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W' Balance (W Prime Balance)


This data field display your W' Balance (%) live during a ride. This value is displayed into the GoldenCheetah software, and well described on the video here: </p><p></p><p>Check all the details on my blog:</p><p></p><p>It needs 3 parameters: your Wprime value (in joules) and your Critical Power (CP) in watts. You can choose also the formula used to compute the data (starting with version 1.2). Use GoldenCheetah to help you find the correct values if you don't know them. Of course, a compatible powermeter is required.</p>

What’s New

What's new with version 2.1.2:</p><p>- Support Edge 530/830</p><p>- Support all MARQ models</p><p>- Support Forerunner 945</p><p></p><p>What's new with version 2.1.1:</p><p>- Support Edge 130</p><p></p><p>What's new with version 2.0.0:</p><p>- Values are now stored in the .fit file of activity and a graph is available in GC</p><p></p><p>What's new with version 1.6:</p><p>- Support Edge 1030</p><p></p>

Additional Information


This app requires access to:

  • Run in the background when it is not active (potentially affecting battery life)
  • Record additional information into activity files
  • D2™ Bravo D2™ Bravo
  • D2™ Bravo Titanium D2™ Bravo Titanium
  • D2™ Charlie D2™ Charlie
  • D2™ Delta D2™ Delta
  • D2™ Delta PX D2™ Delta PX
  • D2™ Delta S D2™ Delta S
  • Descent™ Mk1 Descent™ Mk1
  • Edge® 1000 Edge® 1000
  • Edge® 1030 Edge® 1030
  • Edge® 1030, Bontrager Edge® 1030, Bontrager
  • Edge® 130 Edge® 130
  • Edge® 520 Edge® 520
  • Edge® 520 Plus Edge® 520 Plus
  • Edge® 530 Edge® 530
  • Edge® 820 Edge® 820
  • Edge® 830 Edge® 830
  • Edge® Explore Edge® Explore
  • Edge® Explore 1000 Edge® Explore 1000
  • Edge® Explore 820 Edge® Explore 820
  • epix™ epix™
  • ForeAthlete® 735XTJ ForeAthlete® 735XTJ
  • ForeAthlete® 920XTJ ForeAthlete® 920XTJ
  • Forerunner® 735XT Forerunner® 735XT
  • Forerunner® 920XT Forerunner® 920XT
  • Forerunner® 935 Forerunner® 935
  • Forerunner® 945 Forerunner® 945
  • fēnix® 3 fēnix® 3, quatix® 3, tactix® Bravo
  • fēnix® 3 HR fēnix® 3 HR
  • fēnix® 5 fēnix® 5, quatix® 5
  • fēnix® 5 Plus fēnix® 5 Plus
  • fēnix® 5S fēnix® 5S
  • fēnix® 5S Plus fēnix® 5S Plus
  • fēnix® 5X fēnix® 5X, tactix® Charlie
  • fēnix® 5X Plus fēnix® 5X Plus
  • fēnix® Chronos fēnix® Chronos
  • MARQ™ Adventurer MARQ™ Adventurer
  • MARQ™ Athlete MARQ™ Athlete
  • MARQ™ Aviator MARQ™ Aviator
  • MARQ™ Captain MARQ™ Captain
  • MARQ™ Commander MARQ™ Commander
  • MARQ™ Driver MARQ™ Driver
  • MARQ™ Expedition MARQ™ Expedition
Average Rating: (28 Ratings)

June 23, 2019 | Version 2.1.2

Seems to accurately reflect what I'm feeling. It's nice to see how my energy is used. What's the app shown on the picture of the 520 with the data field "matches"?

Omar Awad
April 21, 2019 | Version 2.1.1

I absolutely love knowing how much fuel is left in the tank and when I’m ready for another tough effort

Felipe Moreno Landete
January 15, 2019 | Version 2.0.0-upd2

Great app! Congrats to the developer. Trying to solve some doubts: 1- Calculate CP and W’ personalized values. In GC---Tools---CP and W’ Estimator. Input your 5’ and 20’ w values (do a test in advance). For example, 5’ @325 and 20’ @291 gives you CP=280, W’=14000. 2- Include CP and W’ in GC. Tools---Options---Athlete Tab---Power Zones tab. Add new (“+” button). Include date, CP and W’. You may also want to include FTP, to simplify typically same as FTP. Below it will appear your calculated power zones (in 7 thresholds). 3- Include CP and W’ in Garmin Device. In Garmin Connect Mobile App, go to More button at the bottom right hand side of the screen. Then Garmin Devices---Select your device (i.e. Edge 520)---IQ Connect Apps---Data Fields---W’Balance. Here you have the app installed and you can manually overwrite default values (250 and 20000) with your own. In the example 280 and 14000. Do this in each of the devices where you have this app installed. You may also want to match the calculation method on how W’ is used and recharged in Garmin and GC, so you get the same figures while riding and when analysing. In Garmin, in the same screen as step 3, set the method to Integer, as suggested by the developer, using Dr. Skiba method. In GC, go to Tools---Options---General Tab---W’Balance formula. In you prefer Froncioni method, set both Garmin and GC to Differential. 4- You may also want to have same power zones in GC (see step 2) and in Garmin. To do so, go to the Garmin Connect Mobile App (not PC, doesn’t work for me at least)---More button---Garmin Devices---Edge 520---User Configuration---Power Zones and manually input the same info as in GC Synchronize and you are done!

