tag:blogger.com,1999:blog-1564958057737541664.post6020348141205371643..comments2024-02-14T17:11:22.168-08:00Comments on On Bicycles, and.... what else is there?: Strava Suffer Score decodeddjconnelhttp://www.blogger.com/profile/01484858820878605035noreply@blogger.comBlogger40125tag:blogger.com,1999:blog-1564958057737541664.post-28471531518119107562016-07-28T17:00:38.338-07:002016-07-28T17:00:38.338-07:00I think i might have worked it out for running:
Z...I think i might have worked it out for running:<br /><br />Zone 1 - 30<br />Zone 2 - 60<br />Zone 3 - 120<br />Zone 4 - 240<br />Zone 5 - 480<br /><br />Let me know if you think its right!Aaronhttps://www.blogger.com/profile/05628899367355225527noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-61535120433415335402015-11-25T12:26:36.717-08:002015-11-25T12:26:36.717-08:00Dan,
Sorry to come so late to this conversation, ...Dan,<br /><br />Sorry to come so late to this conversation, but I just noticed that my Strava suffer scores for long rides seem way higher than other riders I know on similar rides, and in searching for info, I found your blog.<br /><br />My first thought about your analysis is that since heart rate is being averaged into five groups, the algorithm sure throws away a lot of information. Imagine a similar algorithm with an increasing number of zones. Loosely speaking, "in the limit" as the number of zones gets bigger, all we are really doing here is counting heart beats.<br /><br />So why not just count heart beats, maybe with some clever transformations? For example, if you ride for an hour and your average heart rate is 150 bpm, your heart beat 9,000 times. If your resting heart rate is 60 bpm, that's 3,600 beats per hour, and you could subtract that to arrive at a figure of 5,400 excess beats per hour.<br /><br />Better still, just count the gaps between heartbeats, since over any give time interval, the number of gaps is just one less than the number of beats. Beats are more or less instantaneous, while gaps vary--higher pulse rates mean shorter gaps. <br /><br />You could even construct a stress score that counts gaps, and weights the shorter gaps more heavily (with some sort of continuous transformation). If your resting heart rate is 60 bpm, than the gap between beats is one second, and you could assign a weight of zero to any gap one second or longer. Of course, if you are dead, by definition your stress score would be zero. Just kidding.<br /><br />All fancy math aside, the point I'm trying to make is that the Strava suffer score, underneath it all, is about counting heart beats, and just what you can do with that sort of information opens up some interesting questions. <br /><br /> <br /><br /><br /><br /> Michael Barneshttps://www.blogger.com/profile/06466641993175128509noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-61711591331405427282014-11-30T22:00:11.214-08:002014-11-30T22:00:11.214-08:00I have been running into a slightly different issu...I have been running into a slightly different issue in relation to Suffer Score... If I do an exercise that has GPS enabled, for instance RUNNING, Suffer Score is based on "Moving Time" NOT total elapsed time (even if you manually change workout to RACE or WORKOUT)<br /><br />I would like to be able to train and go for a run and do static exercises (e.g. Squat Jumps) and then continue running. However, currently my heart rate for the period of time spent doing squat jumps is not contributing to my suffer score :(<br /><br />Any ideas?Anonymoushttps://www.blogger.com/profile/16704385531727748729noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-24361503803165450942014-11-19T06:20:26.029-08:002014-11-19T06:20:26.029-08:00Well the way I see it - suffer score is (or rather...Well the way I see it - suffer score is (or rather should/could be) an estimate of how hard You were working (whatever that might be) based on Your HR.<br />It doesn't really matter whether You were running or cycling or doing something else - You got Your "pump" (Your heart that is) working hard. In this regard different activities could potentially be compared in terms of how much stress they caused to You heart.<br />Unfortunately Strava obviously doesn't have the same view on SS, because it is a lot harder (in terms of heart stress) to get high SS in cycling then it is in running.<br />Some kind of normalized SS would be much more informative if You could (provided You have Your zones set correctly) only get SS of maximum around 100 in one hour - that would correlate with FTP power/Lactate Treshold.<br />You could get Your heart working harder for shorter time, of course, or maintain hours of less stress, but getting over 100 in an hour would mean, You got Your zones set too low...<br />In fact according to my experiences getting SS for Cycling over 100 in an hour is almost impossible for me, but for running i can get over 250 in less then an hour...