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  1. #1
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    climbing - physics question

    Hey all,

    I may or may not be in the minority here, I enjoy climbing. I don't race but like to see the fruits of my labor, and it's enjoyable to FEEL fast going up even if I'm pretty average. Don't get me wrong, descending is a blast.

    A question I've wondered about for awhile now, haven't been able to find an answer to. On a longer climb, is it better to push on the steeper or flatter sections? Where does the extra effort have the most payoff, or is it moot?

    For example, let's say a longish climb is a consistent 5% and I'm pushing a consistent 200 watts. But, on that climb there is one 3% section and another equally long 8% section. If I'm going to increase my output to 250 watts for a set period of time, would the net result be faster if I did that on the 3%, 5%, or 8% sections? Or does it not matter where? Or is the fastest way up to just have your most consistent effort/output?

    My left brain tells me pushing on the flatter parts would yield a higher mph average, but my gut on the trail tells me the opposite. And my inner skeptic wonders if this will just result in an e-bike debate?

  2. #2
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    Coming from a total fat guy who isn't much of a climber, I typically push a higher cadence during the steeper ascents and slow down on the flats to allow my heart rate to recover. This is the only way I can keep from blowing up and not have to stop on a climb like sulphur springs, for example.

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  3. #3
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    If we're talking about what is fastest, it's a math question really: https://en.wikipedia.org/wiki/Amdahl%27s_law . The answer is there is more improvement to be had speeding up the part you spend more time on. So if the steep and not-so-steep drags are the same distance, it makes sense to push on the steep. If they are the same amount of time, you have equal opportunity for improvement in both.

    If we're talking about what's easier, I think it's a personal question. Just consider one factor, rider size: it's easier for me as a light, small guy to go fast on steep uphills than it is on flat. So I ride the climbs that way. If you are a big guy who can put out a lot of power on the flats, conserve your energy on the steep stuff and put the down where it is easy.

  4. #4
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    Hi, I posted a very similar thread a few years back when I was trying to crack the year's record for Mission Peak Stanford side.

    Having rode this trail now for closed to 9 years, here are my tips:

    1. Everyone, including the expert level riders, can only push so much on the steep sections. At the above said hill, this is about 20-25% grade. So you did be wasting your effort trying to push hard here only to fade during the flatter part. I tried, and usually my muscle locked up and I ended up being much slower at the flatter section

    2. The fastest climbers make up time not on the steep, but ride consistently at a respectable speed up the steep stuff. Then, at the flatter section, they explode the flat section while others are slowing down after the steep efforts.


    I experience this regularly trying to outpace the runners at Mission Peak. We are at about the same pace at the steep sections, but as long as I have enough left in the legs to do a moderately fast pace at the flats, this is usually where I pick up the distance that pulls me ahead of them.

    If you care for more tips:

    3. Ride at your own pace. Don't try to chase people down. You will lose all your energy. See point 2 above. Pick up speed on the flatter section to gain distance on people.

    4. When you have a choice, be chased, instead of chasing people. When you are chased, it push you to your absolute limit and helps your strava results.

    5. As much as I am a stand and hammer rider, sitting down has its merits. One of the Filipino guy at Mission Peak that's faster than me taught this very important lesson a while back.

    6. Yes, light weight rider will fly uphill. I used to be that kid. But then I didn't have the muscle to drive the flatter hill section. This will only take you so far, developing the muscle while you remain ultra slim is key.

  5. #5
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    Faster and arguably less energy to accelerate hard, and then try to hold that speed, at any opportunity.

    Considering that drag, such as from tires, a cross-chained drivetrain, and seals, is largely a fixed amount, you have the most to gain by improving your minimum speeds.

    This implies that you should focus effort on the steep part, and also try to shift up quickly and accelerate hard to get up to max sustainable speed on any flatter part.
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  6. #6
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    The fastest way up is to hold the highest wattage you can maintain for the duration of the climb but that's not always viable due to rapidly varying terrain, sometimes it makes more sense to punch it to get over steep rises or technical sections.

    If possible though, hold consistent watts.
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  7. #7
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    See this type of thread is why I come back to MTB NorCal. Please no ebike b/s buzz kill

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    Thanks all for the replies. Does seem like personal preference/strengths would really dictate it to a large degree, and that point about drag and getting up to a sustainable output makes a lot of sense. And yeah, consistency seems like the ultimate goal I guess. That said...

    Hypothetically, if I increase 50 watts on the less-steep section for 5 minutes, I increase my speed there by 2mph (compared to baseline 200 watts). If I increase 50 watts on the steeper section for 5 minutes, I might only increase my speed by 1 mph and for a shorter distance (since my baseline speed is also slower at 200 watts). So wouldn't that give you more bang for your buck on the flatter section of climb? Maybe what Loll's #2 point is getting at?

    I realize this is way-oversimplified (that Amdahl's Law link is beyond me), but wondering if the above premise has some truth to it? Or if I'm missing an embarrassingly obvious flaw. Or perhaps those other variables just have more effect than I'm giving them credit for. Maybe the most obvious answer is I should be riding instead of typing, but this stuff is interesting to me. Thanks again, folks.

  9. #9
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    So there is lots at play here including wind resistance, if the climb in smooth etc. but from a gut feeling I would say that if you are going to crank it for a bit, it would be better to do it on the steeper section. That extra power should translate to more total work being done to get you to the top faster.

    Pushing hard on the flatter section will see you going faster and ultimately loosing more energy to wind resistance.

    The best method would be to ultimately hold a higher sustained power vs spiking.

    Watch when world cup racers and even more obvious road racers attack. It is usually when it is steepest since you donít want that effort wasted in the wind.

    I do have an advanced degree in physics, but as stated there is a ton of stuff in play here (lets not even start on mechanical efficiency of which cog you are in etc). This is just based off a high level look at some of the biggest factors.


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  10. #10
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    This is part physics, part exercise physiology. In general, constant power output is always easier on the body than achieving the same *average* power with high variability.

