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.

Operating System	iOS, Android
Touch Screen Type	Capacitive
Display Type	Sunlight-visible, Transflective Memory-in-Pixel (MIP)
Human-Interface Input	Touchscreen, Buttons
Compatible Devices	Smartphone
Are Batteries Included	Yes
Supported Satellite Navigation System	GPS
Connectivity Protocol	Bluetooth, USB
Sport Type	Training, Track & Field, Exercise & Fitness, Running, Outdoor Lifestyle
Audio Output Mode	None (or) Not Applicable
Battery Average Life	80 Hours
Mount Type	Wrist Mount
Resolution	480 x 272
Compatible with Vehicle Type	Bicycle
Screen Size	1.3 Inches
Additional Features	PacePro™ Feature; Grade-Adjusted Pace; VO2 Max; Performance Condition; Sync Training Plans; Built-in Sports Apps; Visual Race Predictor; Track Running; Targeted Adaptive Coaching for Cycling, Race Adaptive Training Plans; Daily Suggested Workouts; Garmin Coach; Triathlon and Multisport Profiles; Wrist-Based Running Dynamics; Wrist-Based Running Power; Endurance Score; Real-Time Stamina
Connectivity Technology	Bluetooth, USB
Map Types	North America
Item Weight	1.9 Ounces
Item Dimensions L x W x H	1.8"L x 1.8"W x 0.6"H

Garmin 010-02638-10 Forerunner® 955, GPS Running Smartwatch, Tailored to Triathletes, Long-Lasting Battery, Black

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