|<amachttps://www.blogger.com/profile/08558965163075639560noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-11390366678697017962014-11-19T05:01:02.466-08:002014-11-19T05:01:02.466-08:00I think "suffer score" is fairly arbitra...I think "suffer score" is fairly arbitrary -- it's whatever Strava decided it should be based on their participants. I'm not sure comparing running to cycling is valid on any objective basis other than they took some sort of average of their cycling and running activities.djconnelhttps://www.blogger.com/profile/01484858820878605035noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-28482123467749509602014-11-06T22:33:13.228-08:002014-11-06T22:33:13.228-08:00Hi! I was wondering for some time, how I can get S...Hi! I was wondering for some time, how I can get SS of over 200 in an hour when running (my best was 247/245pir in 51minutes in 10km race), but biking uphill and giving my best would only get me about 120/100pir in about two hours (of which about an hour was working at full going up).<br />I'm also pretty sure I have zones set about right. I'm estimating my 1 hour max HR(FTP HR) to about 161 in it is in the middle of Strava's Z4(156-167), and getting into Z5(>167) is very hard (on bike I've been there only few times). Getting over 170 for me is "suffer as hell" :)|<amachttps://www.blogger.com/profile/08558965163075639560noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-1238728221297616522014-11-04T04:43:31.854-08:002014-11-04T04:43:31.854-08:00Thanks for the comment! If I run the cycling calc...Thanks for the comment! If I run the cycling calculation for your run I get 46.03, but Strava reports 129. So you're right -- it needs to be recalibrated! This could be done easily enough with several runs with different HR distributions. But that rate of inflation, which is a factor of 2.8 in your case (and this may be all there is to it: an inflation by a factor 2.8) seems high. Consider <a href="http://www.ironman.com/triathlon/events/americas/ironman/world-championship/results.aspx#axzz3I6RTl7Qn" rel="nofollow">Ironman results</a>: the average of the top 3 was 4:27 on the bike and 2:51 on the run, a ratio of 1.56. If Ironman is balanced then the ratio should be closer to this, assuming average heartrates are somewhat similar. I'd need to look at a few activities to isolate coefficients though (it's a simple algebra problem).djconnelhttps://www.blogger.com/profile/01484858820878605035noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-31656932312282759662014-11-03T22:50:25.965-08:002014-11-03T22:50:25.965-08:00Hello!
Nice interesting article!
Your decoded SS ...Hello!<br /><br />Nice interesting article!<br />Your decoded SS formula seems to work well for bike rides (http://www.strava.com/activities/213873617/heartrate)<br /><br />But I'd say Strava calculates SS differently for running, see for example this workout:<br />http://www.strava.com/activities/215099305/heartrate<br />Only 25 minutes in Z4 and 15 in Z3 got me SS of 130.<br />Could You please also try to decode running SS?|<amachttps://www.blogger.com/profile/08558965163075639560noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-31925392084983910062013-11-29T14:46:32.040-08:002013-11-29T14:46:32.040-08:00t1 is the time in zone 1. I say "in hours&q...t1 is the time in zone 1. I say "in hours" to be easier for people to understand, but really that's redundant. Time has units of "hours" but it can also have units of "minutes" or "seconds", etc. Suffer score has no units. So I need to multiply t1 by something which has units of 1/hours. Then the hours will cancel (one in numerator, one in denominator) and I'll be left with something with no units, which is what I want.<br /><br />If I were to specify time in minutes instead of hours then I'd need to multiply by a unit conversion factor, for example (1 hour / 60 minutes).<br /><br />This is common in physics. For example, if I have a velocity (units distance/time) and multiply it by a time (units time) the times cancel and I'm left with distance, which is what I want for riding a particular speed for a particular time. When I put the multiplier in units 1/hr, you're guaranteed to get the correct result.<br /><br />It's always important to keep track of units. Suffer score, in order to be simple to understand, is presented without units: you can't say "my suffer score was 100 hours" or "my suffer score was just over 4 days" or "6000 minutes".... it's just 100.djconnelhttps://www.blogger.com/profile/01484858820878605035noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-61037277989406806252013-11-29T14:20:15.944-08:002013-11-29T14:20:15.944-08:00thanks for the quick reply, but HR hours in that ...thanks for the quick reply, but HR hours in that particular zone and Tx hours in that particular zone?oscarhttps://www.blogger.com/profile/03680163614791675827noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-63064978000478996652013-11-29T13:41:16.983-08:002013-11-29T13:41:16.983-08:00"hr" is units "hours". So it&..."hr" is units "hours". So it's not a variable, but a unit constant.djconnelhttps://www.blogger.com/profile/01484858820878605035noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-43927200607169550032013-11-29T10:58:27.468-08:002013-11-29T10:58:27.468-08:00Hi Dj,
