Tracking Heart Rate

yea it's well known wrist heart rate doesn't work that well for strength due to the wrist always flexing etc.

what i use more is the stopwatch to time intervals and which i now find irritating to use ... as garmin has done a change recently and thinks they're being smart by making it switch back to the watch face after 5mins in an effort to "improve battery life".

I recommend the Scosche arm band. Works well with Garmin and much more comfortable than a chest strap.

The Wahoo TICKR works fine with this watch. I have it broadcast to both my edge 520 and the vivoactive3 with no problems.

I really wanted the TICKR-X to work for me, but I found that some strength training movements and while rock climbing the strap would separate at the point of connection with the device. Due to how the device is designed, the monitor connects the two sides of the strap with a snap. At first glance the snap seems strong enough to withstand various chest movements but it unsnaps quite easily. When it would unsnap it would cause me to have to stop and reconnect and it was a pain. I ended up going with a Polar H10 and have liked how it works with my apple and android devices as well as my watch. Just my experience, otherwise I thought the TICKR was great.

I've been using the simple Garmin heartrate strap with my Edge 520 and it works great. I have not tried to link it to my VA3 but I presume it would work. I find the chest strap is far more accurate (I'm seeing it on my Edge 520 while looking at HR on the VA3). You can purchase it cheap on Amazon at: https://www.amazon.com/gp/product/B000UOD5QM/ref=oh_aui_detailpage_o08_s00?ie=UTF8&psc=1

I've been using the simple Garmin heartrate strap with my Edge 520 and it works great. I have not tried to link it to my VA3 but I presume it would work. I find the chest strap is far more accurate (I'm seeing it on my Edge 520 while looking at HR on the VA3). You can purchase it cheap on Amazon at: https://www.amazon.com/gp/product/B000UOD5QM/ref=oh_aui_detailpage_o08_s00?ie=UTF8&psc=1

I was using that monitor with my Edge 520 and it works fine but not so with the VA3. It kept dropping and reconnecting with the VA3. I bought the TICKR and that one works great with both the 520 and the VA3.

I also have a VA3 and used wrist HRM for weight training for ~6 months. Now I use "Garmin Premium Heart Rate Monitor (Soft Strap)" HRM for ~2 months.

In general it is more accurate also for weight training as the external sensor reacts much faster than the wrist HRM. For example with external you see how your HR goes up to 130 and then down to 80 a few secs later. With wrist it slowly goes up from 80 to 100 and stays a little bit longer on 100. The biggest improvement is for workouts where your hand is above your heart (squats with barbell, crunches etc). Here the wrist HRM shows a HR which is much too low.

I'm happy with the Garmin external HRM (you can remove the electronical sensor and put it in the shower/washing mashine etc.). But I don't have any experience with any other external sensors.

The Wahoo TICKR works fine with this watch. I have it broadcast to both my edge 520 and the vivoactive3 with no problems.

+1 for the Wahoo Tickr HRM. I've mine for over 2 years and a half and although I have put over a thousand hours on it, I only changed the battery twice and still on the same strap. Accuracy is still also very good.