“Trainjng effect” not effective for endurance

Anyone trying to make sense of the Trainjng Effect Garmin connect spits out at the end of a workout?

My understanding of heart rate training for endurance running is centred around zone 2 (60-70% of HRR) and the 80/20 philosophy. That being, spend 20% of your training in high zones (4-5) and the remaining 80% of your training in zone 2. While zone 3 is a bit of a grey zone where you’re working too hard for the aerobic system to realise maximum adaptations and too low intensity to get maximum anaerobic benefits. So better bang for buck spending time either in zone 2 or zone 4 (with some exceptions I realise zone 3 has a place).

This is is where Garmins “Training Effect” makes me scratch my head. After completing a 45min run in zone 2 I get an aerobic score of 2.8 (maintaining aerobic fitness).
But when I did a run 43min in zone 3 I get an aerobic score of 3.8 (improving aerobic fitness).

Also the gauge for the heart rate scale on the watch specifys zone 1 warm up. 2- easy. 3- AEROBIC 4- threshold and 5- maximum
Why would zone 3 (70-80%HRR) be aerobic??

Can gurus shed shed light on this one?
  • Not a guru. Just a sub par runner. But I have had exactly the same experience as you, and if you browse around in these forums, you will find others with the same experience.

    To your specific examples, I would note that you should probably increase your duration when training in Zone 2 to get the full benefit from polarized training. But even if you do that, you will probably find that even if you double the duration of your Zone 2 run, it will still not give the same aerobic score as your Zone 3 run.

    I think we can just conclude that Training Effect doesn't really do well with polarized training.

    Personally, I use Active Calories to keep track of my training load. I find that my total weekly Active Calories count has a better correlation to my perceived weekly training load. But it feels like a bit of a joke that I have to use a tool which was not really meant for this purpose.
  • For me it works perfectly. If you are training for aerobic training effect you want to train at a more or less constant pace in the top of Zone 4 as close to your lactic acid threshlod as posible (if you are using your LTHR for setting your heart rates zones, this will be what separates zone 4 from 5. For example see bellow image, for reference I'm a 46yr old average runner and my LTHR is at 176bpm. This is for 30-45min sessions, the longer your run is the lower that average HR can be to achieve the same effect.

    (If what you want is an anaerobic training effect improvement, then you want to do HIIT trying to go as low as posible in the recovery phase of the cycle and then as close to your maxHR as possible on your peaks)

    ciq.forums.garmin.com/.../1412215.jpg
  • It's worth noting that the body responds fairly slowly to aerobic training in terms of physiological changes and increased fitness. To be effective, you need to do a fair bit of it over an extended period. The upside is that once built, the benefits of aerobic fitness are persistent, and can be maintained fairly easily. More intense workouts will generate a faster response in terms of increased fitness, but the benefit they create is harder to sustain. The TE scores generated roughly reflect the impact of that workout on your aerobic fitness. The 2.6-2.8 from a zone 2 workout reflects the fact that individual workout may not have had a huge effect, but rather that you build it through high volumes of zone 2 over time. The higher TE's of more intense workouts reflect the greater contribution of THAT particular workout.

    Zone 2 efforts really build aerobic efficiency and economy. More intense VO2Max workouts also have an aerobic effect, as they increase maximum oxygen uptake, even if they are not efficient. Combining the two in a training program (such as your 80/20 rule) allows you to make better use of an increased capacity, which makes you MUCH faster.

    Zone 3 is not a "bad" zone, but it is generally regarded as not being the most efficient in terms of the recovery time it generates.

    If you want to understand more about Training Effect, it is worth reading Firstbeat's (they provide the algorithms in the watch) White Paper on the subject. https://www.firstbeat.com/en/training-effect-firstbeat-white-paper-2/
  • If you are training for aerobic training effect you want to train at a more or less constant pace in the top of Zone 4 as close to your lactic acid threshlod as posible

    No, you need some work in that zone. But it has been proven over and over again that you also need a lot of work (actually most of your training volume) around your aerobic threshold. For most people, this threshold is at a considerably lower heart rate than your lactate threshold / anaerobic threshold.

    Read up on Stephen Seiler who was the pioneer in scientifically proving what a lot of running coaches already knew from trial and error.