I am confused. If T1 is equal to the numb...Hi Dj,<br /><br />I am confused. If T1 is equal to the number of hours in zone 1 and HR is equal to the number of hours in zone 1, then T1 = HR.<br /><br />So, for axample (and examples are sorely needed), if I walk 30 minutes in zone 1 then T1 = .5 and K1 = 12/.5 so T1 * K1 = 12oscarhttps://www.blogger.com/profile/03680163614791675827noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-65759010897919649762013-05-23T05:44:55.407-07:002013-05-23T05:44:55.407-07:00Not much, Franz. TIme is limited for these projec...Not much, Franz. TIme is limited for these projects, unfortunately. Most of my blog writing is done on crowded Caltrain commutes.<br /><br />But the training score, fitness, and fatigue are very similar to CTL, TSB, and ATL from TrainingPeaks. Those parameter names are trademarked. GoldenCheetah has similar metrics. The issue is you need to use a power meter <i>every ride</i>. I didn't use one during the Berkeley Hills Road Race, a considerable physical stress, and so that shows up as a total rest day in my metrics. It takes months to flush that omission from my scores.<br /><br />At GoldenCheetah I proposed an algorithm that a regression could be done on distance and climbing of existing rides to estimate these scores for riders without power data. Strava could also use estimated power. Anything is better than assigning zero score to a ride without power meter data, assuming there's no data from car or train rides, for example, contaminating these.djconnelhttps://www.blogger.com/profile/01484858820878605035noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-13361783493140631642013-05-22T23:04:41.703-07:002013-05-22T23:04:41.703-07:00Have you written about the other new Strava premiu...Have you written about the other new Strava premium features when you have a power meter, such as the fitness score, training load and fatigue?Anonymoushttps://www.blogger.com/profile/06204423070355903591noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-57159155793735013052013-05-02T07:29:29.831-07:002013-05-02T07:29:29.831-07:00very work to find this power (watts) algoritm
the ...very work to find this power (watts) algoritm<br />the results are very close to strava em endomondo<br />http://www.ihpva.org/HParchive/PDF/hp48-1999.pdf<br /><br />calories =(((2,706*total weight in kg*Velocity kph*%elevation)+(1,247*10^(-2)*Cda*(velocity kph+wind kph)^2*velocity kph)+(2,706*Crr*total weight in kg*velocity kph))/0,95)*3.90265912226099*time hrs *2<br /><br />Watts = Callories* 1000 / 3600<br /><br />crr for mtb = 0,0046<br />Cda = 1 * 0.0293 * (Height in mts ^ 0.725) * (Pweight kg ^ 0.425) + 0.0604 + 0.2645<br />Anonymoushttps://www.blogger.com/profile/11817376530238064455noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-16609593301117361772013-05-01T16:18:56.423-07:002013-05-01T16:18:56.423-07:00thanks for this!
I agree with thehomme and yourse...thanks for this!<br /><br />I agree with thehomme and yourself: time spent in z2 should have less incidence on suffer score and time spent in z4 and z5 should be even higher.<br /><br />Some fairly easy endurance long runs get higher SSS than tempo runs and hill repeats.philgo20https://www.blogger.com/profile/14529107190348156600noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-3409842240841775002013-04-30T16:44:47.999-07:002013-04-30T16:44:47.999-07:00I am not certain how power is calculated, but unle...I am not certain how power is calculated, but unless rider weight + bike weight on Strava = the weight of everything together, including water bottles, water, food, clothes, helmet, shoes, tools, etc, the power calculation will be biased low. The issue here is I suspect most users use their bare bike mass and their naked body mass, so power estimates tend to be too low.djconnelhttps://www.blogger.com/profile/01484858820878605035noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-14796502571084415612013-04-26T22:14:26.774-07:002013-04-26T22:14:26.774-07:00Nice analysis! Have you delved into how they calcu...Nice analysis! Have you delved into how they calculate power at all?nick.garthttps://www.blogger.com/profile/03791860082734765484noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-65326811309336422302013-04-19T05:29:37.574-07:002013-04-19T05:29:37.574-07:00No: (12/hr) is a factor with units per hour. So i...No: (12/hr) is a factor with units per hour. So if you multiply (12/hr) by (2.5 hr) then the hours cancel, and you get 30. If you multiply (12/hr) by (250 minutes) you need to multiply by (1 hr / 60 minutes) and now the hr, minutes both cancel and you are left again with 30. You do this separately for each HR zone, counting the number of individual seconds spent in each, and you end up with total suffer score.djconnelhttps://www.blogger.com/profile/01484858820878605035noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-16065386685870906732013-04-19T02:55:51.414-07:002013-04-19T02:55:51.414-07:00This comment has been removed by a blog administrator.Anonymoushttps://www.blogger.com/profile/11817376530238064455noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-67015612465167498222013-04-19T02:55:06.853-07:002013-04-19T02:55:06.853-07:00I still not understand!