    Google "normalized power" - which is a metric that tries to quantify this difference. Eg: If you do a very spikey interval, your avg power could be 200W, but normalized could be 250W. What it means is that your body probably feels like it's been holding 250W due to all the spikes, even though the work done was only at 200W.

    Note that this DOES NOT mean that the optimal pacing strategy is to always hold a constant power. The reason for this aerodynamics. You can get a better time by holding higher power on the climbs (speeds are lower and less is wasted to wind resistance) and lower on the descents/flats.

    How much higher and lower? Pro tour teams used to run computer simulations to answer this question - ie. to come up with a best strategy for their TT riders (note that all of this goes out the window in a mass start race because of drafting). bestbikesplit.com tries to offer some of this technology to average joes. If you know your FTP and upload a course elevation profile/ type of bike you are riding (TT vs road makes a big difference) - it'll give you a pacing strategy.

    Having said all that, for slow MTB climbs, the best strategy is almost always going to be using a constant power. The grades are high and speeds too low for aero to be a huge consideration.

  11. #11
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    @ 415mtb, my point #2 is exactly what you are saying. This is based on riding the same climb over and over again for the this long. Attacking at the steep is based on if you have the power. Most of us don't have that power. I used to attack most of the steeps at Mission Peak, but the faster strava time are usually when I hammered at the flat section while maintaining a decent pace at the steep.

    I do respect that everyone is different though. What works for me might work differently for other body built.

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    I usually keep my ebike on lowest power setting in the flatter sections but turn it up to 11 to get up the steeps.

  13. #13
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    Endurance pace on the steeper climbs (unless youíre on a singlespeed, then HAMMER IT), so as to reserve power when you get to the crest as the others you are racing against get off their bikes and are walking them up the last part of the hill. Victory on the climbs, my friends.
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  14. #14
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    Quote Originally Posted by Yeety View Post
    I usually keep my ebike on lowest power setting in the flatter sections but turn it up to 11 to get up the steeps.
    Oh sorry, I didnít realise this was ebr.com forums. Am I in the wrong place???
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    Quote Originally Posted by Leopold Porkstacker View Post
    Endurance pace on the steeper climbs (unless youíre on a singlespeed, then HAMMER IT), so as to reserve power when you get to the crest as the others you are racing against get off their bikes and are walking them up the last part of the hill. Victory on the climbs, my friends.
    That's a good point, if it's a longer climb I keep my bike in endurance mode to make sure I don't run out of juice at the top. I haven't seen many single speed ebikes out there, is that like a CVT?

  16. #16
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    Quote Originally Posted by ssalinas View Post
    See this type of thread is why I come back to MTB NorCal. Please no ebike b/s buzz kill
    Yes! ...whoops, too late. eContent crept in.
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  17. #17
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    I always pass people as they are climbing up hills, I never understand why they are going in that direction.

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    eGads! it's everywhere! You can't escape the emopeds, even online

  19. #19
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    Quote Originally Posted by chuckha62 View Post
    Yes! ...whoops, too late. eContent crept in.
    I donít mind ebikes just the flame wars on mtbr that suck all the oxygen

  20. #20
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    @OP: the rule of thumb in a time trial or a solo attack in a road race is to go hard when its hard. If the road pitches up, you have a headwind, or after having to scrub a lot of speed to maneuver a corner - these are the times to increase the power rather than maintaining a perfectly metered effort.

  21. #21
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    This is such a cool thread. I love climbing too, and I've spent years trying to figure out how to get to the top of the hill faster. It's such a kickass mental challenge.

    For me, the fastest strategy is to maintain my heart rate at all costs (160-165bpm) since I don't have a power meter. That is roughly what I can sustain for an hour or more.

    I've found that my tendency is to push through the steeper stuff - at the expense of heart rate - and recover on the flats or less steep sections. This is not fast. It may work for some, but the small amount gained at high heart rate comes at great cost to my speed on the flatter sections, as well as later in the climb.

    And if I do "burn a match" and punch up through 170bpm, I have found that I can recover just as quickly at, say, a 165bpm pace as a 150bpm pace, so I've trained my brain to not let off the gassl too much and recover at the higher pace. The heart rate will come down and I continue to put out good power while waiting for it, as opposed to wobbling along at a super low speed.

    Man, I need a power meter.



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  22. #22
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    Wouldn't a constant power, and therefore fluctuating speeds depending on grade, the fastest way up?

    Admittedly, I am a crappy climber and have no clue.

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  23. #23
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    Climbing sux!!

    It's a necessary evil, to get to the gold.

    NB, I'm referring to what OP mentioned - long grinder climbs w/ steep parts.

    Now... technical challenges (climbs) are my jam!!

    I love getting up techy climbs while others are walking, dabbing, falling(?)!!

    Unfortunately, where I live there aren't too many techy climbs 😭

    One of my favorite trails (climb) had 6 quite techy sections.

    After I separated my right shoulder 3 years back. I went back to ride the same trail & it had been neutered!? 🤬

    I almost cried... 🥺

    Just over a year ago, they built a steep, gnarly decent at the top 😍

    All was forgiven.

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  24. #24
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    IMO, it's complicated by variations in the terrain. Like cars going around a track, the fastest apex depends on what's past the corner. The strategy for climbing on a mtb would have to include that info. Grade reversals, tech sections, and extremely steep sections that require high output would need to be accounted for. If you're familiar with the trail you can intuitively optimize your efforts to a degree, I'm sure everyone is familiar with that.

    I agree the ideal is a constant power output, but if you can achieve that on a mt bike you need to be riding more difficult trails.

  25. #25
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    The answer is: it depends.

    If the low-grade portions are shallow enough that wind resistance becomes a factor at higher effort levels, it might be best to meter your effort on those sections. You will be putting out effort for minimal gain compared to a lower power effort.

    Then, you can go harder on the steeper sections.

    If the climb is steep and steeper, the opposite is true. A more consistent effort would be better.