    Edit: I don't usually put it so simplistic and simple-minded as I did above, because there are certainly a lot of nuances to the topic. But I became provoked about the similarly simplistic and simple-minded approach of doing all your training at lactate threshold.
  • No, you need some work in that zone. But it has been proven over and over again that you also need a lot of work (actually most of your training volume) around your aerobic threshold. For most people, this threshold is at a considerably lower heart rate than your lactate threshold / anaerobic threshold.

    Read up on Stephen Seiler who was the pioneer in scientifically proving what a lot of running coaches already knew from trial and error.

    Edit: I don't usually put it so simplistic and simple-minded as I did above, because there are certainly a lot of nuances to the topic. But I became provoked about the similarly simplistic and simple-minded approach of doing all your training at lactate threshold.


    No, you didn't understand my post, I didn't say you have to train like that always, I wasn't talking on how you need to train, nobody is saying you don't also need lower intensity and longer duration sessions in Zone 2 (which will give a lower training effect and that is ok, its intended like that) and so on, I was just illustrating what type of training corresponds to a higher training effect in Garmin Connect (in both aerobic effect and anaerobic) which is what the poster of the thread was wondering, and imo its fairly simple to explain and understand, refer to the First Beats white paper on training effect posted by mcalista.
  • 966, this thread is about low intensity work not being "rewarded" enough. It is not a thread about which kinds of high intensity work gets rewarded most.

    The problem is that a lot of low intensity work is needed for getting optimal aerobic fitness, and when you do this kind of training, your Garmin watch will tell you that you are slacking off, which is obviously not the case.

  • 966, this thread is about low intensity work not being "rewarded" enough. It is not a thread about which kinds of high intensity work gets rewarded most.

    The problem is that a lot of low intensity work is needed for getting optimal aerobic fitness, and when you do this kind of training, your Garmin watch will tell you that you are slacking off, which is obviously not the case.



    I think you are misintepreting what the training effect tells you, getting a 2.x training effect from an easy zone 2 workout is not telling you you are slacking off, its telling the effect of that particular session, not on the long run, nor the cumulative effect of a 80/20 split. You have to combine it with the training load data and status, vo2max, etc. A zone 2 workout cannot give you a 3+ or 4 training effect because then it would be useless as a higher intensity workout would give you the same short term training effect, and it doesn't. As mcalista also mentioned, the training effect measures the impact of that session only. Like I said, read the white paper, its all explained.
  • 966, this thread is about low intensity work not being "rewarded" enough. It is not a thread about which kinds of high intensity work gets rewarded most.

    The problem is that a lot of low intensity work is needed for getting optimal aerobic fitness, and when you do this kind of training, your Garmin watch will tell you that you are slacking off, which is obviously not the case.



    While there are indeed some issues with using EPOC for Training Load at lower intensities, the EPOC based Training Effect (which is the subject of this thread) is useful. TE is not just "more is better", and thinking that a TE of 2.6-2.8 is "slacking off" is misinterpreting the TE metric.
  • Same problem here... I did a 17 miles run yesterday (HR~150), a 5 miles speed run (HR ~175) the day before. My watch calculated that I actually didn't need any rest (13 hours light training) after that, status "maintaining"... my body has a different oppinion though. Those longjogs never seem to be appreciated the way it should be.
  • Former Member
    0 Former Member over 6 years ago
    It's worth noting that the body responds fairly slowly to aerobic training in terms of physiological changes and increased fitness. To be effective, you need to do a fair bit of it over an extended period. The upside is that once built, the benefits of aerobic fitness are persistent, and can be maintained fairly easily. More intense workouts will generate a faster response in terms of increased fitness, but the benefit they create is harder to sustain. The TE scores generated roughly reflect the impact of that workout on your aerobic fitness. The 2.6-2.8 from a zone 2 workout reflects the fact that individual ">mybkexperience">mybkexperience workout may not have had a huge effect, but rather that you build it through high volumes of zone 2 over time. The higher TE's of more intense workouts reflect the greater contribution of THAT particular workout.

    Zone 2 efforts really build aerobic efficiency and economy. More intense VO2Max workouts also have an aerobic effect, as they increase maximum oxygen uptake, even if they are not efficient. Combining the two in a training program (such as your 80/20 rule) allows you to make better use of an increased capacity, which makes you MUCH faster.