Zero Anaerobic Effect After Hard Run

How does Garmin calculate Anaerobic effect exactly? I have been using my Fenix 5 for a good few months now, so it?s dialling in to my training nicely now. It?s got to the point that I am starting to really rely on the data it provides me. I have also started to use the HRM run too and that is starting to give me more good data. Yesterday, however, I did a hard run in atrocious weather where I was in my maximum HR zone for a good 3 Miles. When I finished my run I got an Anaerobic effort of zero.

Does anybody know what this may be the case. As I said my HR was in max for a good 20 mins.
i did lose GPS for a short period which gave me bad data but I wouldn?t have thought Anaerobic data would require GPS data to calculate.

0 mjsol over 7 years ago

PS. On topic.

Your info on Anarobic rating was helpful. Thank you. I do Body Combat, But I'm guessing my heart rate doesn't vary enough in that workout to score higher in that category? It's the variability that intervals and sprints produce that triggers that score?

0 HermanB over 7 years ago

Herman B,
Do you have an explanation of the Fitness Level anywhere? Does Firstbeat do the algorithms for the lower level garmins as well? It seems my Fenix 5s needs consistent gps (outside workouts) to measure Fitness Level? But a Vivosmart 3 can measure Vo2 max WITHOUT gps?

What gives?

My beef is that my watch has rated me 79 years OR OLDER since the beginning. I guess because I don't workout outside enough. I'm a gym rat. It can't get my VO2 Max.

Hopefully I don't get flagged for off-topic conversation, but quickly.

Yes, all automatic VO2max detection capabilities onboard Garmin devices are produced by the Firstbeat analytics engine onboard the device. While there is a tremendous amount of stuff going on behind the scenes to provide the calculation - it's a 'smart algorithm,' meaning that it is designed to identify which incoming data is suitable for analysis - the two key inputs for the calculation during running/walking activities are movement speed and HR (as a percentage of max). And of course the accuracy of those elements DO influence the accuracy of the results.

Movement speed can be either from GPS (Fenix 5 outdoors in your example) or from accelerometer data (V?vosmart 3 in your example).

Here's a quick intro from our website.
https://www.firstbeat.com/en/consumer-feature/vo2max-fitness-level/

My beef is that my watch has rated me 79 years OR OLDER since the beginning. I guess because I don't workout outside enough. I'm a gym rat. It can't get my VO2 Max.

The good news is that it doesn't take a lot o[HTML][/HTML]f running (only about 10mins or so) to update, which is pretty doable for most folks, provided the info is important for you (protip: if your VO2max is way off, then it's going to impact the rest of your feedback from things like Ae/An Training Effect, Training Status, etc.

PS. On topic.

Your info on Anarobic rating was helpful. Thank you. I do Body Combat, But I'm guessing my heart rate doesn't vary enough in that workout to score higher in that category? It's the variability that intervals and sprints produce that triggers that score?

Yea! On topic! In short, yes. Those episodes where your HR is climbing quickly to catch up in support of the workload you've introduced are key to eliciting an Anaerobic TE score. That said, combat training for things like boxing, etc. ought to produce those in spades.

0 SteveCRunner over 7 years ago

Here is a workout I did today and got 5.0 for both TE's

I am 60 years old so my MHR is 160.

That doesn't follow at all. You are getting misleading results. 220-age is only a first guess and your true value likely lies in the range140 to 180. You need to do a test to find your true max. Until then your TEs could be way out.

0 Former Member over 7 years ago

That doesn't follow at all. You are getting misleading results. 220-age is only a first guess and your true value likely lies in the range140 to 180. You need to do a test to find your true max. Until then your TEs could be way out.

I had 2 stress tests done in the past 3 years and both showed my MHR at within a few BPM of the 220 - age formula, so I guess I am one of the people that can go by that formula.

I will add that it was only the second workout using the device, so maybe its still learning my metrics.

It also gave me an initial VO2 max of 24 which is not correct either.

0 slothslayer over 1 year ago in reply to HermanB

Sorry for slightly off topic as I own a Forerunner 265 and not a Fenix but I found my way here via google and was hoping to learn why I'm getting zero anaerobic benefit from a wide variety of runs as well as gym workouts including activities like Russian Twists, Mountain Climbers and Burpees. My shiny new fitness friend insists my training routine is next to useless despite having inspired me to work harder this past month than I have in 2 years lol. Beginning to feel a bit discouraging as I don't know how to satisfy the algorithm beyond maybe sprinting straight up the nearest hill I can find a few dozen times

Thanks!

