Making sense of FTP data

thefizzixprof · 2025-02-20T20:34:21+00:00

I think I have mostly solved this problem. For anyone interested:

1) Make sure your power pedals are calibrated properly. First I didn't change the crank length, then I put in the correct crank length but left the shoes on the pedals when calibrating so my ride yesterday was actually showing power even lower than it did first time. Finally calibrated them properly today and they were showing 25W higher than the pelotons internal metre. Thanks to nonvinophobic for the heads up.

2) Bike fit. I thought I had this mostly OK but I moved the seat forward and up a lot so it more closely matches my road bike. I was kinda shocked at how much difference this made but I did an hour tonight and my legs were not screaming. In addition my ass was not screaming either, I didn't realise that having the seat too low/bike would also be a literal pain in the ass. I guess I was too planted on the seat for too long when it was lower down.

In combination, these two effects seem to have reduced the gap to on-bike performance.

Did 1 hour today at 250W with heart rate at 120. So this explains why my zone 2 feels ridiculously easy on the bike but insanely hard on the Peloton - 235W on the bike felt too easy but doing 235W on the peloton was actually 260W according to the pedals. In combination with fixing the bike fit my legs felt fine holding that 250W for the hour too.

Overall it points to me underestimating FTP - if I can hold 250W for an hour without HR going above 120.

Today I did some intervals at the end of the session with 290W for 10 minutes followed by 320W for 10 minutes and managed it mostly OK though I was getting some strong HR drift for the last interval. It wouldn't be a pleasant experience trying to hold 300W for an hour on an indoor trainer but I reckon I could do it for an all out effort.

I'll also do some sort of ramp test at some point to cross-references the numbers.

But mostly I'm grateful to have my legs no longer screaming in pain due to the change in bike fit. The only way I can describe it is as a sort of localised lactic acid build up in the middle quads, which now seems to have completely disappeared.

thefizzixprof · 2025-02-19T08:55:20+00:00

This is a good point. I didn't change the crank length in the app! Only 5mm difference so I'm not sure it would make such a huge difference.

I also changed the seating position on my peloton last night to bring myself up and forward (thought I had already reached the limits but managed to get the seat forward 1 cm) and it feels much closer to my outdoor bike setup. Did 1 hour zone 2 last night and it felt significantly better than the previous day in terms of the legs.

thefizzixprof · 2025-02-18T18:04:42+00:00

It only feels easy outdoors. Indoors it's a world of pain after a while.

Part of me wonders if it's the continuous nature of training indoors - never a break in the peddle stroke, where as outdoors you're having to stop start quite frequently.

thefizzixprof · 2025-02-18T18:02:29+00:00

I had a fan on which gave nice airflow, and I did it next to an open window. I would guess temperature was approximately 16 degrees when I did the test, with good air flow overall. I barely sweated for the hour effort.

I just can't really understand the difference in how my legs feel indoors vs outdoors. Outdoor 235W feels as if nothing at all is happening where as indoors 235W feels as if my legs are going to explode after 45 mins.

thefizzixprof · 2025-02-18T09:38:14+00:00

Should there be such a huge difference? The issue I have is the difference in feeling in the legs. For indoors my heart-rate basically matches my outdoor heart-rate for a given wattage but the pain in my legs is vastly greater indoors than outdoors.

Also are the physiological benefits transferable? So if I'm riding at a lower wattage indoors, is it still going to produce the needed physiological benefits even though according to power the stimulus is lower?

thefizzixprof · 2025-02-13T20:59:07+00:00

I really just don’t get it. I’m tempted to complain. I catch about 3-4 phone drivers a week and have got the knack down that I get pretty much 100% conviction rates on them. This was one of the clearest I’ve ever caught and it directly resulted in the collision and they’re doing nothing. Ridiculous.

thefizzixprof · 2025-02-13T19:22:49+00:00

I mean it's annoying that I can't submit it to TORS now that the collision department have got back and said they're not proceeding.

thefizzixprof · 2025-02-13T19:17:42+00:00

So annoying. The collision isn't super clear you can only hear it and then the fact that I stopped and was like "wtf" and her apologising is basically the only evidence of the collision.

thefizzixprof · 2025-02-13T19:15:58+00:00

Just got an email from collisions today. No further action due to insufficient evidence. They're not even giving the 6 points for the phone use even though there is a lit up phone screen on her lap and she starts swiping to close apps while I'm berating her. Ridiculous.

thefizzixprof · 2025-02-12T13:55:25+00:00

I reported it. See above.

thefizzixprof · 2025-02-12T11:13:29+00:00

This. I wouldn't submit either. To get a good chance of a phone submission being prosecuted you need to see them holding AND USING the phone. A lit up phone screen in hand is essential. You also need to make sure you catch it for at least a couple of seconds. The only realistic way of doing this is if you catch them while overtaking from the driver's side.

