Fitness & Freshness (Summit)

Fitness & Freshness helps track your levels of fitness, fatigue, and form over time. The Fitness & Freshness chart is currently only available to power meter or heart rate users with a Summit membership. Any activities recorded with heart rate data are included in your Fitness and Freshness calculations.

How Fitness & Freshness is Calculated

While fitness is a complicated concept, it can be simplified to just an accumulation of training. While this type of fitness and freshness chart is popular among endurance athletes it can be difficult to understand at first. In general, the overall numbers aren't as important as general trends. If possible, it's best to compare where you are now to times in the past when you were fit. This can help you determine your current fitness and how to get even better.

  • The Fitness Score is calculated using Training Load and/or Relative Effort, to measure your daily training, and an impulse-response model to quantify its effect over time. This will intuitively capture the building up of fitness, as well as the loss of fitness during a break.
  • The Fitness & Freshness chart uses Training Load and/or Relative Effort to quantify your daily training. Training Load is calculated using power data and Relative Effort is calculated using heart rate data, so you'll need a power meter or heart rate monitor to take advantage of this feature.
  • For Summit members with no power data available, we generate the chart using only Relative Effort. For those who have at least 10 rides with both Relative Effort and Training Load, the athlete-specific best-fit between the two is calculated and used to fill in Training Load for rides with heart rate but not power.

Viewing your Fitness & Freshness Graph

Hover over the Training tab at the top of any Strava page, then select Fitness & Freshness from the drop-down menu - or simply visit this page, you will be able to view and interact with your Fitness and Freshness curve.

  • You can select the range of time represented by the graph, as well as enable plotlines to track your Fatigue and Form (more on those later).
  • Clicking on any point in the graph will 'focus' on that time interval - and show your specific Fitness, Fatigue, and Form values at that date.
  • Below the graph, you'll see the relevant activities that contributed to your Fitness values, as well as their Training Impulse. Simply click again anywhere in the chart to 'unfocus.'
  • Races are marked in red to help you analyze fitness over longer chunks of time. The fitness delta next to the fitness score will show how your fitness has changed over the last seven days.

A bit more information...

Our method for calculating Fitness, Fatigue, and Form is based off an impulse-response model first developed by Dr. Eric W. Banister in 1975. It was later applied to cycling by Dr. Andy Coggan. The concepts apply to any measure of training stress. For example, the first models used average heart rate and time. We use Training Load, computed using power data collected with a dedicated power meter.

  • Conceptually, fatigue is easy to understand; it's that tired feeling which limits your performance. We model it the same way as fitness, but on a shorter timescale. You'll notice the score go up quickly after a couple hard days, but also go down quickly as you take a few days off.
  • Being in form, or "peaking," happens when one is very fit but not fatigued. Here we model this as the difference between your Fitness Score and your Fatigue Score.

For more information, please visit our training glossary.

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  • Great to see running added to the F&F graph, but.... how is the running score calculated? It seems it is based on suffer scores which are based on HR zones. I use HR zones for both bike and run, but my training zones are different (I don't have a PM). I customised the zones for the bike (lower HR), but this results in my run suffer score being inaccurate. As an example, a 30min easy run had a suffer score nearly twice as big as a 1 hour interval bike session. The result.... the F&F graph is giving me false information.
    Is there a way to have separate running and bike HR zones customised (like Garmin and others do)? Or can the run suffer scores be calculated by Pace Zones? Thanks.

  • One thing I notice - especially now that it shows Running (my primary activity) - is that with a running fitness of 86 'fitness' which is a fairly long term metric drops like very quickly...even with sustained training- is a 3-5mile 'easy' or 'recovery' run (suffer 30-55) . No way with 35-50miles per week... that a 5 mile aerobic run would allow my fitness to DROP.... I can understand a recovery run (3-4mi) isn't going to help my fitness increase much (or at all) - but I don't see my fitness level dropping as if it was a rest day. Same with one single rest level holds steady (if not increases) with one rest day or easy aerobic activity. (not dropping 3pts in one day of rest...) Eventually dropping without a solid 'training stress'.

