Power

img_87
img_87 Posts: 60
edited August 2016 in Road beginners
Hi all,

Wasn't sure where to put this but given that i am slightly worried i should know the answer i decided beginners was the best place for it.

Having watched the Olympic cycling there is obviously a lot of talk about power. The numbers are astonishing but I soon realised that i had absolutely nothing to compare it to. No frame of reference.

So my question is.... is there a way of measuring ones maximum power output? Is there somewhere you can go and do a power test?

i have no real interest currently in monitoring my power when i ride but would be curious to know, as a one off, what i was capable of.

Apologies if i am being an idiot.

cheers, Ian
«1

Comments

  • Anonymous
    Anonymous Posts: 79,667
    In the gym on a wattbike would be my best advice. You can do all sorts of fitness tests there.

    Not sure how much it would cost, but all I can say is, prepare to be disappointed, however low your aspirations may be ;)
  • The usual measure apart from max power is FTP - Functional Threshold Power which is the output you can sustain for 1 hour. Most of the time that's done by going hard for 20 minutes and then taking a percentage of that.

    In order to find it out you'd need the likes of a power meter on your bike or a smart trainer or the likes of a gym bike.
  • bflk
    bflk Posts: 240
    If I heard him right Chris Boardman during the TP said the lead guy was putting out 800W which he said was five times what someone might do 'just riding in the park'. I had to do a double take cos I am pretty confident I don't put out 160W pootling in the park? Or even riding quite hard on the road on the flat leastways. Of course I don't have a power meter but I look at those who do on Strava leaderboards.
  • StillGoing
    StillGoing Posts: 5,211
    bflk wrote:
    If I heard him right Chris Boardman during the TP said the lead guy was putting out 800W which he said was five times what someone might do 'just riding in the park'. I had to do a double take cos I am pretty confident I don't put out 160W pootling in the park? Or even riding quite hard on the road on the flat leastways. Of course I don't have a power meter but I look at those who do on Strava leaderboards.

    The flying lap sprints more like 2-2500 watts but they won't sustain it for very long. You'll be surprised to see how little wattage you're putting out and 160 watts is being pretty optimistic for pootling in the park. Think more in double figures.

    Functional Threshold Power of FTP and watts per kilo is a good indicator of someone's ability.

    Screen_Shot_-_Power_calculator.1408529835.png

    power-profiling-chart.gif
    I ride a bike. Doesn't make me green or a tree hugger. I drive a car too.
  • milemuncher1
    milemuncher1 Posts: 1,472
    Personally, I don't know how much POWWWWERRRRRRRRRR I produce, nor do I care, but those who do, seem to speak highly of Watt bikes, and 'in crank / pedal' power meters, linked up to their ( insert wearable tech). Nothing irritates me more than someone asking me how much power I put out, or worse, what my 'cadence' is, whilst riding. My stock answers are "enough to get up that hill we just rode up" and "I'm not tired, and my BB / chain has lasted for lots of miles, so it's about right". As you said in your O.P. the figures sound good, but I've no idea if they are or not.
  • bflk
    bflk Posts: 240
    On the basis of a local 7M TT course which is flat and out/back I am likely producing <200W (or even << 200W) riding solo on it (ie not an actual TT). That's estimated from data from the riders who have power meters. It takes me over 20 min so for me roughly corresponds to the 20min power test (obviously the top guys are more like 14/15 min though). I weigh 62kg. My bike setup and riding position is probably poor so I'm not that bothered really.

    https://www.strava.com/segments/1246484
  • bflk wrote:
    If I heard him right Chris Boardman during the TP said the lead guy was putting out 800W which he said was five times what someone might do 'just riding in the park'. I had to do a double take cos I am pretty confident I don't put out 160W pootling in the park? Or even riding quite hard on the road on the flat leastways. Of course I don't have a power meter but I look at those who do on Strava leaderboards.

