommend the Watchletic app, which: ⌚ Downloads workouts planned in the IOS Watchletic app or in a number of other planning apps (TrainingPeaks, Final Surge, Stryd, Intervals.icu etc.) ⌚ Can show real-time and lap power numbers while running ⌚ Records power (second-by-second) into your workout file ⌚ Uploads completed runs into Apple Health or into a number of other reviewing apps (TrainingPeaks, Final Surge, Stryd, Intervals.icu etc.) ⚡ Supports Structured Workouts ⚡ Provides 3s and 10s Power Smoothing ⚡ Provides current Lap Average – it doesn’t (yet) provide last lap average.
Note that the downloads from and uploads to the apps listed above are a premium feature, available with a paid monthly subscription.
At a minimum, you’ll need a power meter and a running watch. Or you could combine the two using a watch with wrist-based power.
But which watch should you choose?
Are there any that make Running with Power easier? Not easier to run, just easier to use power when running?
𝐖𝐚𝐭𝐜𝐡 𝐜𝐫𝐢𝐭𝐞𝐫𝐢𝐚
The 𝑚𝑖𝑛𝑖𝑚𝑢𝑚 criteria are: ⌚ Download. Able to download planned runs to your watch with minimal manual effort ⌚ Display Power. Able to show power while running ⌚ Record Power. Able to record power (second-by-second) into your workout file ⌚ Upload. Able to upload completed runs from your watch with minimal manual effort
These 𝑎𝑑𝑑𝑖𝑡𝑖𝑜𝑛𝑎𝑙 criteria (if met) will improve your experience when Running with Power: ⚡ Structured Workouts. You can execute workouts with multiple steps and power targets/alerts on your watch – rather than having to remember steps/targets or write them on your hand. ⚡ Power Smoothing. The power numbers can be smoothed by averaging real-time power values over 3, 5 or 10 seconds – replacing ‘spiky’ power numbers and reducing above/below target alerts. ⚡ Lap Averages. You can display the average power for the current lap on-screen – to monitor whether you’re meeting workout power targets.
𝐖𝐚𝐭𝐜𝐡 + 𝐏𝐨𝐰𝐞𝐫 𝐦𝐞𝐭𝐞𝐫
The posts linked below assess Apple and Garmin watches using the above criteria, then switch that around to assess other watches from the perspective of the Stryd footpod and Wrist-based power.
