How Weight Loss Improves Cycling Performance

Everybody knows losing weight can improve your cycling performance and  make a big difference esp. in the hills where you have the most to gain by getting over them faster. But just how much off a difference? In the following examples lets compare two riders with a 30lb weight difference and see how that effects their performance when going up hills or inclines from 2% all the way up to 20% grade.

In a road race the hills often is where a racer has the most to gain on his opponents if he can go faster there, also in a TT you have the most to gain by getting up and over those hills as quick as possible so it doesn’t reduce your average speed/time as much. On the flats weight doesn’t matter as much but remember every slight incline you hit you might be going anaerobic while others are staying aerobic because they’re lighter. Rarely is a road truly flat, and it all starts to add up after a while, every little incline, esp. on the bigger steeper hills. Here’s a couple examples to highlight how much difference body weight can make in cycling in terms of power vs. weight and speed

Example 0% grade “flat” same speed

Well what about a slight incline of only 1% grade?

  • 1 mile hill
  • Incline 1%

Rider A

  • 215lbs
  • wattage 360w *Needs to put out 45watts more to match speed of Rider B
  • Rate: 21.10MPH

Rider B

  • 185lbs
  • wattage 353w *Can put out far less wattage and easily keep up with Rider A with 45watts less
  • Rate: 21.10MPH

Conclusion:  because of slight increase in rolling resistance we see a small difference in wattages on perfectly level road, but not much.

Example 1% grade same speed

Well what about a slight incline of only 1% grade?

  • 1 mile hill
  • Incline 1%

Rider A

  • 215lbs
  • wattage 360w *Needs to put out 45watts more to match speed of Rider B
  • Rate: 21.10MPH

Rider B

  • 185lbs
  • wattage 340w *Can put out far less wattage and easily keep up with Rider A with 45watts less
  • Rate: 21.10MPH

Conclusion:  Rider Since it’s almost flat you’d think that weight wouldn’t matter much, but guess again. A needs to put out 20watts more even with just a tiny incline of 1%, so even with a slight incline we already start to see that the heavier rider is starting to have to put out considerably more power, and most likely the bigger rider has a bigger cross section and more wind resistance too to make matters worse.

Example grade 2% same speed

Well what about a slight incline of only 2% grade?

  • 1 mile hill
  • Incline 2%

Rider A

  • 215lbs
  • wattage 360w *Needs to put out 45watts more to match speed of Rider B
  • Rate: 18.31MPH

Rider B

  • 185lbs
  • wattage 331w *Can put out far less wattage and easily keep up with Rider A with 45watts less
  • Rate: 18.31MPH

Conclusion:  Rider A has to put out 29watts more. So we see there’s still a huge advantage to being lighter even on a slight incline that you’d run into all the time on roads most people would call “flat”. When riding in race or Time trial at or near your threshold, 30watts is considerable difference and could easily be the difference that pushes one the heavier rider into the red, or to be dropped.

Example 5% incline same speed

  • 1 mile hill
  • Incline 5%

Rider A

  • 215lbs
  • wattage 360w
  • Time to top= 5.05

Rider B

  • 185lbs
  • wattage 319w *Can put out far less wattage and easily keep up with Rider A with 45watts less
  • time to top =5.05

Conclusion: Rider B would have to put out 41watts less! But at 5% we see the full penalty of that extra weight is in effect, but beyond 5% the wattage difference DOES NOT increase incrementally. It peaks at about 5%. And 41watts id a big difference, it could mean the difference of saying mostly aerobic where the the heavier rider is in the red going anaerobic riding at his absolute threshold just to keep up.

Example 10% incline same speed

In this example we increase the incline to see what going from a 5% incline to a 10% incline does

  • 1 mile hill
  • Incline 10%

Rider A

  • 215lbs
  • wattage 358w *Needs to put out 45watts more to match speed of Rider B
  • Rate: 6.75MPH

Rider B

  • 185lbs
  • wattage 314w *Can put out far less wattage and easily keep up with Rider A with 45watts less
  • Rate: 6.75MPH

Conclusion: Rider A would have to put out 44watts more to keep up with Rider B. So you see even if we double the grade from 5% to 10% the difference in wattage to keep up doesn’t double but actually stays about the same.

Example 20% grade same speed

Well what about a slight incline of only 20% grade?