    Yes obviously Chris Boardman's idea of pooling along in the park is probably different. For me pootling along with not much effort means <100W. Which would be 1/8th of those cyclists efforts. 160W would be hard riding. But for many on here 160W would be hardly coasting.
  • slowbike
    slowbike Posts: 8,498
    philthy3 wrote:
    Functional Threshold Power of FTP and watts per kilo is a good indicator of someone's ability.

    https://www.britishcycling.org.uk/membe ... lculator-0
    Puts me in average Cat4 - which is probably about right considering I don't bother training as such :)

    Putting my head above the parapet - here's some stats from this old(er) fart... (measured using Stages PM)
    I can put out over 750w - just not for very long.
    I can sustain >300w for a few minutes - usually "blasting" up a hill (on a road bike)
    I average ~250w over a ten mile TT (on a TT bike)
    I averaged 235w over an hour's hilly TT (on a TT bike)

    So - nothing special there at all - numbers that are put out by blokes 10+ years older than me at the club.

    Here you go - another link
    http://www.cyclingpowerlab.com/CyclingPowerOutput.aspx - that's quite interesting - the 10mile TT stacks up with my results
  • slowbike
    slowbike Posts: 8,498
    Yes obviously Chris Boardman's idea of pooling along in the park is probably different. For me pootling along with not much effort means <100W. Which would be 1/8th of those cyclists efforts. 160W would be hard riding. But for many on here 160W would be hardly coasting.
    hmm - you need to do more training! ;)
  • Slowbike wrote:
    Yes obviously Chris Boardman's idea of pooling along in the park is probably different. For me pootling along with not much effort means <100W. Which would be 1/8th of those cyclists efforts. 160W would be hard riding. But for many on here 160W would be hardly coasting.
    hmm - you need to do more training! ;)

    Why? Who are you to say what I should or shouldn't do or what an acceptable power output it? Because it's different from yours? Sod off.
  • StillGoing
    StillGoing Posts: 5,211
    Slowbike wrote:
    philthy3 wrote:
    Functional Threshold Power of FTP and watts per kilo is a good indicator of someone's ability.

    https://www.britishcycling.org.uk/membe ... lculator-0
    Puts me in average Cat4 - which is probably about right considering I don't bother training as such :)

    Putting my head above the parapet - here's some stats from this old(er) fart... (measured using Stages PM)
    I can put out over 750w - just not for very long.
    I can sustain >300w for a few minutes - usually "blasting" up a hill (on a road bike)
    I average ~250w over a ten mile TT (on a TT bike)
    I averaged 235w over an hour's hilly TT (on a TT bike)

    So - nothing special there at all - numbers that are put out by blokes 10+ years older than me at the club.

    Here you go - another link
    http://www.cyclingpowerlab.com/CyclingPowerOutput.aspx - that's quite interesting - the 10mile TT stacks up with my results

    I used to be mid Cat 4 or high Cat 5 equivalent, but after an anaphylaxis resulting in full liquid resuscitation, my FTP has tailed off with lack of training and weight gain. I'm now untrained/bottom end Cat 5 but aiming to get back on it ASAP.
    I ride a bike. Doesn't make me green or a tree hugger. I drive a car too.
  • slowbike
    slowbike Posts: 8,498
    Slowbike wrote:
    Yes obviously Chris Boardman's idea of pooling along in the park is probably different. For me pootling along with not much effort means <100W. Which would be 1/8th of those cyclists efforts. 160W would be hard riding. But for many on here 160W would be hardly coasting.
    hmm - you need to do more training! ;)

    Why? Who are you to say what I should or shouldn't do or what an acceptable power output it? Because it's different from yours? Sod off.

    Why? Why not ...
    Who am I to say what you should or shouldn't do ... nobody that matters to you?
    Because it's different to mine? yup - it is ... you're right - 160w would be hardly coasting
    Sod off - if you like - can I go and ride my bike?
  • slowbike
    slowbike Posts: 8,498
    philthy3 wrote:
    Slowbike wrote:
    philthy3 wrote:
    Functional Threshold Power of FTP and watts per kilo is a good indicator of someone's ability.

    https://www.britishcycling.org.uk/membe ... lculator-0
    Puts me in average Cat4 - which is probably about right considering I don't bother training as such :)

    Putting my head above the parapet - here's some stats from this old(er) fart... (measured using Stages PM)
    I can put out over 750w - just not for very long.
    I can sustain >300w for a few minutes - usually "blasting" up a hill (on a road bike)
    I average ~250w over a ten mile TT (on a TT bike)
    I averaged 235w over an hour's hilly TT (on a TT bike)

    So - nothing special there at all - numbers that are put out by blokes 10+ years older than me at the club.