    And, all of that depends on the individual in question. If my 98lb/45kg wife is doing 250w up a low grade climb, she's going to be encountering wind resistance. A 250lb dude doing 250w up the same climb is, uh, not.
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    If the discussion is about fire road uphill time trial, I would argue the most important thing is to gear your bike such that your power and cadence can be maintained reasonably at the steepest portion. Then, math and money can get you the strategy per coarse.


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    Super interesting topic and Iím learning a lot. Thanks all!

  28. #28
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    What do you mean by long-ish? On a <15 minute climb, you will likely be faster going hard on steep sections, making sure to power over the top to carry speed into the flatter portions. On any sections where the speed is >10mph, wind resistance starts to ramp up (exponentially, as it does), though not hugely noticeable until 15+ mph.

    At the pro level, there's actually a lot of drafting on some mountain bike courses, for example, at the Bonelli Park ProXCT or Sea Otter. For example, in my best ever Sea Otter result, I finished 20th and averaged 16.6 mph, and went up the 3% average grade Skyline Road dirt climb in a small pack at over 15mph!

    But if the climb has no sections under 5% grade or your average speed is under 10mph with no flat sections over 15 mph, you are almost certainly limited by physiology, not wind resistance. It is well established that for any effort over 4 minutes long, an even or slightly "negative split" will yield the highest average speed. For a single effort under 10 minutes, you may be faster punching it at the beginning and end, because you may be a fast-twitch type rider with a decent reserve of anaerobic speed once you can see the light at the end of the tunnel, regardless of how winded you are in the aerobic-limited middle portion.
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  29. #29
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    I've never had a powermeter on a mtb, but I do have one on my gravel bike.

    For contrast, compare these two segments. Both were all out efforts and are/were KOMs at the time. Let me know if you need a paid Strava account to view my links, and I'll screenshot and post them here.

    1. Up Dogmeat, 13:43, 413w average. Super spikey power, some 0w time on the short downhills, crazy low cadence (64) because that climb sucks and I was on my gravel bike in 34:36 gearing the whole time. Even with all that suckiness and a slow flat with thirty seconds to go, I averaged 450w for the last minute. For me, this climb was short enough to recruit some serious anaerobic power at the start and end.

    2. The big climb at Lost and Found 2018, 41 minutes, 354w average. I rode all but four guys off my wheel just by tapping out the tempo at a very consistent power and cadence (94). Some people went ahead early, then I passed them and never saw them again. Unlike Dogmeat, I would've popped like the rest had I gone anaerobic at any point on the climb.
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  30. #30
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    In my original question, I think I really undervalued air resistance. I've heard that above 9-10 mph, the dominant force of resistance is aerodynamic - rather than gravity, trail/tire friction, mechanical resistance, etc. Maybe this number is for road riding, but that general idea really lends itself to expending those harder efforts on the steeps. But yeah, all so relative and dependent on the person, route and day. By feel, I agree with the approach of endurance efforts on the steeps, but topping out strong on those sections and keeping up the intensity as it flattens out. Kind of like those "over/under" cycling workouts. In a lab, I imagine the strictly consistent output would be the best approach, but I think there's also some psychological advantage to topping out strong and maintaining. I'm not racing, so not necessarily to create a gap with another rider (though I'm sure that's effective too) but more just to keep that mental drive going, keeping an aggressive mind set, and breaking the climb into chunks. I wonder if the "go hard when it gets hard" approach is partly for the psych effect.

    I'm also thinking it's a lot harder to modulate power output when it gets real steep. I don't have a power meter but I imagine on a 20% grade it's a lot trickier to nail exactly x number of watts than it'd be on a 5% grade. So you may inadvertently burn some matches there.

    Thanks for all the solid insights, I like to geek out on stuff like this. Even... er, especially when there's no clear, simple answer!

  31. #31
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    Quote Originally Posted by Menso View Post
    What do you mean by long-ish?
    Didn't have a specific one in mind, but right now I'm thinking of a 45-60 minute climb and two others that take me about 20 minutes. Since techy climbs have so many other factors, I was just considering the fire road scenario. Like Railroad Grade on Tam.

    Makes sense the approach would be different on those two climbs you link. That's some serious output!

    (As an aside, you gave me some great trail info on Mt. Eddy climb back in September - thanks for that - a great day on the bike.)

  32. #32
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    For anything that long, physiologically you absolutely need to do your best to do even efforts. Building the psychological side is difficult and takes practice- both mentally and physically, it doesn't make sense to do frequent 30-60 minute efforts. You will get much more effective adaptation from doing rides with multiple 12-20 minute climbs summing up to 60-90 minutes of climbing, provided you hit all those climbs with minimal recovery and at the same power you would be doing for a theoretical one-off 30-60 minute time trial effort. Here is an example (road bike) workout from when I was still racing. 12ish minute climb + 4x an 18ish minute climb at high zone 3 to low zone 4. 377w, 376, 377, 376, 376. Consistency is king.


    On the Mt Tam Railroad climb, I happen to be good friends with the guy who has the KOM
    . He's a really talented climber and descender who I informally coached while he was in college, and he also made his way to being a good cat 1 roadie, so he knows how to spin it steady. His effort on the railroad grade is good example of going out too hard for a 30+ minute climb. He still got the KOM, but he pointed out that he started too hard in his ride description. You can see where he realized it about 9 minutes into the effort, and settled down into a much more consistent power and cadence output.
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    I love this thread. And cool to get Menso chiming in!

    As a power meter nerd I can say for sure that nearly everyone backs off their power effort significantly when grades mellow on MTB's. Folks with a road background are better about this but almost everyone does it.

    I think the answer to climbing fast over long climbs is steady effort but I think you will notice the most immediate bang for buck in your times "speeding up" in the flats. I put that in quotes as its more about maintaining the same power output in the flats as on the hills. It does usually feel harder as putting out power in the flats is harder for most of us.
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    If you don't feel the blood in your lungs and some stomach contents working its way up you're doing it wrong

  35. #35
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    Quote Originally Posted by oliver37 View Post
    This is such a cool thread. I love climbing too, and I've spent years trying to figure out how to get to the top of the hill faster. It's such a kickass mental challenge.