Troy Williams
September 11, 2018 | Version 2.0.0-upd2

I have managed to get a result of negative 30 when doing long hard climbs. On one occasion have even got down to negative 40. Is this correct? - how do i interpret this number? Hope you can help

July 19, 2018 | Version 2.0.0-upd2

Super App, fait ce qu'on lui demande, génial le graph sur Gconnect !

Matthew Grant
July 11, 2018 | Version 2.0.0-upd2

Hi, like a previous reviewer I am also unable to change the default values. I have amended them in Garmin Express and the SYNC has completed succesfully but it still displays 250watts 20000kj on the device. I am using an EDGE 520 on FW V12.60.

July 10, 2018 | Version 2.0.0-upd2

How on earth do you update the W' Value? It displays a default 20000 but Golden Cheetah has be at 31800

June 11, 2018 | Version 2.0.0-upd2

Garmin Express in Windows PC

May 17, 2018 | Version 2.0.0-upd

Hello I am testing the application, but it does not let me change the default values. Always appear 250 W and 20000 joules. Although you save and synchronize with Garmin Edge 1030 Greeting

Developer Reply
May 17, 2018, nakan

This is most probably related to a bug or sync issue of the parameters. Are you changing the parameters in Garmin Express on Mac or PC or with the mobile app ?

Félix Moulin
March 20, 2018 | Version 2.0.0

Bravo pour cette application ! Un petit soucis cependant mon pourcentage ne revient pas toujours à 100% une fois que j'enregistre mon activité et en relance une autre le lendemain ... Tu sais d'où peux venir le problème ?

Developer Reply
March 20, 2018, nakan

Non, c'est étrange. Je vais regarder de mon côté si je constate ce genre de problèmes. Dans mon code les données sont clairement remises à 0 pour une nouvelle activité en tout cas.

February 9, 2018 | Version 2.0.0

Hi. I just tried this today. I noticed that the I didn’t get data for the power graph in my garmin connect. I an using a Garmin 520. Is the developer aware of this? Are there any fix for this? Regards

Developer Reply
February 12, 2018, nakan

Hi, The fact that the power data is not available in GC is not related to this IQ Datafield, as it will only add a new data plot but not replace or substitute anything. Best.

DONNAY Jean Francois
February 4, 2018 | Version 2.0.0

Bien vu le graph incorporé à Connect

November 30, 2017 | Version 1.6-upd

Great tool. it's cool to see a value corresponding to the pain in my muscles during Vo2max intervalls. It also pushes me further during hard intervalls, cause I see, that there is some power left - against my feeling. It's also cool to see the FTP rising when W'bal gets negative. All in all a cool tool. Thanks :-)

DONNAY Jean Francois
October 7, 2017 | Version 1.6

La seul info indispensable lorsque l'on roule avec un capteur de puissance TOP Comme la réactivité du dévellopeur The one and only essential info when riding with a power sensor                                                 TOP                             As the reactivity of the developer

DONNAY Jean Francois
October 2, 2017 | Version 1.5-upd

Bonjour, cette application sera t elle bientôt disponible pour l'Edge 1030 ?

Developer Reply
October 6, 2017, nakan

Bonjour. La version 1.6 qui vient d'être publiée support désormais le Edge 1030! Sportivement.

Michael Haas
June 27, 2017 | Version 1.5

Perfect app, everything what we need. Please show the given CP value in the heading. Greetings Michael [email protected]

Timo Heister
May 4, 2017 | Version 1.5

Very cool being able to take advanced statistics I normally only look at in GoldenCheetah out on the road.

Mark McFadyen
April 15, 2017 | Version 1.5

I love the idea of using this for races. I have an issue with how it works on my 520 though. The values were not going down fast enough. When I compared the Golden Cheetah file, I was down to like 5.4 Kj remaining after a hard climb, where during the ride it displayed like high teens to 20 kj left. I thought I was being weak. I think I loaded the CP and W' data points accurately.

Developer Reply
April 16, 2017, nakan

Hi, Thanks for the feedback. Are you sure you are using the same algorithm in the data field and GC (differential or integral) ? This may be the explaination. Cheers.

DONNAY Jean Francois
February 25, 2017 | Version 1.4-upd1

Fonctionne parfaitement et permet de bien se gérer. Au début je le regardais après coup pour confirmer mes impressions et parfois on s'aperçoit qu'on peut en remettre un peu. Attention il faut que ses paramètres soit parfaitement configurer dans GC (que la FTP soit juste est primordial) pour avoir des enfants infos au plus près de la réalité. Good job :-)

October 1, 2016 | Version 1.4-upd

après essai en bosse 55km 900m de deniv pas mal du tout je me fixe d arrive a 90% au pied des bosses alors que j étais a 45% du réservoir 10mn avant c est assez bluffant quand on sait bien ce servir du capteur

June 28, 2016 | Version 1.31

Work for many devices, have setup formula, full compatible with GoldenCheetah

Ian Spivack
March 28, 2016 | Version 1.1

same comments as another person. Seems like there is a math problem: The calculation in the app deviates from the Golden Cheetah program. The W' expended is less than calculated by GC, and the recharge of W' is to slow.

Filipe Oliveira
March 27, 2016 | Version 1.1

Absolutely perfect. This is why I purchased the Edge 520. Clear display of remaining W'Bal % in a font as big as any other data field. Thank you.

Nichlas Holmén
March 25, 2016 | Version 1.1

The calculation in the app deviates from the Golden Cheetah program. The W' expended is less than calculated by GC, and the recharge of W' is to slow.

Martin Hillion
March 14, 2016 | Version 1.1

No issues found installing or configuring v1.1 Still pending to take the Garmin out for a spin to see it in action.

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