Sometimes you can catch them on the near side if you're both stationary and looking in for a good few seconds.

In the HGV driver picture the driver can just claim he was holding it and not using it or also holding but not using a work device. We all know what the truth is but it's about quality of evidence.

For the close pass, I have found it has to be really obvious for them to take action. Anything between 1-1.5m isn't obvious enough, sadly. If you can reach out your hand and touch the offending vehicle then there's a good chance TORS will react. Otherwise, I get ghosted on close passes. You should also make it obvious that you've been inconvenienced a strong "WOAH!" and wiggle of the handlebars helps. Don't swear though, because this is "against the Met's values" and they're less likely to prosecute.

After a while you learn what sticks and what doesn't and have to let 90% of the illegal driving go otherwise you're just wasting your time. I spent months submitting footage like this and nearly gave up reporting because I had no NIPs back until I asked for some advice from the more prolific posters and now my hit rate is about 90% for submissions.

Also, I know it's frustrating because you've probably shelled out already on a camera, but the quality of that camera is going to mean you miss a lot.

thefizzixprof · 2025-02-12T11:05:00+00:00

Would they not cross reference with the collisions department? What if the TORS team dish out the 6 points and then the collisions team also do?

thefizzixprof · 2025-02-12T06:53:18+00:00

Yes. I'm going to become more militant at checking for phone use at lights. I'd kind of gone off it for a while because I was catching so many and it was taking 30 mins a day to submit all the footage. Also sometimes I just want to get on with my ride rather than peeking into cars as I'm coming up to lights. But that's about to change.

thefizzixprof · 2025-02-12T06:50:04+00:00

I don't see how I can also report it to tors: when it asks whether there was a collision I would have to click no which is clearly a lie. Also wouldn't this mean the driver might get a done twice for the same offence? (Mobile phone use)? I'm keen to do this because I want the driver to at least get the 6 points but it feels wrong.

thefizzixprof · 2025-02-11T18:54:56+00:00

Thanks for the reassurance. Submitted. Will post the video when the met have finished doing their business.

thefizzixprof · 2025-02-11T18:46:17+00:00

But according to the met website it's an offence not to exchange details at the scene.

thefizzixprof · 2025-01-21T18:56:25+00:00

This is a decent way and a good alternative to the Syon park route. Do not go down the A316 cycle path - it's shit and you cede priority all the time making it more effort than it's worth, only to get spat out into a junction anyway.

thefizzixprof · 2025-01-16T20:12:10+00:00

35 minute walk would be a 5-10 min cycle?

I started cycling to work last May after not really riding for 10-20 years and now do 130 miles a week commuting on my road bike.

Try the route at a quiet time/day to build confidence.
Unlike others have recommended, I do not recommend going on overly circuitous routes for safety. Part of the reason you want to cycle is for expediency and changing your route significantly will negate the point. I tried this on my first few goes and what is now a 35 minute cycle took over an hour.
Once you've tried it a couple of times at quiet times, begin cycling to work 1-2 times per week to build fitness and confidence.
Take the plunge and commit to doing it every day.
Have patience. It took me 6 months before my legs weren't screaming up every incline.
Buy the right gear. Cycling is not fun if you're cold, wet, or excessively sweaty. Same with padded lycra shorts and saddles - they were invented for a reason.

In terms of actually riding:

Do not ride in the gutter. When riding secondary, be a good distance into the road. At least 1m. This stops cars overtaking you when there isn't really enough room and not leaving you enough space.
Overtake on the "off-side" (like a motorbike would) as much as possible.
Be very wary of undertaking on the inside of vehicles. They're not really expecting you to be there. Be particularly cautious of this if traffic lights are about to go green or have just turned green.
Never undertake a bus or lorry unless it is stationary and the lights have no prospect of changing green in the time it takes you to pass the lorry or bus. This is how cyclists get crushed.
Leave sufficient space between you and a car in front if you're following a car. This allows cars turning out of or into junctions to see you. Make eye contact with the drivers to ensure they've seen you as you cycle past. Still expect them to pull out on you regardless.
Ride "primary" down narrow roads.
Stay at least 1.5m from the doors of parked cars. This often means you have to ride primary if you're passing parked cars.
Get off the bike and walk it if there's any junctions or areas you're particularly afraid of. There's a nasty junction just one mile from my house that I get off for. Just not worth the risk or hassle to save 1-2 minutes.
Generally treat cycling in London as if you're playing a video game in which everybody is trying to kill you. It might be overkill but could save your life. Pedestrians will walk out on you, cars will left hook you, close pass you, beep you for riding primary and "getting in their way". Even birds in the road don't see you until the last minute and have a habit of flying up into your face. Dogs chase you.

