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Skinny riders how do you fuel on rides 3 hours plus?

jhegjheg Posts: 15
I've often heard people say they hit a wall then get a second wind but I wonder if body fat alone helps some riders go further. I'm quite tall and very skinny and I find if I go out on a 3 hour ride if I don't fuel during that ride I'm going to start feeling depleted after 2 hours for a Z3+ ride yet other heavier guys seem to be able to sustain for longer. I know that fitness comes into it but all things being equal assuming equal fitness does a skinnier guy with less fat reserves need to stay more topped up than a heavier guy?

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  • webboowebboo Posts: 2,712
    jheg wrote:
    I've often heard people say they hit a wall then get a second wind but I wonder if body fat alone helps some riders go further. I'm quite tall and very skinny and I find if I go out on a 3 hour ride if I don't fuel during that ride I'm going to start feeling depleted after 2 hours for a Z3+ ride yet other heavier guys seem to be able to sustain for longer. I know that fitness comes into it but all things being equal assuming equal fitness does a skinnier guy with less fat reserves need to stay more topped up than a heavier guy?
    Fat reserves are not about being fat. It's about ones ability to use fat as a fuel, we all have enough reserves what ever our body composition.
  • If you ride mainly on glycogen, which most people do, you have about 90 min-2 hours... so your experience is the norm. I need about 200 kcal every 45 minutes after that... that is one large energy bar.
    Mind you, I only average 26-27 kph, so you might well need more if you go faster
  • webboowebboo Posts: 2,712
    By training at your threshold you become able to use fat and glycogen, therefore being able to go for longer and faster without so much refuelling.
  • marykamaryka Posts: 745
    Are you sure their z3 is the same as yours? On a flat ride in particular, bigger/heavier/muscular people with good power will be putting out a lower percentage of their FTP to sustain the same speed as a smaller/lighter/skinny person with less power.

    e.g., someone with an FTP of 300w at 85kg can cruise along at 220w fairly comfortably for a few hours without needing to fuel that much, but if your FTP is only 270w at 60kg, 220w for you is a lot more work. There's some aero advantage to being skinny/small but only if you have a good position on the bike. Uphill is a different story of course.

    The harder you ride, the more you deplete glycogen more than fat and vice versa. So if you're fuelling on nearly all glycogen (a decently hard effort for a couple of hours) you will hit the wall long before someone riding at more fat-burning intensity.
  • MatthewfalleMatthewfalle Posts: 17,571
    I'm not sure about all the the technical stuff as above, but when I was racin' I was 6'1 and 70kg/maybe a kilo or two under. Looked well unhealthy but resting h/r of 34 belied element of fitness.

    I found that I was fine for 1hr 15ish min smash yourself to bits rides but anything coming up to 2hrs plus needed bananas, flapjacks, the suchlike (never been a great fan of gels but electrolyte drinks etc I'm fine with). Used to eat like a pig when getting home though.

    I think it's down to how your body works - try different things for 1 month long sessions and go with (literally) your gut feeling: just because it works for someone else doesn't mean it'll work for you.
    Postby team47b » Sun Jun 28, 2015 11:53 am

    De Sisti wrote:
    This is one of the silliest threads I've come across. :lol:

    Recognition at last Matthew, well done!, a justified honour :D
    smithy21 wrote:

    He's right you know.
  • mac9091mac9091 Posts: 196
    Bugs, flys, whatever ends up in my mouth seems to work for me :)

    Na I normally take out 2 energy gels and 1 bar, per hour for a ride of longer than 1 1/2 hours, unless there's a cafe stop involved. So a 3 hour sportive/ride would see me take 4 gels and 2 bars, of which i would expect to return with 1 bar and 1 gel (1st hour doesn't need any gels or bars) and my 1st gel would be around about 1 hour and 15. then something gel, bar, gel every half hour.

    If a cafe stop is involved then its 2 gels and a bar, just in case.