    Here you go - another link
    http://www.cyclingpowerlab.com/CyclingPowerOutput.aspx - that's quite interesting - the 10mile TT stacks up with my results

    I used to be mid Cat 4 or high Cat 5 equivalent, but after an anaphylaxis resulting in full liquid resuscitation, my FTP has tailed off with lack of training and weight gain. I'm now untrained/bottom end Cat 5 but aiming to get back on it ASAP.

    Fortunately my lack of performance this year is down to a significant decrease in riding rather than any medical issue - unless you can class having a 1yo I want to spend time with as a medical issue ... I seem to be doing just enough to keep it reasonable - power having dropped a little but not hugely - just checking my 10m TT last year to this years single effort - I'm 9 seconds down and only 30 seconds off my CPB set the previous year on a converted road bike. So happy enough there.... and the nice thing about TT's (about the only nice thing) is that you can compare your power/speed and see how you're getting on (or not in my case) ...
  • keef66
    keef66 Posts: 13,123
    philthy3 wrote:
    I used to be mid Cat 4 or high Cat 5 equivalent, but after an anaphylaxis resulting in full liquid resuscitation, my FTP has tailed off with lack of training and weight gain. I'm now untrained/bottom end Cat 5 but aiming to get back on it ASAP.


    I don't know what full liquid resuscitation involves, but I don't like the sound of it at all...

    Were you felled by a bee or a peanut? Or are you allergic to something more exotic?
  • fat daddy
    fat daddy Posts: 2,605
    FTP is a nice idea and probably bears some usefulness for TT's and racing. .... But they need another measurement called UTP which is Useable threshold power - based on either a 20min run to get 80% of your UTP or 1hr to get a full UTP you measure the amount of power you can realistically put down in that time without having to coast up to junctions, slow down for cars, stop at lights, panic brake for pedestrians, ease off in traffic, slow down to go round sharp bends ... in Bristol city Centre my UTP is 110w .. and that's pushing it ! :(
  • slowbike
    slowbike Posts: 8,498
    hah :)
    My commute can be as little as 2 junctions - one to turn onto the main road, one to turn off 9 miles later ... no lights, pedestrian crossings (or pedestrians for most of it), traffic or sharp bends to worry about
  • jgsi
    jgsi Posts: 5,062
    If you have been cycling consistently even for just a little while as beginner, then believe me , your easy spin around the block will have power figures in the 100s... just saying as long as you are pedalling properly and taking it ever so slightly seriously...... I have been riding with power meters a fair old while now so you get to know how these things work.
    Whatever UTP actually means in connection with power training and riding, I have no idea, it isnt a metric that is used or actually useful.
    To confirm, your FTP is the amount of power you are supposed to deliver for an hour based on 20 minutes or 2 x 8 minutes very hard efforts in a controlled environment.... you wouldnt really want to do it for an hour .. when you do it is called a 25mile timetrial and fuffin hurts like f uffin hell.
    Talking about urban commuting and power training has little relevance.
  • OnTheRopes
    OnTheRopes Posts: 460
    Slowbike wrote:
    Yes obviously Chris Boardman's idea of pooling along in the park is probably different. For me pootling along with not much effort means <100W. Which would be 1/8th of those cyclists efforts. 160W would be hard riding. But for many on here 160W would be hardly coasting.
    hmm - you need to do more training! ;)

    Why? Who are you to say what I should or shouldn't do or what an acceptable power output it? Because it's different from yours? Sod off.

    You really need to chill out
  • paul2718
    paul2718 Posts: 471
    I averaged 710W for 30s at the end of a race this evening. All that matters is that it wasn't enough.