    For me, the fastest strategy is to maintain my heart rate at all costs (160-165bpm) since I don't have a power meter. That is roughly what I can sustain for an hour or more.

    I've found that my tendency is to push through the steeper stuff - at the expense of heart rate - and recover on the flats or less steep sections. This is not fast. It may work for some, but the small amount gained at high heart rate comes at great cost to my speed on the flatter sections, as well as later in the climb.

    And if I do "burn a match" and punch up through 170bpm, I have found that I can recover just as quickly at, say, a 165bpm pace as a 150bpm pace, so I've trained my brain to not let off the gassl too much and recover at the higher pace. The heart rate will come down and I continue to put out good power while waiting for it, as opposed to wobbling along at a super low speed.

    Man, I need a power meter.



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  36. #36
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    climbing at a consistent power output at your LT is fast but it would be faster if you could burst above your LT for some period of time. luckily you can do this but you will need some time to recover. so for the best time you would want to ride at LT or slightly below while recovering and then burst your power above that level as much as possible. you could theoretically do this at any time regardless of the terrain but in practice its much easier to push hard while its steep and much more difficult to ride at a recovery pace while its steep. so you want to push hard on the steeps and recover on the flats

  37. #37
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    I have zero doubt that maintaining constant power is the slowest way to climb. It's like believing that a constant slope going downhill is faster than one that drops down steeply then gradually levels out.

    Using a burst to accelerate quickly, getting into a few gears higher than you might think would be comfortable, and trying hold that gear with a sustainable power output spinning smooth circles at an efficient RPM, raises the average speed with minimal extra total energy spent (to reach the summit). If you develop habits of doing this you can recover much quicker from the bursts of hard acceleration and you'll pass people on climbs regularly, and be able to maintain this pattern on longer 1hr+ climbs.

    Regarding it being a math problem, you can apply the concepts of the the brachistochrone, which implies that a certain amount of hard accelerating before switching to sustaining takes the least amount of time with the same amount of energy. You're after improving your average speed, to reduce the time it takes to climb, without taking excessive energy, are you not? The drag issue is another issue that can be sort of seen mathematically--tire drag is constant while air drag increases as you speed up. At 4 mph, the tire drag might account for wasting 40% of your power (60W, with you putting out 150W), while at 8 mph it might account for wasting only 25% (60W of 240W), and at 16 mph it might account for wasting 15% (60W of 400W), but air drag might account for wasting 20% of your power at 16 mph and only 5% at 8 mph**. Do you want to minimize the waste out of consideration of your energy levels to endure the long climbs?

    **I pulled these #s outta my ass, but they're calculated guesses based on feel. Cross-chained drivetrain also a significant source of drag.
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  38. #38
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    Iím not up on all the watts, power, etc. but I did start using Strava for the first time a few weeks ago.

    The trails I ride are mostly flat, with a few short, steep climbs. I noticed looking at my Strava times that as an old, fat guy the climbs are where I could improve the most. I could haul butt as fast as I could on the flats and the very gradual downhill sections and still only improve my time on those sections by 5 seconds or so. Besides, Iíd likely crash into a tree if I went any faster.

    However, I noticed that if I really put in a decent effort (with proper momentum and gear selection) I could power up those short, steep climbs and improve my time by 10-20 seconds or more on each section. I ended up cutting over a minute from my lap times just by hitting the climbs hard and riding at steady pace the rest of the time instead of crawling up the climbs in granny gear and then trying to make up time on the flat sections.

    Thatís just me, though. I havenít really ridden much in the past twenty years and Iíve just gotten back into it starting in March. Iím having a lot of fun.


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    I know your question is about hill climbing in general but it correlates pretty well to general KOM hunting. The rule of thumbs on KOMs is push it hard on the easier sections. Couple of reasons for this:

    - You will carry more speed into the harder sections. When this comes to KOMs my philosophy is hit the actual trigger start time at a max sprint lol.

    - Everyone struggles on the "hard sections", you may lose a few seconds/mins (relative to length obviously) at most.

    - If you max your HR out on the hard sections you will need to recover and that will cause an overall letdown of performance on the easier sections. When it comes to maxing out your HR, your body will force you to recover.

    - If its a long "hard" section, break it down into relative "easier" and "harder" sections within the overall hard section. Gun it on the "easier" sections of the hard segment if that makes sense.

    - Always push it hard on the DHs, fast times always are the fastest on the DHs.

    - Human nature is to relax when it gets "easy". Pushing yourself through those "easy" sections by mentally whipping yourself pays big dividends because most people really struggle with this.

    - The classic example of this is called riding through the hill on rolling hills in an Ironman. You can make up huge time by gunning / sprinting the last few meters of a climb, through the crown and then sprinting the initial DH. Why? Because once again human nature is to ease up as you see the top, use the crown to recover, then let gravity accelerate you. Overriding this normal behavior really helps you cut into time in an almost free way.

    Sorry probably a little bit off topic and off base for the question. It's just what came out when I started typing, lol!
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    I'm not a great climber, like swimming, my body type wants to go straight to the bottom and stay there. But, one experiment I did a while back really helped me on long hard climbs. I measured my heart rate on a climb during regular ride where my HR gets up to 170bpm, and then did the same climb trying to keep my heart rate under 150bpm by continually reminding myself to relax all parts of my body and spin. My times weren't that much different. I was wasting so much energy by being tense and muscling the climb. I instantly became far more efficient on climbs. I'm now going faster uphill and with much less effort than before by using this idea during climbs.

    Another thing I use is a technique I learned back in my wrestling days called diaphragmatic breathing.

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    Quote Originally Posted by roughster View Post
    I know your question is about hill climbing in general but it correlates pretty well to general KOM hunting. The rule of thumbs on KOMs is push it hard on the easier sections. Couple of reasons for this:

    - You will carry more speed into the harder sections. When this comes to KOMs my philosophy is hit the actual trigger start time at a max sprint lol.

