Should I train today? How to decide? using Firstbeat + Sporttracks + BIOFORCEHRV Garmin 920XT

This morning, when faced with the decision of “Should I train? or not” I have several bits of kit that tell me different things. Being a grown-up I don’t listen to them slavishly but I DO take into account the information I am being presented with.

Here are some thoughts:

1. After yesterday’s session my Garmin 920XT told me that my recovery time was 72 hours…eesh Saturday ! Well, firstly, that only means how long to wait until the next HARD session (VO2). So I CAN still train today, just easily/aerobically.

2. The Garmin device also shows RECOVERY HEART RATE too immediately after yesterday’s session. You have to wait 2 minutes for it to be calculated before pressing ‘SAVE’. Also true on 910 and other models. That info is put in a FIT file and so the likes of sporttracks pick it up. Here it is


Well, to be honest, I don’t know what to do with that info 🙂 Maybe someone will let me know. It is surely VERY dependent on when you precisely STOP the session. So, I ignore this.

3. In sporttracks I import my data and prefer to use that rather than Garmin Connect (which is now pretty good – but wasn’t years ago). And then in Sporttracks I use the TRAININGLOAD plugin. I’ve used this for years and it is VERY useful. It shows me a very complex graph. I’ll just explain the pertinent parts that are circled below


The vertical red line is today.

The red graph reflects my tiredness from all that training. So I’ve been on a downwards cycle for the last few months BUT I’ve been ramping it up over the last few days. This shows my entire TRIATHLON tiredness (I can also view it by discipline should I so wish). So this would tell me that I’ve been more tired historically (cumulatively at the time). Might be a time for a little rest or maybe I could do a little more. Inconclusive.

As the green line approaches zero it shows less readiness to train. It’s currently at 2. (See the circled box at the bottom). This to me indicates that I can still train. It could be much lower.

4. I could trust my coach and do what s/he says I should do today and/or give him/her all this info. Personally I think you SHOULD do that. I’m not on a particular plan at present though. Free training !

5. Then I use a waking HRV test every day by BIOFORCE. Garmin or Sporttracks need to incororate this info in their product offerings. But they don’t. Roll-on Connect IQ apps. Here is what the excellent BIOFORCE shows. (Also consider Elite HRV and ithlete which have additional functionality)


I won’t go into this too much right now. But it says I’m good to train. Although I have had a chequered past over the last week or so. (Which agrees to the falling green line and rising red line in Sporttracks – as it should). The Garmin RECOVERY TIME of 72 hours also takes into account the hangover from recent hard training. I often use BIOFORCE as my guide for any particular day – based on this I would NORMALLY train.

6. I have also been looking at FIRSTBEAT ATHLETE quite a bit. It has a COACHING FEATURE that is inbuilt and tells you what sort of future training loads you should put yourself under. I understand it uses Training Effect (TE) and EPOC calculations and is based partly on HRV data from my Garmin. FYI: Firstbeat produce some of the recovery calculations used by Garmin.


This is pretty clear. REST. But work hard tomorrow and VERY hard the next day. Kinda what I’d planned. Good.

Note IT plans the future load or me I don’t put that into the ATHLETE software.

You can see from the graph that I have circled my current load. It’s well within the grey limits of acceptable training range based on my fitness and number of weekly training hours. And yes it knows I have been slacking 🙂 Christmas…c’mon give me a break !

FIRSTBEAT ATHLETE does not take into account my swimming load as I currently cannot easily get HRV HR data into ATHLETE. So it is missing a vital component of my training load. So I cannot trust it totally. Then again, it is saying REST based on my cycling and running – so swimming would make it more likely to say rest.

7. How do I intuitively FEEL ?

I feel a bit tired. I could quite easily go for a run. It would probably have to be a Z2. My bike legs for sure need a rest. I could quite easily feel like a rest as well.

8. Start a session anyway?

A great feature of the 920XT and, from memory, the 620 & Fenix2 is the message that pops up 12 or so minutes into a session telling you how your recovery is. Similar to the Bioforce waking HRV I imagine. However once you’ve already started a session you will most likely either finish it or tone it down a bit. So this is useful info. But training when it suggests otherwise might impact recovery benefits.

ANSWER: So what did I do? Well I had an evening swim. Well I’m going to have one later. Relatively short session. I listened to all the above markers and made my call. If you train more than 5 days a week, say more than 6/7 hours a week then I think you need some tools long these lines if you want to get better a little more smartly. The reason being that we improve/adapt as we rest from exercise – not AS WE DO IT. So training more and more STOP the improvement. We need to rest. These tools help us decide WHEN to REST.

You will rarely need more than one day of complete rest. You will usually need two clear days between hard sessions (which can include activity).

There you go. You could just use that last paragraph/sentence to guide you. It’s a good rule of thumb.

What do you do?

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6 thoughts on “Should I train today? How to decide? using Firstbeat + Sporttracks + BIOFORCEHRV Garmin 920XT

  1. Hello the5krunner,
    I was just wondering: how did you calculate, in sport tracks, the HR Recovery Decrease calculated field, what’s the formula?


    1. hi, yes I had seen the white paper thank you. I had the same query as you.

      TR from wrote to me on 9Jan 2015: “Both EPOC/TE and daily performance calculation does utilize HRV, but not in a same way as when analyzing e.g. night time recovery. EPOC/TE can be estimated also without HRV, but HRV brings more accuracy to the analysis. With HRV we can for example utilize respiration rate information when analyzing the EPOC/TE.”

  2. Great article, thanks for it.

    I also use ST with Training Load, its very good to analyze my training and change it if its necessary… but I have a question: do you have any idea what is the formula to calculate recovery time? Unfortunately my watch cant estimate it (just a FR210).

    1. no sorry. I think it comes from research from Bannister in the 1960s
      ask the developer mechgt or try the sporttracks forum.
      to be honest I don’t think you will get the right answer. whatever answer is given to you will not be specific to you over a variety of factors
      as you may have realised by reading the above post. the answer may well lie in waking HRV. the apps are free – elite hrv, ithelte, bioforce (or very cheap). all you need is a Bluetooth HRM. this WILL tell you if you are ready for a hard session over the coming day after you have done the reading – I used to do it that way for years…it works. I now have QS EMFIT but that is quite expensive and I don’t train as hard these days so it’s an easier call for me

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