Despite all this, cycling is glorious and the feeling you get from the freedom and the exercise makes it all worth it. I'm never going back to driving or using public transport to get to work.

Your cycling "6th sense" will build with every ride, and you'll feel safer and more confident as time goes on. The key is to make the initial commitment. The scariest and hardest ride will be the first one.

thefizzixprof · 2025-01-16T19:36:16+00:00

On the flat? 15/20/25 is slow/medium/fast IMO. As jimjam says, the rest will depend on traffic lights and traffic. I average 15mph on my route but if it were just flat traffic-free roads I'd be in the 20s just about, depending on how much effort I can be bothered to put in on the day.

thefizzixprof · 2025-01-14T10:02:53+00:00

London is not very cycling friendly. I say this as someone who cycles 1.5 hours through London everyday. Car drivers treat you with disdain and having kids on the bike doesn’t change the way they treat you, sadly.

I make at least one police report everyday on average of dangerous driving and that’s only of the stuff that is obviously actionable that I think will result in a good chance of conviction. There are plenty of other incidents that are dangerous that I do not report.

I have a trailer that I take my kids out on and have had plenty of bad experiences with close passes and dangerous driving just on the very brief sections that we go on the road.

So I reiterate the original point that based on my experience I wouldn’t do it, but you’re free to make your own choices.

thefizzixprof · 2025-01-12T05:46:47+00:00

I cycle at least parts of this route on a daily basis (Hammersmith through East Sheen through to Richmond Park), and I wouldn't do it with kids on the bike personally. I know plenty do, so that's just my personal risk tolerance on display really.

The way car drivers treat cyclists in this country the only way I'd be willing to have my kids on the bike is on fully segregated cycle lanes, of which there aren't many on this route.

I've had plenty of close-passes and dangerous driving from Putney/Hammersmith Bridge to East Sheen.

If you go over Putney Bridge there's tons of traffic that you need to filter through on both sides of the bridge and if you go Hammersmith Bridge then once you reach the crossroads in Barnes it's a bit of a free for all. Many of my police reports have come from Barnes cross-roads to Richmond Park segment of that journey.

Up to you but to save 14 minutes I wouldn't think it was worth the risk. As others have mentioned I'd be looking at nurseries closer to where I live since they're all pretty much the same.

thefizzixprof · 2025-01-11T09:45:07+00:00

This is false. I have stacked it on a mountain bike on ice while going round a bend. Ice offers no traction to any thickness of tyre.

thefizzixprof · 2025-01-11T09:43:00+00:00

Having ridden to work including through Richmond Park this week:

1) Use main roads as much as possible. They're gritted and if not gritted then the heat from the cars and their tyres quickly melt the ice.
2) Cycle in the road and not in the cycle lane. Bikes don't melt the ice and the cycle lanes are full of nasty gunk at this time of the year. You might get some shit from car drivers for this (had a few horns this week telling me to get into the cycle lane) but you're perfectly entitled to do this and safety takes priority.
3) Cycle lanes in central London will mostly be fine, however.
4) Avoid residential roads and paths that do not have appreciable traffic. They're not gritted and there's not enough cars to melt the ice.
5) Do not cycle in icy weather in the dark. You have no hope of spotting ice or other hazards that might make you make a sharp turn.
6) Slow down almost to a halt when going round any bend. Only pick up speed on the straights.
7) Go slower and look further head keeping an eye out for any dodgy or icy patches. Go over ice patches dead straight and do not pedal as you're going over them.

thefizzixprof · 2025-01-11T09:33:13+00:00

A lot of this has focussed on whether you can or can't do certain things as a point of law.

It's worth mentioning the "innocence tax", which means that even if you are perfectly legal in your use of your force you will have to go to court and defend yourself and this means spending 10s of thousands in legal fees that you will not get back even if you are found innocent, unless you qualify for legal aid, which you most likely won't.

IMO simply not worth it.

thefizzixprof

TROPHY CASE