0 Etupes25 over 1 year ago in reply to slothslayer

The first thing to check is your HR Max value. If your doctor lets you, go do these sprint uphills as fast as you can but at steady pace, walk back down. After interval 6 you should be struggling to keep the same pace as the first interval. After you complete the last interval possible, you should be about 2-3 bpm off your HR Max. Alternatively, run the fastest 5k you can, at steady pace and add 5bpm to your final HR. Or find an HR Max test on the web...

Anaerobic intervals should be completed at steady pace/power. If you run 6 to 8 intervals at your maximal steady pace for some interval typically between 45s and 90s max, and you walk about 3mn between each interval, you should get an anaerobic workout. If you don't, you could have run faster or your HR, pace or HR Max data is off, and it will take a few weeks on flat terrain running, balanced training to correct.

Other activities, unlike running and biking, don't have a work output metric like pace or power to correctly identify powerful short intervals while the HR is still rising up. So they rely only on the HR and HRV rate of change and mouvement to identify anaerobic vs rest efforts. This is hard to accomplish at the gym. You would need to perform exercises that rise your HR very fast, keep it at least at 80% to 95% of your HR Max for about 90s to 45s respectively and approximately, then stopping for about 3mn. About 6 to 8 intense, explosive 1mn rounds at full speed like box jumps, lunge jumps, burpees etc might get you there, but it is very hard.

0 slothslayer over 1 year ago in reply to Etupes25

Thank you very much Etupe!

This is very helpful and good to know.

While the Garmin training program I've been following since getting my new watch has had me doing some activities that resemble the form of HIIT you're describing, they don't quite hit the full duration and intensity you've described here. I'll make a point of adding in 8 intervals at a minimum of 60 seconds of sprinting in the weeks ahead and see what kind of data the watch returns.

In the meantime, I'll rest easy knowing that my gym routines aren't quite as useless as the watch has been suggesting and carry on with a bit more confidence and assurance = )

0 SteveI 9 months ago

Strangely, I ran anaerobic workout, with intervals, on a treadmill yesterday far faster than the recommended speed and it gave me 1.0 for a score. Today, I thought F'it and ran outside for 3 miles, first mile easy, then final 2 miles as hard as I could. Almost 10 minutes in zone 5. My watch gave me an anaerobic score of 1.8. My anaerobic attempts have been poor, so I will take 1.8 every time.

0 Etupes25 9 months ago in reply to SteveI

SteveI said:
Today, I thought F'it and ran outside for 3 miles, first mile easy, then final 2 miles as hard as I could. Almost 10 minutes in zone 5.

It is a common misconception that getting the heart rate in zone 5 denotes an anaerobic effort. You can get your heart rate in zone 5 by running long enough at threshold, and it is still a mostly aerobic effort.

To get anaerobic effort with the watch, you need to run maximal *steady* effort for a duration of 40s to 1:20mn and then repeat. For example:

- run maximal steady speed for 1mn

- walk for 2mn

- repeat 8 times.

E.g I get up to 3.5 anaerobic TE when I do 8 400m repeats maximal speed with 90s rest periods. I couldn't do a 9th repeat...

Also, you need to make sure:

- your HR Max is correct. If your doctor lets you, and your are a trained runner, take your 5k personal best, add 5bpm to the peak HR. This will be very close to your HR Max,

- use a reliable source for HR. Use a cheststrap

- you use a reliable source for pace. Use a foot pod for treadmill or the HRM-Pro chest strap. Pace (or power for cycling) is very important for proper anaerobic evaluation.

0 SteveI 9 months ago in reply to Etupes25

@Etupes25.

Thx.. The reason for my post is that I got more anaerobic benefit accidentally (TE 1.8), than when I was trying to do an anaerobic activity. For the activity you mentioned, garmin tells me to run 8.3/mi. If I do that I get TE 0. 7-7.5/mi gets me TE 1. I'm guessing the treadmill may be part of the issue. It takes a few seconds to get up to speed. I'll try the same outside on a track when the weather permits. Decades ago, we called them windsprints.... (I hate windsprints.)

update: i meant garmin recomended 8:30/mi and I ran 7:00-7:30 /mi. New anaerobic recommendation is 7 x1min @ 8:10/mi. I'm guessing I will have to run @ 6:40/mi (9mph) for it to register a score.