  • 1 mile hill
  • Incline 20%

Rider A

  • 215lbs
  • wattage 360w *Needs to put out 45watts more to match speed of Rider B
  • Rate: 18.31MPH

Rider B

  • 185lbs
  • wattage 315w *Can put out far less wattage and easily keep up with Rider A with 45watts less
  • Rate: 18.31MPH

Conclusion:  Rider B again has to use 45watts less to go the same speed, so we see about a 1.5 watt per pound ratio of improvement.

Example 5% grade same power output

No let’s say both riders can put out the same wattage, then how much faster does the lighter rider get to the top on a easy 5% grade?

  • 1 mile hill
  • Incline 5%

Rider A

  • 215lbs
  • wattage 360w
  • Rate: 11.87MPH
  • Time to top= 46 seconds slower

Rider B

  • 185lbs
  • wattage 360w
  • Rate: 13.08 MPH
  • time to top = 46 seconds faster

Conclusion: Rider B gets to the top a whole 45 seconds faster traveling at 13.08 MPH vs. the heavier rider’s A speed of 11.87MPH, again a huge difference.

Example 10% grade Same Power

  • 1 mile hill
  • Incline 10%

Rider A

  • 215lbs
  • wattage 360w *Needs to put out 45watts more to match speed of Rider B
  • Rate: 6.79MPH

Rider B

  • 185lbs
  • wattage 360w *Can put out far less wattage and easily keep up with Rider A with 45watts less
  • Rate: 7.70MPH
  • Time: +1:36

Conclusion: If both riders put out the same wattage on a 10% 1 mile hill, the lighter rider would get to the top of the climb a hole minute and half faster then the other heavier rider that weighs 30lbs more. And you see the difference between the previous example of 5% grade vs. 10% in this example shows that as the hill gets steeper the lighter rider gets to the top even faster yet.

Example 20% Same Power

Well what about a slight incline of only 20% grade?

  • 1 mile hill
  • Incline 20%

Rider A

  • 215lbs
  • wattage 360w *Needs to put out 45watts more to match speed of Rider B
  • Rate: 3.53MPH
  • Time: 17:38

Rider B

  • 185lbs
  • wattage 360w *Can put out far less wattage and easily keep up with Rider A with 45watts less
  • Rate: 4.04MPH
  • Time: 15:25 = +2:13 faster, two minutes and 13 seconds faster

Conclusion: If you’re paying close attention you’ll notice that the steeper it gets the longer everybody has to spend working up that hill, and the steeper and slower the going, the more even a slight improvement in weight to power performance makes in getting to the top minutes faster, not just seconds!

Final Conclusion:

  1. As expected the heavy rider has to put out significantly more power to go the same speed as the lighter rider. There’s a lot to gain from being as light but powerful as possible, the lighter rider without even adding more fitness just losing weight is much more efficient and faster all around.
  2. Even the slightest of inclines forces the heavier rider to work significantly harder, only when the road is perfectly flat is there little difference but the real world most flat roads have plenty of slight grades. Imagine two riders near their FTP their functional threshold and every time there was even a slight incline the the heavier rider would go anaerobic because the run turns up slightly for a short distance, but this happens over and over again. Where the lighter rider might be able to stay aerobic even over slight inclines because of less weight penalty.
  3. You would think at first that the steeper the hill the greater the weight penalty, but it appears that the weight penalty ramps up quickly from 0-5% grades then after 5% it really doesn’t go up anymore as the hill gets steeper,  so in our example everything after 5% grade is about a 45watt difference.
  4. Another thing to take note of is how as the grade gets steeper the lighter rides gains more and more of a time advantage? But at the same time the difference between their speeds gets smaller, as 20% grade with both riders putting out the same power the lighter rider gets to the top over 2 minutes faster! This is because it’s such a slow steep hill that both riders are spending more time then ever getting over it vs an easier hill they’d get over much faster, so during that time the lighter rider’s half mile per hour faster speed really adds up in the end. Keep in mind both riders are going very slow but the difference between speeds is significant in relation of percentage to each other, so 0.5mph per hour difference normally isn’t much, but when you’re both going 3-4mph it’s around a 12%. It’s like the difference between 20mph and 22 mph on the flats which as you know is a big difference esp. for long distances.
  5. If you’re a heavier rider, try to get a slight lead before a big climb
  6. Don’t give up think the light guys are having to work less and less compared to you as it gets steeper, after 5% grade there’s not difference between that and 30% grade
  7. Keep in mind that drafting vs. not drafting can be about 30% difference in power out put, the last thing you want to do is be out in the wind then grinding up inclines while the light guys draft behind you up the inclines, make them work, or get behind them on the slight inclines to even the tables, on steeper grades where you slow way down and there’s not as much wind resistance it doesn’t do much to help you having them in front of you. So for example on rolling terrain you could let the light riders pull and draft up the hill, after it flattens out or declines it’s your turn to hammer, the best time to break away form them would be right as the hill levels out, break away

