Fenix 5 Plus setup to last an Ironman

Hi,

Attempting to setup my fenix 5 Plus to last a full Ironman this coming weekend - it's likely going to be a slow one (14+ hours).

I'll be using a HRM-Tri throughout, on the bike a Vector 3 power meter and a speed sensor, then for the run both a Garmin food pod and temp sensors, with everything talking ANT+.

I plan to disable the normally recommend things: turn off bluetooth, wifi, backlight, have the bike and run activity GPS set to "GPS only" without secondary GLONASS or Galileo.

I do however have some questions others might have experience of:

My watch has lots of other sensors paired (mostly other bikes, foot pods, trainer etc) - will disabling these make any difference? My understanding is no, as it only looks for sensors during the first few minutes of each activity (and tested just now by activating my bike speed sensor after have a dummy cycling activity running for several hours = does not connect).
The optical HR is set to auto, which by my understanding means it will be off for the swim (always) then off for the rest as it'll pickup my HRM-Tri and favour this - correct?
Will disabling the Activity Tracking feature make any difference? I would assume yes to prolong battery life in general smartwatch mode, but perhaps negligible when recording an actual GPS-based activity?
Similarly the watch face - I can't see this making any difference unless it is on the screen, which it won't be during the activity?
Mapping - I don't plan on using any of the mapping features - will removing the map screens from my bike and run activities make any difference?
Music - again, will not be using this - is there anything here I need to disable?

I'm currently doing a rundown test - last night I fully charged then did just over an hours open water swim, then a few hours later started a cycling activity left running throughout the night (I've done 5.1km so far apparently!) and during which I've started to prune some of the settings like turning off bluetooth and wifi etc as I remembered - running total is around 11.5 hours with 32% remaining, so extrapolated out that is just under 17 hours. HOWEVER my main concern is this is with NO sensors connected (other than a temp it's picked up from my trainers in the garage!), with little movement throughout the night, and from memory it's when I'm cycling that it takes the biggest hit on the battery (the power meter perhaps?).

All experiences/ideas/thoughts welcomed! I'll also try another rundown test tomorrow during the daytime which might be a little more representative in terms of movement and maybe I'll wear the HRM-Tri, though don't think I'll be able to get in much cycling at this late stage!

(my plan b is to just not record the bike on the fenix - I can use an Edge 1030 for that - though ideally would like it all recorded on the fenix as a multisport activity if possible)

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0 Former Member over 5 years ago

SpikySimonW said:
Will disabling the Activity Tracking feature make any difference? I would assume yes to prolong battery life in general smartwatch mode, but perhaps negligible when recording an actual GPS-based activity?

I would say yes. Because, when I have Activity Tracking enabled, it counts my overall steps of the day (including the ones that are being recorded while being in an activity). So, the watch has to somehow also count them during an activity and I assume he uses the Gyroscope for that which would drain the battery. Maybe he only uses your stride length and the recorded kilometers to approximate it (this wouldn't drain the battery). But I doubt it. Anyway I would for sure disable Activity Tracking to increase battery life.

I also agree with you on all the other points. I assume non of them drain the battery if you're not using them (e.g. Music or Maps).

As a side note, while hiking I got to ~12hrs. of GPS tracking (with ~20% of battery left), but yes, without any external sensors connected. So I assume it would be less with sensors connected, but again what you already observed, it highly depends on the used sensor for sure.

Just a small tip that might help is, when the battery is at <10% you can switch to UltraTrac mode for the last 1-2hrs. this might get you over the finish line. Then your track might be less precise in the end but you get it fully recorded and you might be able to correct it afterwards on a computer.

SpikySimonW said:
The optical HR is set to auto, which by my understanding means it will be off for the swim (always) then off for the rest as it'll pickup my HRM-Tri and favour this - correct?

I would disable it just to be sure. For the running you have your HRM connected anyway, and for the bike you have your power meter...

0 maglodilevente over 5 years ago

Maybe not an option, but why don't you attach a small (1000-2000 mAh) power bank to the bike's handlebar and charge it during the activity?
I've seen many ultra runners with powerbank in the backpack's pocket, so you can be 100% sure it will last till the end of the race.

https://fellrnr.com/wiki/Charge_On_The_Run

0 matt.hallewell over 5 years ago in reply to maglodilevente

I did my first ironman about a month ago. Had similar concerns about my Fenix 5 plus lasting the distance. Happy to report that I finished in 12:40 with 11% charge left on my watch.

Agree with all of the proposed ideas to minimise battery usage. Only other thing I did was turn off the phone connection (whilst I didnt take my phone with me during the race, I didnt want my watch trying to connect to the phone for 12 hrs)

The other thing I considered was change the GPS mode to ultratrac mode during the back half of the run. I had decided beforehand that if the watch dropped to 10% charge, I would switch to ultratrac mode, but fortunately I didnt need to do that.

