Question 1

How long is battery life?

Accepted Answer

Depends on how you use it. If you have prolonged sessions, less time. If you have solar and outside, a little longer.

Question 2

Is the $100 extra solar version worth it so far?

Accepted Answer

In the northern hemisphere - so far no, but I’m looking fwd to the spring days

Question 3

How big is the screen ?

Accepted Answer

I had own the 935, the 945 and now I bought the 955. The screen is as big as a regular smart watch - but the watch it self is not cumbersome as those bigger ones from Garmin. The OS that comes is really great and innovative, with the Morning Summary telling you abou your Readyness based on Trainning Status, Sleep Score and. HRV dynamics. The screen is more than enough to see alerts, messages and all the info - with the new touch screen system - stable and reliable

Question 4

Is Training readiness accurate . How does it compare to body battery?

Accepted Answer

The training readiness score seems very accurate to me. I'm fairly old, and work out 6-7 days/week. I must decide how hard/easy to hit it on my cross-training days so I'm good for my run days (my main thing), and whether I should cross-train on Sunday or take day off. The training readiness score is derived from 6 metrics: Sleep Score, Recovery Time (remaining from previous activity), HRV status, Acute load, Sleep score history, stress history. I find these underlying metrics to be accurate. I see direct correlation with "Training Readiness" vs how I actually feel, how well I rested, how hard I hit it the day before, etc. 
It takes the watch a couple weeks to really "learn" you, and in my case, I think it took my age into consideration and under-estimated what I could handle - kept yelling at me about over training. But it caught on in about 10-14 days and seems very very accurate.

As to the diff between training readiness vs body battery, I'll just quote from DC Rainmaker's review on his site:
"Body Battery is basically your energy level. You recharge it every night, and then decrease it during the day, or during periods of relaxation (like sitting on the couch watching TV). However, with the Forerunner 955 there’s also Training Readiness, which is aimed at figuring out if you should train (or, to what intensity).
Think of it like this: Use Body Battery on vacation to see the impacts of your day when you don’t care about training. Whereas, use Training Readiness when you are trying to get workouts in. Again, tons more later on this in the ‘Training Readiness’ section."
 
end quote.
I personally use both in conjunction, training or not. In the rare case that I drink alcohol to mild excess, it shows up in poorer sleep score, higher stress score, ergo lower body battery and lower training readiness. This helped me to stop thinking of the night before an easy training day as a "cheat day" where I go out and party too much, to a "recovery day" - it really shows up. Its like having a "mom" or coach that tells you what you should/shouldn't do, and backs it up by the metrics it reads from your actual body. You can't argue with it, so it helps you improve your habits during those periods where you are serious/dedicated to meet certain weight or (in my case) race/time goals. 
It is actionable data upon which you can reliably make sound decisions about how/whether to train, and how hard you should do so. And if you start to go astray, it clearly shows the effects of your fun-loving ways. 
My old Garmin 935 was such a great watch. I can't believe this new watch is such a huge improvement over that - the algorithms are more refined, more accurate. I always reveled in my old 935 telling me my "fitness age" was 20+ years lower than my actual age (puff chest, beat like ape) but always knew that was BS. This watch is giving me 10 years lower than my actual age. I don't like it, dang it, but its closer to the truth.

ASIN	B09WT9PF2N
Additional Features	Bluetooth
Age Range Description	Adult
Band Material Type	Silicone
Band Width	22 Millimeters
Battery Average Life	20 days
Battery Capacity	342
Battery Cell Type	Lithium Polymer
Battery capacity	342
Best Sellers Rank	#120,065 in Sporting Goods ( See Top 100 in Sporting Goods ) #111 in Sports GPS Units #27,656 in Running Equipment
Brand	Garmin
Built-In Media	Forerunner 955; Charging/data Cable; documentation
Closure Type	Buckle
Color	Black- Solar
Communication Feature	Bluetooth
Compatible Devices	Smartphone
Compatible Phone Models	Compatible with iOS and Android
Connectivity Technology	Bluetooth, USB
Connectivity technology	Bluetooth, USB
Controller Type	Push Button
Customer Reviews	4.6 out of 5 stars 1,784 Reviews
Display Type	OLED
GPS Geotagging Functionality	Built-in GPS
Global Trade Identification Number	00753759297008
Human Interface Input	Buttons, Touchscreen
Item Dimensions	46 x 46 x 15 millimeters
Item Type Name	Running Smartwatch
Item Weight	1.9 Ounces
Manufacturer	Garmin
Memory Storage Capacity	32 GB
Memory storage capacity	32 GB
Metrics Measured	Heart Rate Monitor, Sleep Duration, Distance, Step Count, Calories Burned
Model Name	Forerunner 955
Model Number	010-02638-00
Operating System	[Proprietary]
Operating system	[Proprietary]
Resolution	396 x 484
Screen Size	1.3 Inches
Shape	Round
Special features	Bluetooth
Sport Type	Triathlon
Style Name	Solar
Supported Application	Fitness Tracker
Supported Satellite Navigation System	GPS
UPC	753759297008
Water Resistance Depth	50 Meters
Water Resistance Level	Water Resistant
Wearable Computer Type	Smart Watch
Wireless Compability	Bluetooth
Wireless communication standard	Bluetooth

Garmin Forerunner® 955 Solar, GPS Running Smartwatch with Solar Charging Capabilities, Tailored to Triathletes, Long-Lasting Battery, Black - 010-02638-00

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