    - Everyone struggles on the "hard sections", you may lose a few seconds/mins (relative to length obviously) at most.

    - If you max your HR out on the hard sections you will need to recover and that will cause an overall letdown of performance on the easier sections. When it comes to maxing out your HR, your body will force you to recover.

    - If its a long "hard" section, break it down into relative "easier" and "harder" sections within the overall hard section. Gun it on the "easier" sections of the hard segment if that makes sense.

    - Always push it hard on the DHs, fast times always are the fastest on the DHs.

    - Human nature is to relax when it gets "easy". Pushing yourself through those "easy" sections by mentally whipping yourself pays big dividends because most people really struggle with this.

    - The classic example of this is called riding through the hill on rolling hills in an Ironman. You can make up huge time by gunning / sprinting the last few meters of a climb, through the crown and then sprinting the initial DH. Why? Because once again human nature is to ease up as you see the top, use the crown to recover, then let gravity accelerate you. Overriding this normal behavior really helps you cut into time in an almost free way.

    Sorry probably a little bit off topic and off base for the question. It's just what came out when I started typing, lol!
    That's not how it works in the real world, for actual climbing.

    Going hard on a 2% section doesn't result in much appreciable momentum into a 10% section than pushing significantly easier and traveling slightly slower. An increase in power to the pedals will NOT result in a linear increase in speed, unless you're going pretty slow. And, acknowledging the physiological toll, it means that you'll be spending MORE time going slower on the steep portion of the climb. Which is exactly what you don't want.

    Whereas an increase in effort on a steep section will result in a nearly-linear increase in speed.
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    ^ In other words, there's severe diminishing returns on your increased effort on flatter/easier sections, while there is virtually no diminishing returns from increased effort on steep climbs.

    I believe it's quite the opposite with steep climbs, with there being huge gains to be had where a 25% increase in effort can get way more than 25% increase in speed, especially if you're not the most fit; maybe even a doubling of speed with 25% increase in power, if you're normally going like 3-4 mph up steeps. I'm guessing Le Duke's fitness is high enough to the point where he sees this bonus has leveled off to be linear.
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    Quote Originally Posted by Le Duke View Post
    That's not how it works in the real world, for actual climbing.

    Going hard on a 2% section doesn't result in much appreciable momentum into a 10% section than pushing significantly easier and traveling slightly slower. An increase in power to the pedals will NOT result in a linear increase in speed, unless you're going pretty slow. And, acknowledging the physiological toll, it means that you'll be spending MORE time going slower on the steep portion of the climb. Which is exactly what you don't want.

    Whereas an increase in effort on a steep section will result in a nearly-linear increase in speed.
    I understand your point but also think your example is also not real world considering the real world aka actually how trails are built. A hard section isnít a 10% grade. Most sections that are considered hard would be short and punchy and >20%. Too boot, MTB trails are rarely if ever featureless and furthermore the steeper it is usually the more featured it gets. These type of climbs donít equal linear power to progress because of the needed finesse and line choice, power output at features, required turning etc. all of these things reduce the effectiveness of just applying more power. If your 10% sections are hard, itís because they are super featured, not necessarily requiring just raw straight line power.

    If we were talking paved road climbs, Iíd be 100% with you, but were not. Also, you mention ďslow speedsĒ. The average MTBer is going slow speeds and will see a mentally driven effort on flats and DHs aka the easier sections yield faster times. You may be talking ultra fit amateurs / pros on a they have wired, then I would lean a little more towards your thoughts, but generically applied to real trails and normal MTBers, Iíll stick with my assessment.

    edit: rereading the OP he is calling 8% a ďhardĒ section which really reaffirms my thought he has room for improvement on the easier sections and most likely general fitness is where he will see the biggest gain unless those climbs are also technical in which case raw straight line power returns are once again diminished.
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    Quote Originally Posted by Varaxis View Post
    I have zero doubt that maintaining constant power is the slowest way to climb.


    Zero doubt? I think it depends on the climb. If it's fairly steady one the consensus seems to be that holding the max power you're capable of for the duration of the climb is generally fastest. KOM hunters are well aquatinted with this technique and watch their power meters to make sure they don't go into the red zone. Doing bursts above threshold will have to be paid for later.

    Of course this doesn't work with all climbs, techy ones and trails that are severely undulating are a different deal.
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    Quote Originally Posted by roughster View Post
    rereading the OP he is calling 8% a ďhardĒ section
    Nope. Re-reread.

    This already complex question becomes virtually impossible if you consider tech features, truly steep pitches, momentum carry, wind/aero, an individual athlete's physiology, tire pressure, e-bike battery life, moon phases, beet juice consumption hence the oversimplified fire road scenario.

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    Quote Originally Posted by J.B. Weld View Post
    Zero doubt? I think it depends on the climb. If it's fairly steady one the consensus seems to be that holding the max power you're capable of for the duration of the climb is generally fastest. KOM hunters are well aquatinted with this technique and watch their power meters to make sure they don't go into the red zone. Doing bursts above threshold will have to be paid for later.

    Of course this doesn't work with all climbs, techy ones and trails that are severely undulating are a different deal.
    You're arguing for efficiency through training. If one trains steady state all day, everyday, they become way more efficient at that specific style. They'll crush on any long steady sustained efforts. The addition of a power meter ensures that they don't underestimate, nor overestimate their effort level, to set a good baseline to beat. Add undulating terrain where it's difficult to maintain steady effort without skillful shifting; add technical challenges, and they can't take advantage of their training. You're pointing out that style's main weakness, one that the burst method is well adapted to.

    Adding short bursts, besides being mathematically faster, is arguably more efficient in other ways, such as keeping you engaged to keep from regressing to sloppy technique. It takes a different training approach to make it so these short bursts are nothing to pay for, recovering in no time.
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    Quote Originally Posted by roughster View Post
    I know your question is about hill climbing in general but it correlates pretty well to general KOM hunting. The rule of thumbs on KOMs is push it hard on the easier sections. Couple of reasons for this:

    - You will carry more speed into the harder sections. When this comes to KOMs my philosophy is hit the actual trigger start time at a max sprint lol.