    Boardman's comparison seems about right, but I think 800W might be an over-estimate. I found an old paper from 1996ish that suggested that for 60kph the powers for the four would be 607W, 430W, 389W, 389W. This would seem to be a good ball park even today.

    Paul
  • StillGoing
    StillGoing Posts: 5,211
    keef66 wrote:
    philthy3 wrote:
    I used to be mid Cat 4 or high Cat 5 equivalent, but after an anaphylaxis resulting in full liquid resuscitation, my FTP has tailed off with lack of training and weight gain. I'm now untrained/bottom end Cat 5 but aiming to get back on it ASAP.


    I don't know what full liquid resuscitation involves, but I don't like the sound of it at all...

    Were you felled by a bee or a peanut? Or are you allergic to something more exotic?

    Non-steroidal anti inflamatories. Went in for shoulder surgery and given pre-op pain killer in form of Volterol. Had it many times before without issue along with pain killers of the same family such as Ibuprofen and Neurofen. Went into anaphylaxis almost immediately. Luckily my wife was still in the room with me and called for assistance. Stridor developed and a full team working on me. Loads of saline going in and eventually the dreaded epipen into the thigh which I felt. BP dropped to 4 above coma. So 1pm on a Wednesday almost dead. 11am the next morning sent home to make appointment with allergy clinic to find out what the cause was. Wonderful NHS came back with mid September when this happened mid February. Went private and got the answer within a week.

    Funny thing is, if it hadn't have happened, we wouldn't have discovered my completely blocked artery. Discovered because of the big difference in BP readings from the arms. Ain't life wonderful.
    I ride a bike. Doesn't make me green or a tree hugger. I drive a car too.
  • StillGoing
    StillGoing Posts: 5,211
    Slowbike wrote:
    Fortunately my lack of performance this year is down to a significant decrease in riding rather than any medical issue - unless you can class having a 1yo I want to spend time with as a medical issue .

    Yep got a 2 year old myself and as the stay at home parent now I'm retired, I'm making up for the moments I didn't get with my two elder children during their formative years.
    I ride a bike. Doesn't make me green or a tree hugger. I drive a car too.
  • ugo.santalucia
    ugo.santalucia Posts: 28,172
    for a decent estimate of power output without spending money on technology, you need a hill... the longer and steadier the hill, the better and with a gradient of at least 6%.
    You then plot your time against the hill elevation, your weight etc in a calculator you can find online and you get a fairly accurate estimate of your power output based on simplified physics. You will find that as far as aerobic output goes (which means you can sustain that effort for at least 20 minutes), you are probably somewhere between 200 and 300 Watt depending on your level of fitness, higher if you are a well trained athlete, lower if you are a novice (or you are very small).
    left the forum March 2023
  • slowbike
    slowbike Posts: 8,498
    philthy3 wrote:
    Slowbike wrote:
    Fortunately my lack of performance this year is down to a significant decrease in riding rather than any medical issue - unless you can class having a 1yo I want to spend time with as a medical issue .

    Yep got a 2 year old myself and as the stay at home parent now I'm retired, I'm making up for the moments I didn't get with my two elder children during their formative years.

    Hmm - I'd love to be retired and spend more time with my little boy - he is our one and only (not planning on any more!) - so only have this one chance to get it right. Difficult because I miss my hobbies - but he is more important. :)
  • Alex99
    Alex99 Posts: 1,407
    paul2718 wrote:
    I averaged 710W for 30s at the end of a race this evening. All that matters is that it wasn't enough.

    Boardman's comparison seems about right, but I think 800W might be an over-estimate. I found an old paper from 1996ish that suggested that for 60kph the powers for the four would be 607W, 430W, 389W, 389W. This would seem to be a good ball park even today.