    My problem is getting enough fluids, i'll get through a bottle every half hour but can drag it to 45 mins if need be, so 2 bottles isn't enough for me regardless of hydration levels before the ride.
  • sungodsungod Posts: 12,705
    jheg wrote:
    I've often heard people say they hit a wall then get a second wind but I wonder if body fat alone helps some riders go further. I'm quite tall and very skinny and I find if I go out on a 3 hour ride if I don't fuel during that ride I'm going to start feeling depleted after 2 hours for a Z3+ ride yet other heavier guys seem to be able to sustain for longer. I know that fitness comes into it but all things being equal assuming equal fitness does a skinnier guy with less fat reserves need to stay more topped up than a heavier guy?

    you get 9kcal per g of fat, you get 4kcal per g of carbs (stored as glycogen)

    at low effort, the body can metabolise fat fast enough to keep going a long time - i.e. walking, or easy cycling, you can do that a long time

    afaik typical fat metabolism reaches c. 35g/hour, that's 315 kcal, training can help improve this, but there's a limit, and once effort reaches a certain point, the rate actually falls, eventually becoming negligible

    i.e. as effort increases, the proportion of energy taken from carbs increases until it accounts for almost all of it, this is what limits how long high effort can be sustained

    with the right mix of ingredients the typical maximum carb intake is about 90g/hr (2:1 glucose:fructose) which is 360kcal

    the need for fuelling on the go depends on how far/hard the ride is

    aside from training, i'm sure the others you mention will have stoked up well before the ride, you can do the same, if you start a ride with typical glycogen reserve, you've got c. 2000kcal (plus the larger fat reserve that'll help at lower effort) and you can replenish at 360kcal/hour

    fwiw i'm skinny, for rides where i'll be burning 4000-5000kcal i need to make sure i eat correctly in advance, and then i start topping up after 20-30 minutes (and post-ride i'll carry on eating to replace the defecit), otherwise eventually i'll grind to a lightheaded/dizzy halt, i've done that, it's not pleasant! but if i'm only going to need 1000-1200 kcal, i don't bother eating on the go, just make sure i start fuelled and get energy in as soon as the ride ends
    my bike - faster than god's and twice as shiny
  • cyclecliniccycleclinic Posts: 6,865
    I put it gel terms. Last sunday was a 93 mile 20mph ride (I am not sure what came over me). after the second how I had one Zipt Vit Gel and I had one every hour after that. Each gel is 51g of carbs.

    You can train your fat burning by doing lots of longer rides slower on little or no food but then when you want to perform eat or you'll bonk.

    If I have a big ride planned like tomorrow I make sure I eat before. Today I am carb loading (as I ride nearly every day I carb load every day I live on carbs) and tomorrow morning the breakfast will be a huge bowl of porridge. That way I am fine for the first 2 hours then I need to start eating.

    Had the light headed/dizzy feeling I had all to often when I went out for a longer ride stayed out for longer than I planned.

    It does not matter if you are skinny or big. There is only so much fat you can metabolise per hour and only so much ugar you can absorb and turn into glycogen per hour. Exceed these limits and you will bonk.
    http://www.thecycleclinic.co.uk -wheel building and other stuff.
  • drwaedrwae Posts: 308
    I'm 181cm and 65kg.
    For mid-distance rides (think 75km or so) with mid levels of elevation (750-800m gain in the 75km) I am absolutely fine getting up and doing the first half on an empty stomach, cafe stop half way through for a slice of cake and a coffee, complete the rest of the ride and stop at the chippy on the way home for some proper refuelling :):)
  • LeeDaLeeDa Posts: 82
    It all depends on the pace you are riding in relation to your fitness. Everyone has a point where your body flips from fat burning to using glycogen - for the unfit that may be immediately. Steady state training delays that flip so you can go harder whilst still using fat which is an abundant energy source. Threshold is training a different part of the energy system so not convinced that is the best place to be at for improving fat burning. For the typical weekend warrior glycogen burning is going to start pretty quickly and it's not abundant. If you want to find out where that flip happens for you just ride gradually harder until you feel a slight difference in breathing (deeper, a little louder) - that's the onset of glycogen usuage with the body expelling the resulting carbon dioxide. You can still be a relatively fast rider whist being inefficient at fat burning however if they were to address that area of fitness they are likely to be significantly faster and fresher at the end of a ride.
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