    - Everyone struggles on the "hard sections", you may lose a few seconds/mins (relative to length obviously) at most.

    - If you max your HR out on the hard sections you will need to recover and that will cause an overall letdown of performance on the easier sections. When it comes to maxing out your HR, your body will force you to recover.

    - If its a long "hard" section, break it down into relative "easier" and "harder" sections within the overall hard section. Gun it on the "easier" sections of the hard segment if that makes sense.

    - Always push it hard on the DHs, fast times always are the fastest on the DHs.

    - Human nature is to relax when it gets "easy". Pushing yourself through those "easy" sections by mentally whipping yourself pays big dividends because most people really struggle with this.

    - The classic example of this is called riding through the hill on rolling hills in an Ironman. You can make up huge time by gunning / sprinting the last few meters of a climb, through the crown and then sprinting the initial DH. Why? Because once again human nature is to ease up as you see the top, use the crown to recover, then let gravity accelerate you. Overriding this normal behavior really helps you cut into time in an almost free way.

    Sorry probably a little bit off topic and off base for the question. It's just what came out when I started typing, lol!
    Contrast these answers with mine and realize that basically everything stated above is not how this works. If it did, I've been doing everything wrong over 14 years of professional road and mtb racing.

    Bottom line: make your effort as even as possible, don't "gun it" anywhere and don't "max out" your hearth rate anywhere except the beginning and end, and DON'T push it hard on the downhills. You will save seconds but not recover your HR for the aerobic climbing to come.
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    Quote Originally Posted by etuck View Post
    You totally need a power meter. You would love it!
    I am sure I would! There's even a nice crankshaft-integrated model for my RaceFace cranks. But $500 has been hard to accept.

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    There's a reason why pro road cycling attacks come on the hills, and not the flats. Of course drafting comes into play somewhat (in that it's harder to drop someone on the flats with raw power when they can hang on to your wheel), but in general if you have extra watts to expend you get a bigger benefit to spend them when you're going slower already, uphill, because less of the extra energy is wasted fighting air resistance and rolling resistance.

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    Quote Originally Posted by nilswalk View Post
    There's a reason why pro road cycling attacks come on the hills, and not the flats. Of course drafting comes into play somewhat (in that it's harder to drop someone on the flats with raw power when they can hang on to your wheel), but in general if you have extra watts to expend you get a bigger benefit to spend them when you're going slower already, uphill, because less of the extra energy is wasted fighting air resistance and rolling resistance.
    Somewhat to do with drafting.. lol It has everything to do with drafting!

    The other side of the coin is you'll never ever see any pro hammer the hills on a TT or a triathlon stage. Think about that..

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    Okay if we are talking over-simplified fire road scenario then Iím out. I was talking about training experience and real world from winning my Age Group at Full Vineman, coming in 8th overall and coming in 12th overall at Dick Collins Firetrails 50 mile Ultramarathon, since weíre flexing Menso ... I guess pro experience is the ONLY experience that counts.

    and just to be clear .. I said AVOID maxing out your HR, and I am talking about a segment (KOM) not a whole fíing race, lol.

    Also, reread the post you quoted, we actually agreed on a quite a bit.
    Quote Originally Posted by menso
    ...making sure to power over the top to carry speed into the flatter portions.
    Also
    Quote Originally Posted by menso
    For a single effort under 10 minutes, you may be faster punching it at the beginning and end, because you may be a fast-twitch type rider with a decent reserve of anaerobic speed once you can see the light at the end of the tunnel

    Also,
    Quote Originally Posted by menso
    ...but if the climb has no sections under 5% grade or your average speed is under 10mph with no flat sections over 15 mph, you are almost certainly limited by physiology
    But clearly you're carrying over from the ebike thread, so obviously yours is the only perspective to consider so carry on!
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    Quote Originally Posted by ananth View Post
    Somewhat to do with drafting.. lol It has everything to do with drafting!

    The other side of the coin is you'll never ever see any pro hammer the hills on a TT or a triathlon stage. Think about that..
    Uh, what?

    You couldnít be more incorrect.

    Thatís where the difference in made in every hilly TT.


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    Quote Originally Posted by nilswalk View Post
    There's a reason why pro road cycling attacks come on the hills, and not the flats.


    Plenty of attacks happen on flat roads in pro races.
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    Quote Originally Posted by Le Duke View Post
    Uh, what?

    You couldnít be more incorrect.

    Thatís where the difference in made in every hilly TT.


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    Well here's some actual data.

    https://www.trainingpeaks.com/blog/2...file-analysis/

    Difference between avg and normalized power is barely 5%, which indicates a very consistent effort. For most amateurs, even on a flat course, that kind of consistency is hard to achieve. If you have ever ridden with a power meter, you'd know how hard it is to get those 2 numbers that close.. you'd have to be constantly looking down at your head unit.

    And this is top level pro putting 2x the power most people on this board are. So speeds are much higher, and aero is much greater consideration for him. If you use bestbikesplit.com for your FTP, the variation in power suggested will be even lower.

    He went < 15% harder on a short 2.5 min 10% climb.. maybe you want to call that hammering?

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    Quote Originally Posted by Varaxis View Post
    You're arguing for efficiency through training. If one trains steady state all day, everyday, they become way more efficient at that specific style. They'll crush on any long steady sustained efforts. The addition of a power meter ensures that they don't underestimate, nor overestimate their effort level, to set a good baseline to beat. Add undulating terrain where it's difficult to maintain steady effort without skillful shifting; add technical challenges, and they can't take advantage of their training. You're pointing out that style's main weakness, one that the burst method is well adapted to.

    Adding short bursts, besides being mathematically faster, is arguably more efficient in other ways, such as keeping you engaged to keep from regressing to sloppy technique. It takes a different training approach to make it so these short bursts are nothing to pay for, recovering in no time.