so if k1= 12/hr
and hr mea...I still not understand!<br />so if k1= 12/hr<br />and hr means the time spent in the zone and then i multiply for t1 that is time spent in zone 1... the in the final i have just 12+24+... because the hr cut t and just leave the score for each zone??<br />I know that some of my cal is not correct, but what??? pls give an example!<br /><br /> K1 t1 + K2 t2 + K3 t3 + K4 t4 + K5 t5<br /><br />where:<br />t1 = time in hours in zone 1<br />t2 = time in hours in zone 2<br />t3 = time in hours in zone 3<br />t4 = time in hours in zone 4<br />t5 = time in hours in zone 5<br /><br />With coefficient roughly equal to the following (may be off by 1/hr):<br />K1 = 12/hr<br />K2 = 24/hrAnonymoushttps://www.blogger.com/profile/11817376530238064455noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-13739891106189179182013-04-16T04:06:57.616-07:002013-04-16T04:06:57.616-07:00Total hours during which HR was in those particula...Total hours during which HR was in those particular zones and data were recording. So if it jumps from zone-to-zone, they estimate time in each zone.djconnelhttps://www.blogger.com/profile/01484858820878605035noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-27759152587960805702013-04-16T03:56:47.854-07:002013-04-16T03:56:47.854-07:00Suffer score = K1 t1 + K2 t2 + K3 t3 + K4 t4 + K5 ...Suffer score = K1 t1 + K2 t2 + K3 t3 + K4 t4 + K5 t5<br /><br />where:<br />t1 = time in hours in zone 1<br />t2 = time in hours in zone 2<br />t3 = time in hours in zone 3<br />t4 = time in hours in zone 4<br />t5 = time in hours in zone 5<br /><br />With coefficient roughly equal to the following (may be off by 1/hr):<br />K1 = 12/hr<br />K2 = 24/hr<br />K3 = 45/hr<br />K4 = 100/hr<br />K5 = 120/hr<br /><br />ok... but hr means the total of hours spent in the exercise??Anonymoushttps://www.blogger.com/profile/11817376530238064455noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-91820564181064012002012-10-01T17:27:48.933-07:002012-10-01T17:27:48.933-07:00Thanks, Tina! I have been to Saigon and really li...Thanks, Tina! I have been to Saigon and really liked it. I didn't try cycling there, but other places in Vietnam, like De Lat 300 km to the north, seemed like excellent cycling locations.<br /><br />On the out-and-back problem I have spoken to Strava in person about that and I expect it will be solved eventually. The problem is that the matching between the start and end point is relatively loose. So if you do an out-and-back, and match the start and finish (the same point), then if you have visited 80% of the points in between (80% of the route, cutting short 20%), then it might match you. What they need to do is to add in special checkpoints which must be matched in addition to the start and finish. For an out-and-back that would be the turn-around point. I had expected they would have done this by now but I think their priorities have been elsewhere, for example on handling the enormous number of new users.<br /><br />I recently ran a 10 km race and it gave me credit for the 10 km race segment using only 8 km of my data: after 8 km I passed close to the finish line and it concluded I had matched the segment. So my time for that segment was extremely good... same problem.djconnelhttps://www.blogger.com/profile/01484858820878605035noreply@blogger.comtag:blogger.com,1999:blog-1564958057737541664.post-29843561676541961002012-10-01T16:26:57.350-07:002012-10-01T16:26:57.350-07:00This comment has been removed by a blog administrator.Tinahttps://www.blogger.com/profile/12361755545952230504noreply@blogger.com