    Paul

    They're going faster than 60 these days :shock:
  • Alex99
    Alex99 Posts: 1,407
    fat daddy wrote:
    FTP is a nice idea and probably bears some usefulness for TT's and racing. .... But they need another measurement called UTP which is Useable threshold power - based on either a 20min run to get 80% of your UTP or 1hr to get a full UTP you measure the amount of power you can realistically put down in that time without having to coast up to junctions, slow down for cars, stop at lights, panic brake for pedestrians, ease off in traffic, slow down to go round sharp bends ... in Bristol city Centre my UTP is 110w .. and that's pushing it ! :(

    Hmm, struggling to see how the proposed UTP is a useful metric. Presumably, it would have a very poor correlation to fitness or FTP for very traffic-limited rides. A complete novice and a fit rider could come in with the same UTP, purely because they couldn't really ride properly.

    For up/down rides with some stops and starts, Normalized power is the best bet.
  • craigus89
    craigus89 Posts: 887
    [*]
    for a decent estimate of power output without spending money on technology, you need a hill... the longer and steadier the hill, the better and with a gradient of at least 6%.
    You then plot your time against the hill elevation, your weight etc in a calculator you can find online and you get a fairly accurate estimate of your power output based on simplified physics. You will find that as far as aerobic output goes (which means you can sustain that effort for at least 20 minutes), you are probably somewhere between 200 and 300 Watt depending on your level of fitness, higher if you are a well trained athlete, lower if you are a novice (or you are very small).

    Hmm, is that not what the Strava power estimates are? Presumably that is done via a basic calculator like you mention, but people are always saying they are pointless and not worth looking at.
  • Alex99
    Alex99 Posts: 1,407
    Craigus89 wrote:
    [*]
    for a decent estimate of power output without spending money on technology, you need a hill... the longer and steadier the hill, the better and with a gradient of at least 6%.
    You then plot your time against the hill elevation, your weight etc in a calculator you can find online and you get a fairly accurate estimate of your power output based on simplified physics. You will find that as far as aerobic output goes (which means you can sustain that effort for at least 20 minutes), you are probably somewhere between 200 and 300 Watt depending on your level of fitness, higher if you are a well trained athlete, lower if you are a novice (or you are very small).

    Hmm, is that not what the Strava power estimates are? Presumably that is done via a basic calculator like you mention, but people are always saying they are pointless and not worth looking at.

    Strava power estimates on hills can be OK. It depends on how good the topographical data is and how good your GPS trace is. The point it, if you have a local hill that you know is 8% for say, 2k, you can get a decent measurement using a stop watch and a calculation.
  • slowbike
    slowbike Posts: 8,498
    Craigus89 wrote:
    Hmm, is that not what the Strava power estimates are? Presumably that is done via a basic calculator like you mention, but people are always saying they are pointless and not worth looking at.

    ok - had a quick look at strava for a hill that I know I've ridden up with and without power. 0.9mile hill, same year, same bike - only difference is that the earlier one was done from a rolling start (on my way home from work) where as the second one was a hill climb TT ..
    6  	21 May 	11.3mi/h 	-	261W EST 	960.0 	5:15
    6  	 2 Nov 	11.3mi/h 	-	312W PM 	 960.0 	5:15
    

    Possibly under-estimated my weight and you need to take into consideration temperature and wind (it's an exposed hill).
    So it's not a million miles out ...
  • kingstongraham
    kingstongraham Posts: 26,132
    Slowbike wrote:
    Possibly under-estimated my weight and you need to take into consideration temperature and wind (it's an exposed hill).
    So it's not a million miles out ...
    20% difference is quite a lot isn't it?
  • ugo.santalucia
    ugo.santalucia Posts: 28,172
    If Strava knows everything needed, including the weight of your bike AND if you have a reliable segment and trace, then the number it churns out should be reliable. Problem is a lot of segments are not what they seem and others are not meaningful for the purpose of measuring a VAM or power output.
    Round here (Warwickshire) there are two climbs which I think are perfect for the job as they are both steep and regular: "Edge Hill" just off Kineton and Dovers hill from Weston Sub Edge. My time up the latter varies between 7 minutes and 7:15, which means at best we are looking at a VAM of 1150 mt/h, which in my case means just under 300 Watt.
    Bear in mind this is not fully aerobic, as I would not be able to go at that pace for longer... for longer fully aerobic climbs (which are hard to find in the UK) we are looking at 250-260 Watt and a VAM of 950-980 mt/h
    left the forum March 2023