    Disagree. Power bursts aren't mathematically faster. Hill climb segments are essentially time trials and time trials are won by athletes who are good at holding their threshold power.
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    My conclusion is steady power as much as possible. Cresting a hill with steady power can feel like a wattage bump just due to the increase in speed, AND that's where I would spice things up if I'm going to. Also to add - I think austink26 was getting at this - the better way to think about it is climbing feet per minute (or some other rate of vertical movement) rather than (sloped) miles per hour.

    @ananth, thanks for that Training Peaks link - good stuff.

    The fastest riders I've known are guys who take an inquisitive rather than dogmatic approach to their craft. @roughster - if the scenario/question isn't up to your standards, I have no problem with that. Have fun out there.

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    Quote Originally Posted by 415mtb View Post
    @roughster - if the scenario/question isn't up to your standards, I have no problem with that. Have fun out there.
    I just am not all that in to theory craft when the level of experience here indicates we all understand reality. We donít need to debate a fire road scenario as the training science is pretty clear for a smooth / featureless relatively gradual incline.

    What I think the op was looking for, and maybe I read it wrong and he was looking for a theory craft discussion, was how do I get faster on a real MTB climb with sections of varying difficulty using grade as a baseline unit of measure but not necessarily ignoring reality.

    The answer to that question for 99% of MTBers is easily answered. The most bang for your buck is get more fit and the next most effective means of getting faster is ruthlessly wire the technical features / harder sections to minimize the required output.
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    Interesting thread! I havenít read all the replies yet, but dipped out and did a Google search.

    If you really want to nerd out on this, you could probably find what youíre looking for here:

    https://www.gribble.org/cycling/power_v_speed.html


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    Quote Originally Posted by 415mtb View Post
    My conclusion is steady power as much as possible. Cresting a hill with steady power can feel like a wattage bump just due to the increase in speed, AND that's where I would spice things up if I'm going to. Also to add - I think austink26 was getting at this - the better way to think about it is climbing feet per minute (or some other rate of vertical movement) rather than (sloped) miles per hour.

    @ananth, thanks for that Training Peaks link - good stuff.

    The fastest riders I've known are guys who take an inquisitive rather than dogmatic approach to their craft. @roughster - if the scenario/question isn't up to your standards, I have no problem with that. Have fun out there.
    If you have a bike computer it should be able to display VAM (an acronym, in French, for vertical speed) while you ride. It relies on your speed + altitude change to calculate a reading, so there is about a 5 second lag, but it's still useful to build a frame of reference.

    For me, on an MTB, I can cruise along at 700 VAM for a long time, but can't sustain 1,000 for too long. Super fit tour riders can sustain 1,500+ on a road bike, which is nuts.

    VAM is pretty highly correlated to heart rate / power before drag factors into the equation, as discussed in this thread, but it's still a nice way to normalize for slope.

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    Quote Originally Posted by J.B. Weld View Post
    Plenty of attacks happen on flat roads in pro races.
    Yes I know. Most of them though are due to the peloton getting complacent and people trying to catch them napping. i.e. tactical reasons, rather than it being the ideal time from a physical advantage standpoint.

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    Good topic with good discussion. Especially appreciate insights from those with actual data.

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    Quote Originally Posted by nilswalk View Post
    Yes I know. Most of them though are due to the peloton getting complacent and people trying to catch them napping. i.e. tactical reasons, rather than it being the ideal time from a physical advantage standpoint.


    Crosswinds can be an ideal place to attack from a physical advantage standpoint.
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    Quote Originally Posted by AlexB_510 View Post
    Interesting thread! I havenít read all the replies yet, but dipped out and did a Google search.

    If you really want to nerd out on this, you could probably find what youíre looking for here:

    https://www.gribble.org/cycling/power_v_speed.html


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    Over simplified calculation there. The simulation can be improved if they took more factors into consideration regarding drag.

    Drivetrain losses immediately strikes me as inaccurate. There's less frictional losses with a chain under greater tension, with the chain going around larger diameter cogs/chainrings/pulleys, with less cross-chaining. At least one of the IHPVA newsletters has good data supporting this, with it counterintuitively showing a pattern that frictional losses decrease with greater power output.

    Tire hysteresis is reduced by increased torque, higher tire material temp (up to a point), and higher tire ride height. They have it doubling with a doubling of speed, which in general makes sense due to it being tied to wheel RPM, but it doesn't take these factors into consideration. Crr seems less severe at higher speeds, especially off-road, since it doesn't feel like it is sinking and getting hung up. A tire is always sort of riding uphill, due to the amount of load compressing it and the amount it is compressing the ground. You likely notice this most when riding soft soils like sand, where the terrain immediately in front of the tire is sloped like a hill. It's also why higher pressures are generally faster on hard well-traveled surfaces (narrower tires on hardpack, esp if you have susp), and low pressures work better on less traveled surfaces (plus/fat tires running under 18psi in the backcountry or on actual gravel). Higher torque raises the tire ride height.

    Trying to apply even power across a pedal stroke, spinning smooth circles, applies constant torque that reduces tire drag and some chain friction losses. There's also hypermiling techniques, like getting acceleration out of the way quickly, rather than slowly accelerating up to an equilibrium that matches your cruising power output.

    Climbs can be time trials in a way, but why does that imply that you should not attack parts of it, and merely use some KISS method of putting out constant power? While I, and seemingly others like mensa, advocate for short bursts, we're implying:
    - increase power before entering a steeper section to carry a lot of inertia into it
    - increase power as soon as you exit a steeper section, to minimize time lost due to slow acceleration on the flatter part
    - put down power while you still have a clear opportunity to, to minimize stalling on any obstacles on the straighter and simpler line

    Also interesting to note is something called "planing", that might relate to the trend of stiffer-is-faster/better and how it might affect power output: https://www.renehersecycles.com/the-...cs-of-planing/ (implies that some flex at the BB might be a good thing)
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    Good thread.

    I ride a lot and think I know what Iím doing. My instinct tells me to hammer the steeper parts to maintain momentum and minimize time spent on the harder section, hammer into a steep climb to build momentum, etc.