It might be also worthwhile disabling the onboard HR sensor altogether. Whilst your HRM-TRI should maintain a consistent ANT+ connection to the watch throughout the race, if it drops out for whatever reason, then you probably don't want the onboard HR sensor turning on and wasting battery.

Good luck with your race

0 SotirisAnagnostopoulos over 5 years ago

I would recommend the powerbank solution. Recently, I participated in a 100K Ultra race with GPS+Glonass and navigation. No other sensor enabled. I charged the F5+ on the go on 16% and after 10 hours approximately. A very small powerbank is light and will do the job.

0 SpikySimonW over 5 years ago

Thanks for all the input.

My rundown test yesterday resulted in around 16 hours, though as noted with no sensors connected and little movement overnight. Follow that I also did a mini duathlon yesterday evening (roughly 20 minutes running, 40 minutes cycling) and with sensors connected (HRM-Tri, footpod, temp, and power meter on the bike) which appeared to burn through approx. 6% of battery over the hour duration.

I've decided to ditch the footpod and temp sensors for race day - both non-essentials - I should still get reasonable pacing info from the accelerometers in the watch itself (good enough to track a steady marathon pace). I also remembered I might have been getting confused between power drain from my Vector 3 power meter and a Shimano D-Fly - I added both to my bike around the same time and saw a noticeable hit in Garmin head unit battery life - the bike I used last night didn't have its D-Fly paired to my watch and I didn't see any significant additional power drain from the power meter alone beyond what I'd seen during the day (albeit this was very short test). Again, Di2 info isn't exactly essential for my historical data files (!) therefore the D-Fly will be disabled for race day.

I've taken onboard the comments re. disabling Activity Tracking and the Optical HR, having done this I've started another rundown test today - this time with the HRM-Tri connected. Will report back.

(goes to show the impact you can have on battery life by paying attention to and understanding the various settings.. just a few months ago I did a Half Ironman and without any thought put into my watch other than ensuring it was charged overnight - with everything "on", connected to everything and with all the fancy features enabled I seem to remember I finished the event in 5-odd hours with very little battery left!!)

+1 SpikySimonW over 5 years ago

Follow-up: my finish time was just under 13 hours, with the watch showing 19% battery remaining = very pleased with the watch, it did its job and upon starting the run left me with no worries it would last the duration (I had my old fully charged fenix 3 waiting in my T2 transition bag just in case it was looking a bit close!). I did notice my instant pace was slightly more erratic than normal (ie. missing the footpod) and, from someone who likes to capture all their data, it is a tiny bit annoying I logged no activity tracking related steps, active minutes etc that day, so if I find the time I'd like to experiment with how much of an impact turning back on the activity tracking and pairing an additional ANT+ sensor actually has, but bottom line being I can confirm, when carefully configured, a fenix 5 Plus is capable of lasting a full Ironman distance race (I'd project even close to the normal 16hr cut-off).

0 Ocean5 over 5 years ago in reply to SpikySimonW

Congrats on finishing, great achievement!

In relation to the 5 plus, it seems like a step down from original 5 series in terms of battery life. My IM took about the same 13 hours and I had 48% left with fenix 5. Garmin should focus more on sporting and less on music/payments... or give us a few options with bigger battery but e.g. no music.

0 matt.hallewell over 5 years ago in reply to SpikySimonW

Congratulations to both you and your Fenix 5+ Great to see that the training and preparation that both you and the watch did paid off on race day!

Out of interest, did you end up using any external ANT+ sensors connected to your watch? Power meter on bike or HRM?

I reckon that 19% battery remaining in 13 hours is pretty close to the advertised battery life specs.

For all the Garmin bashing many of us have done about battery life of the Fenix 5+, its re-assuring to see that when it really matters most (in a long distance race), that the battery works pretty much as advertised.

0 Former Member over 5 years ago in reply to Ocean5

Agreed, but the trouble is that the majority of buyers of the watch are not Ironperson competitors, but rather amateur joggers who just want to listen to a few tunes and buy a coffee with their wrist after their weekend 5km. They're the ones bringing the money and driving the development.

0 Dr Phil over 5 years ago in reply to Former Member

not Ironperson competitors

The competition is 'Ironman'. They are all Ironman competitors. Whether we like it or not, whether the competitors like it or not, every person completing an Ironman branded event is an Ironman. It's totally wrong to say anything else.

That said

Ocean5 said:
Garmin should focus more on sporting and less on music/payments... or give us a few options with bigger battery but e.g. no music.

I agree. There's too much 'fluff' being added but you don't have to use music, or any of the other 'advanced' features of the watch. If you don't, and use it with only GPS (no augmented service) and WHR only, you'll get close to the 'up to' specs.

I'm one of those grumpy old gits who cannot understand why anyone wants to run with stuff plugged into their ears, plus I get really, really annoyed when I'm trying to pass someone on a trail and they either can't hear me or choose to ignore when I politely advise them that I want to pass when it's clear to do so. I do sometimes listen to music from the watch when I'm walking home just because I can though.