    Monday Rest day dropped fitness 3points...then todays 7.1mile 'easy' run just held it steady. I guess it definitely shows the benefits of Tempo and Intervals. But also very much discounting the benefits of '80/20' training...'most easy...some hard'...and 'base' training that has shown to be very helpful for races over a couple miles.

    ALSO: Just noticed that the Suffer displayed on the little bar graph at the bottom, are not correct!?!?! Says SufferScore: 55 for one of them when I hover over the activity - but when I click on the activity it says 42.

  • I had mentioned that the Suffer Score rating on the F&F graph page doesn't match the actual workout Suffer Score in one of the activities....

    Well dug into it a bit further - and it doesn't match for ANY of my activities. Is the suffer score on the graph using the 'default' HR zones where the activity page is using my 'custom' zones? I have found the default zones don't seem to jive with what is typically accepted as proper 'Tempo' or 'Threshold' workouts for Running (too low, into what is generally accepted as 'middle-higher aerobic (greyzone)). So i have them adjusted for that....

  • When do you make it availabe in the Strava App?

  • This potentially very useful graph is rendered almost useless by the lack of ability to manually enter an estimate of average heart rate to calculate the training impulse when you do not have an average heart rate eg garmin strap does not work properly, you forget your garmin and use the app on your phone, or you forget your strap etc etc. Just one session lost can seriously mess up the graph for months! Training peaks allows you to do this and I assumed that you would also but no - making me regret from changing from training peaks - and with the latest update you STILL can't do it (I don't think!) despite it being asked for in these posts two years ago! Really poor as it cant be hard to do!

  • Is there a page anywhere that actually explains EXACTLY how Strava calculate the fitness and fatigue scores, as in: an actual equation. I had assumed it was simply the average training impulse over "X" number of days, except I've tried every number for "X" and I can't replicate the results.... (Yes, I'm an engineer and maths geek and I don't like the simple answer "More riding = Higher Fitness score").

  • Strava is one of the few sites that doesn't let you define separate heart rate zones for cycling and running, which are quite different. That means you can only set heart rate for one or the other, and the one you didn't set it for is going to have a suffer score that's way off. Totally pointless. It's unbelievable Strava hasn't implemented this basic feature yet.

  • I've noticed that Strava massively over-calculates "Training Impulse" if you do multiple activities in a day - you can do 2 very short & low effort activities one day which will have a massively greater combined training impulse than a much longer (in total) and higher effort single activity another day - which means the whole Fitness & Freshness graph is pretty useless - if like me you record the occasional dog walk alongside bike rides and also often do ~16 rides in a day when doing MTB uplift days...

  • I would love to see how my fitness and freshness score compares to others my age. I have spent the last 6 months training for a 50k trail run and have seen my fitness number increase from 45 to currently 80. It would be very helpful for me to see where I stand.

  • This has stopped working for me for over two weeks. I am a premium member, how can I get it reinstated?

  • I'm premium member but fitness and freshness are not calculating any more. It shows zero all the time. I'm on internet Explorer (Windows 10).

    I put question on help desk but no one cares.

    Training peaks anyone?

  • Kristian/John - are you guys using a heart rate monitor and getting Suffer Scores for each of your activities during that time frame?

  • Is there any future enhancements that will take into consideration the training effects from other activities like swimming and surfing? I don't plan to wear a HR monitor in the water when trying to catch overhead waves but I do know I exit the water completely exhausted and there's got to be a "fitness & freshness" bump from these activities.

  • Totally agree with a couple of posts here. This feature is nice but a) really would like to know the actual algorithm (I can't replicate it with just a 6 week CTL (weekly ATL averaging) which I think is what Coggan intended although I think I can probably reverse engineer it if I try hard enough (can at least say what period your "fitness"/CTL averages over??), and b) really want to be able to manually input training load for sessions with missing HRM/PM data as otherwise the graph does get screwed up for weeks/months when I forget to turn my app on.

  • Did anyone else's "Fitness" suddenly decline since the beginning of April, despite training seriously?