    Itís all wrong. The best speed on a long climb is actually achieved (for most climbs) by consistent effort with a push at the end if going for best time (as opposed to racing, when you always want to leave some strength to accelerate on the flat after the climb).

    I ride often with a pro MTB racer. He laughs at me for how uneven my power is, my habit of pointless accelerations etc. He tries to help me tame my instincts so I can learn to ride stronger for longer. Bottom line: what Menso and a few others say above is correct.


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    For consideration:
    At Octoberís Ironman World Championship, a group of researchers from the University of Connecticut studied how various types of pacing can affect overall performance. The results of their study, which were recently published in the Journal of Science and Medicine in Sport, showed that how you tackle the up and downhill sections of a race may be the most important predictor of performance.

    Led by University of Wyomingís Evan Johnson, Ph.D., researchers took a random sampling of Hawaii-qualifying athletes and measured their predicted personal pre-race goal time against their finishing time on race day. Using Timex Ironman Global Trainers and TrainingPeaks software, they analyzed nine segments of the bike course and 11 segments of the run course.

    Their goal was to determine whether any of the segments predicted performance, and they were surprised at the resultsóthe downhill portions (on both the bike and run) proved to be most influential on overall time.1 They found that athletes who maintained faster relative speeds on the downhill sections of the course, and who had smaller changes in heart rate between consecutive up and downhills2, were more successful relative to their goal times.

    On average, all participants went 10 percent faster than their goal bike pace on the 15-mile downhill section back from Hawi. The difference was that the top thirdóthose who finished within 7 percent of their goal timeówent 14 percent faster on this section, while the bottom third only went five percent faster. ďThis shows that those who did best overall used the downhill to maximize velocity and not for recovery,Ē Johnson says.3
    From:
    https://www.triathlete.com/training/...ls-triathlons/

    I highlighted three spots in that article from the study:

    #1- Pushing / gunning it (this does not mean maxing your HR out!) on the DHs is the most effective predictor of performance. That's from the study for both run and bike.

    #2- Pushing / gunning it (this does not mean maxing your HR out!) on the DHs does not mean not applying more effort. As I mentioned above, natural human reaction to the top of a hill / initial DH is to relax as in reduce effort. Pushing/gunning it at the last bit helps maintain effort / HR and avoid a decline in effort, not necessarily meaning an above "target" exertion.

    #3 - DHs are not for recovery, you must "push" through the DHs to fight the natural instinct to use the free speed from gravity, which without the rider providing power, will result in slowing down.

    I guess some people have been doing it wrong all these years according to the article.
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  67. #67
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    I thought this was supposed to be about climbing.

  68. #68
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    Quote Originally Posted by Loll View Post
    Hi, I posted a very similar thread a few years back when I was trying to crack the year's record for Mission Peak Stanford side.

    Having rode this trail now for closed to 9 years, here are my tips:

    1. Everyone, including the expert level riders, can only push so much on the steep sections. At the above said hill, this is about 20-25% grade. So you did be wasting your effort trying to push hard here only to fade during the flatter part. I tried, and usually my muscle locked up and I ended up being much slower at the flatter section

    2. The fastest climbers make up time not on the steep, but ride consistently at a respectable speed up the steep stuff. Then, at the flatter section, they explode the flat section while others are slowing down after the steep efforts.


    I experience this regularly trying to outpace the runners at Mission Peak. We are at about the same pace at the steep sections, but as long as I have enough left in the legs to do a moderately fast pace at the flats, this is usually where I pick up the distance that pulls me ahead of them.

    If you care for more tips:

    3. Ride at your own pace. Don't try to chase people down. You will lose all your energy. See point 2 above. Pick up speed on the flatter section to gain distance on people.

    4. When you have a choice, be chased, instead of chasing people. When you are chased, it push you to your absolute limit and helps your strava results.

    5. As much as I am a stand and hammer rider, sitting down has its merits. One of the Filipino guy at Mission Peak that's faster than me taught this very important lesson a while back.

    6. Yes, light weight rider will fly uphill. I used to be that kid. But then I didn't have the muscle to drive the flatter hill section. This will only take you so far, developing the muscle while you remain ultra slim is key.
    Wow, great advice. I got nuthin to add.
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  69. #69
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    Quote Originally Posted by Train Wreck View Post
    I thought this was supposed to be about climbing.
    It is when applied to reality. All climbs can be broken into mini-segments. Each mini-segment will have a relative difficulty due to grade and/or technical features.

    The fundamental theory I was proposing is push it on the easier sections (which on some climbs also includes flat/mini-DH section(s)) to avoid the reduced effort that is human nature when reaching these "easier" segments. DON'T blow up your HR on the steeper / harder sections as that's where you will suffer catastrophic time loss as a result of your body forcing you to recover while not making that much difference in overall time.

    The study showed you need to mentally whip yourself (push) on the easier sections in order to maintain the consistent output and not use easier sections to recover. Hence why the consistent grade / featureless fireroad scenario is kind of, meh. You are not trying to account for fluctuation in power needs based upon the "trail" and therefore the answer is simply: just apply even power.
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  70. #70
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    Hello STRAVA!

    Seriously, this is precisely the function it was made to perform.
    It works for climbing as well as descending, ya know.

    After (each) ride you add notes on how you performed on each section, and you will have all the data needed.

    You correlate how each exertion schema left you (subjectively) feeling, with the actual performance outputted (time, speed, dist, vert dist), and determine what is most efficient.

    Am I missing something?
    This is either a good thing, or a very bad thing.

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    I feel like I gain on people that have a similar pace as me by simply adding a lot of speed & getting in to a higher gear quickly at the start of an easy section and maintaining it over that length.
    Personally I run closer to my max HR just trying to keep up on the climbs. My opinion is that most people take it too easy on the flatter sections figuring that they are going fast enough but traveling 2 mph faster over a long stretch makes a big difference.

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    Last edited by Suns_PSD; 3 Weeks Ago at 09:07 AM.

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