Spinning your way to faster riding

So every week I try to do a least one day of each  type  of  training endurance, intervals, sprints, efficiency/skills training etc.  Most rides are endurance or recovery rides and I’ll have my intensity day either be a race, or a strength session on or off the bike. My favorite is racing or hard group ride for my high intensity day, I get a bunch of hard intervals of various lengths in and some sprints and jumps. The powerfile for races is always very spiky and interval like, something hard to replicate in training, that’s why racing is important training I think. Nothing motivates me more to push myself to a new level of intensity then a good old fashion drag race on the bike!

So yesterday my goal was to do a combined efficiency/endurance day and try spinning at 100rpm+ for my 44 mile 2 hr ride I’ve been doing a lot lately. I wasn’t sure if I could do it esp. since there are a few hill climbs on the way and even in my smallest gear at 100RPM I’m butting out almost 500watts. I usually end up doing 400w something on these couple climbs that take about 7 minutes and my RPM will drop a bit down to 90 something rpm.  So I get to the halfway point in my ride to refill my water bottles and I see that my average speed is almost 21mph average! Normally I do 18-19MPH average even when I’m trying to hammer the whole way. Not only was my average speed higher then ever, it felt easy to do because I wasn’t going anarobic at any point expect maybe for a couple minutes on the one big hill climb.  Only downside was that my butt was noticeably more chaffed, when you pedal that fast for that long you need some seriously good shorts, seat and cham lube or something ahaha.

What I noticed is that by spinning this fast my legs had more momentum, my legs never felt like they where getting bogged down and I was starting to smash. I notice too that my pedal form is better when I spin at high cadence, and when the effort becomes more muscular then cardiovascular I start pedaling in an inefficient mashing style that ignores the hip flexors and lifting and kicking over the top leg muscles. I also noticed that at first it can feel wierd pedaling fater then normal but after a while my legs get use to it and adjust and like it better. The biggest thing I noticed is that I would average a bit slower speed on the flats as I spin and my power would be a little low, normally I would put it in a harder gear and get the speed and power up and the cadence down. But this time I stuck with the 100RPM goal, interestingly every time I’d hit a hill I had a lot more snap and power in my legs and I would spin over it in a fairly big hill and keep my momentum up where before I’d try smashing up it to power over it and my legs would be fried after doing it and I would have to slow way down and let my legs recover.
So I learned that I should  “Rest and recovery and spin on the easy parts, and put in 120% effort on the slow hard parts the hills to keep your speed up” You have the most to gain by doing really well on the inclines. and relaxing a bit more on the flats.