    Runalyze shows my fitness increasing very well.

  • Why is the graph a flat line for everything but the power meter only? When i click on power meter + Heart rate, it only gives me a point on a flat line but no history of where I have improved from. I have to click on power meter only to get any useable data...

  • "While fitness is a complicated concept, it can be simplified to just an accumulation of training." - If true, then base this info off of the accumulation of activities and res periods, not the heart rate data. I don't ride mountain bikes with a heart rate monitor, so the data is meaningless.

  • I recently did a 102 mile ride but found out afterwards that my heart rate monitor wasn't working, so it appears none of this ride will be factored in to my "Fitness and Freshness" score?

  • Brian - why are you complaining to Strava about this? Fix your HR monitor. How could they possibly add this to your score without HR or power data? You do realize two people can do the same ride at the same speed and have drastically different physiological responses right? Strava sucks on a lot of issues but this is not their problem.

  • Yeah things like this happen which is why Strava really needs a way to enter training load manually otherwise you're essentially screwing up the calculation for the next 6 weeks!

    Tip; If I lose power & HRM like this, I've taken to downloading the .gpx from a similar ride, editing the date with find/replace in Notepad, and reuploading it - setting it as private so the mileage isn't including in challenges, clubs. etc. This is a really silly workaround when if I could just type a training load estimate into Strava directly it would save the effort and be much less messy.

  • Brian Hamman,

    things like that happen often I suppose. don't bring it with on a vacation that you end up running/biking a lot, sensor dies and you don't get a new strap right away, etc.... sure would be nice if it allowed for a training load calculation based on time/distance/elevation.... similar to how it does the Estimated Power.

    For instance for me running.... I have pace zones setup. So if I run 10 miles mostly in the Tempo pace... easy enough to know that would be a solid Suffer score. If I do 3miles in Zone1....low. Neither are it's handled now.

    If (HRM=Null) then
    Calc Estimated Training Load (Time,Distance,Elev,Power-PaceZones)

  • These are great solutions unfortunately Strava has known about this issue and refuses to fix it, just like all of their other problems with segments, searching, etc.

  • Thanks, Richard and Nick, glad at least you two understood my question. It should be easy for Strava to add an option for one to manually enter an average heart rate if needed.

  • Hi Strava Support, on my fitness curve the data was in 2 digits ex. 57, now its suddenly changed to 3 digits 140 ?, why ?

  • Per, I've created a support ticket so that we can look into your question.

    Regarding the ability to manually account for a fitness and freshness value: we will do our best to make this happen for you. Thanks for the feedback.

  • Hi Elle, That would be fantastic if you could make it possible for us to manually add an average heart rate to account for a fitness and freshness value...good luck! Thanks, Brian

  • I can please request colour-coded graphs for fitness, form and fatigue?
    Lines are not easy to follow when they're shades of grey.

  • Elle,

    After many month marathon training build up...and afterwards many 2-10hr bike rides.... I have noticed that my normal morning 'easy' 6-7mi run at even faster pace then this spring... gives me a very low suffer score (due to very low HR). Result is my "Running Fitness" continues to drop.... I am still getting in 20-40miles a week, but now that my HR is lower, my Suffer Score is lower, gradually lowering my "Fitness"...

    I know that is tricky to account for, "doing more work on a run NOW....but with a lower HR then 6months ago", I know I should just speed up to maintain a similar Suffer Score... but often I am with training partners. I would think that using the GAP pace zones that are setup and calculated... it could definitely help with it. Pretty much use the GAP pace in a similar way as Power Meter data for bikers? Or use it to adjust the 'training stress' on your end?

    I guess I could drastically overdress on cool make sure I get a higher heart rate... or more hang-over runs :-)  lol


  • Is there a way to view past fitness and freshness data in a more detailed view than just viewing "all time"? Perhaps I'm missing something simple. My history goes back nearly ten years and when viewing my fitness data on that kind of timeline, the data is too compressed to see any detail.

  • Why when I update my FTP do all past values in the fitness profile shift? That makes no sense. My FTP in the past has not changed - just now and in the near future.

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