So here is a list of benefits I’ve noticed first hand from riding at higher RPMs

  1. Reserve leg strength and power for hills and sprints where you need it most to power over them and keep momentum up.
  2. Higher RPM makes it easier to have all of your leg muscle groups join in the circular process of pedaling, you’re more efficient at high rpm
  3. It’s easier and surprising at how much more power you can put out spinning faster, or how a high wattage can feel much easier at high RPMs
  4. The cardio system seems to have more capacity and ability to endure then leg muscles, shifting as much of the burden as possible away from the muscular system can be very helpful for some cyclist I believe.
  5. Spinning helps you use the lifting muscles in your legs more to help on the upstroke and kick across the top.
  6. Spinning at a higher RPM helps you pedal easier when you’re going on flats or downhill and recovery, and lets you recover for the next jump or hill climb when you need that leg strength most. Even though it feels very easy and you could pedal harder gears, don’t because it shifts more strain to the leg muscles and takes away their snap for the next hill that is usually just around the corner.  And when that hill or jump comes up you’ll be able to spin a big gear and have the snap you need.
    Even though it’s temping to pedal harder or spin a bigger gear on the flats, it’s best to just spin and let your body rest for a couple minutes before the next roller or hill climb.
  7. Spinning at easy and moderate sections of the rides gets your leg motor units use to firing in a certain sequence that’s more powerful, I notice when I spin on a ride that when I need to jump I tend to do it at faster RPM then usual and it’s easier to do. If I was riding on the flats or downhill sections of the ride in a bigger gear lower RPM, my leg muscles/nerves seem to get use to that pattern and changing RPM dramatically to climb or sprint feels very awkward.  So another benefit of spinning is that your legs are use to the timing the firing pattern and you can spin a moderate gear with lots of power much easier then if you would have been mashing previously.  I usually feel a bit weird at first when I spin at 100RPM or higher, once I warm up after 30 minutes or so my legs start to feel a lot smoother and settle into the cadence.
  8. I also notice that I’m less tired when I do a ride at higher RPM, if I try to hammer on rides at lower RPM I feel wasted at the end of ride from using the muscles more then the heart and lungs.
  9. I notice that higher RPMs make the same wattage feel easier, less anaerobic, less intense and riding fast more enjoyable.
  10. I notice too that I loose more body fat riding more aerobically at higher RPMs
  11. Since I’m not as tired esp. my legs which often are the thing that determine how much rest I need, I can ride more often and require less rest days which means faster improvement faster weight loss and more miles in the bank.
  12. Spinning helps you use more of your legs muscle groups and distribute the load more so they’re less fatigued.
  13. Spinning at higher RPM I believe teaches you to pedal more efficiently.
  14. Spinning makes you ride more efficient and change gears more often, a really good habit for when you hit the hills. If you’re mashing in general, then when you hit the hills you’re probably beyond smashing and grinding slowly away at 50-70RPM which is less then ideal cadence even for mashers I think.
  15. There’s a certain type of momentum you carry up a hill when you spin up and you’re “on top” of the gear vs. fighting to turn over the pedals. I don’t know how to explain this, but going up a hill at 95 or 100RPM vs. a harder gear at my typical 70 something RPM grind, feels like you’re going faster up the hill and able to have less resistance on the up stroke and kick across the top of the pedal stroke, as soon as you slow down everything starts to feel much less efficient. So I think it’s probably critical to keep RPMs up on hills and stay in your power band and optimal muscle firing pattern etc.
  16. Spinning also helps you train  your aerobic system more as you can stress and target it more efficiently. If you mash too much and let the effort be mostly muscular your legs may give out before your heart and lungs.
  17. I have a theory too nothing I can prove easily, but I believe that when you overuse a muscle or group of muscles in your body your heart rate and pattern spike and make you feel very winded and light headed, not because of the stress on the cardio system but because a hard muscular effort triggers body to be flooded with the byproducts of anarobic energy production and you feel really wasted. For example try doing a bunch of pull ups or squats, you’ll be winded and light headed by the time you max out but in a different way then if you where to run a mile at your fastest pace. I think the body bonks when you overload the muscular system, it makes the cardio system to get overwhelmed and over react or something. So if you are pushing your cardio system cycling up a hard hill and then let your RPMs fall to 70RPM and your mashing and and your legs are getting worked really hard then I think it triggers something that quickly puts you in the read zone. If you would simply just spin an easier gear, yes you might breath harder and your heart might feel like it’s working really hard, but surprsingly you can keep pushing the legs don’t bonk out and your heart rate is high but you don’t get that nasty totally wasted feeling and light headed over-reaction like you feel when do a hard muscular effort in the gym. To trigger that effect cycling means slowling way way down to recover. I wish I could explain this better and in scientific terms, but if you lift weights you know the incredablly winded feeling I’m talking about that seems more like an adreal over reaction of the heart and lungs then the real cardio load you’re going through.

    I think cycling hard should feel like running hard, not like doing squats or something, you’ll have that blown up weight lifting cardio reaction before you know it if you try smashing up a hill vs. spinning.

A final word on cadence and riding at a higher RPM

For all the great things I mentioned above, everyone is built different and some people might have weaker legs but better cardio system where a higher cadence works well for them. Where someone else might be built in a way that they can do more by riding a harder gear at a slower rpm to produce the same power, spinning doesn’t work for them, probably because they’re more fast twitch muscle fiber and they need to feel a certain amount of tension in their legs for all the motor units to be trigger to contract efficiently. But it takes months to get efficient at high rpms, at first it will feel very wrong, and your heart rate will be through the roof but over time your heart rate will drop sometimes by 20bpm at the same wattage I’ve read and then spinning feels much more doable. So give spinning a try you may find it really works for you.