I found this nugget on nsmb.com http://nsmb.com/trail_tales/dhstudy_summary_06_06.php, and it has so many variables, I cannot believe they are trying to pass it off as an objective study....
Downhill Physiology Study
- Thread starter sanjuro
- Start date
We were talking about that sort of thing at the last race. At the Super Sunday race, they ran the XC guys up the beginner DH course while the Expert class DH was on the second run (combined times).
As the XC guys crossed the finish, most were hardly winded while the DH guys would fall off the bike. Based on this reaction of a 6 minute ride vs. a 90 minute ride, one could say the DH guys are out of shape when compared.
But when I was talking to one of the DH guys who used to race XC, he told me he used about 80% effort and energy when racing XC where as DH was a lot closer to 100%.
Not to say this study is acurate, but I would tend to agree with the overall ideas presented.
As the XC guys crossed the finish, most were hardly winded while the DH guys would fall off the bike. Based on this reaction of a 6 minute ride vs. a 90 minute ride, one could say the DH guys are out of shape when compared.
But when I was talking to one of the DH guys who used to race XC, he told me he used about 80% effort and energy when racing XC where as DH was a lot closer to 100%.
Not to say this study is acurate, but I would tend to agree with the overall ideas presented.
I saw that and thought it was pretty whacky.
My heart rate increases when I watch porn or horror flicks. Does that mean I can gain fitness by sitting on the couch?
My heart rate increases when I watch porn or horror flicks. Does that mean I can gain fitness by sitting on the couch?
than why am i still fat.:mumble:
i think some of that is true. i just went downhilling, and my forearms are KILLING me. you get a goot workout. but i think adreniline has alot to do with it.
here is an example. if you play a wicked intense videogame.. like tom clancies ghost recon. your about to win. your heath is depleted. your openents heath is depeleted. you have one shot to take him out. its you or him.( keep in mind the most physical action your getting is moving your thumbs.) your heart rate is WAY above what it would be if you where just sitting there doing nothing. its the scary factor. its the.. "oh **** if i do this wrong i hit a tree going 15 MPH". not the physical aspect.
i still think XC is way harder. but there is no doubt in my mind DH is hard physicaly too.
i think some of that is true. i just went downhilling, and my forearms are KILLING me. you get a goot workout. but i think adreniline has alot to do with it.
here is an example. if you play a wicked intense videogame.. like tom clancies ghost recon. your about to win. your heath is depleted. your openents heath is depeleted. you have one shot to take him out. its you or him.( keep in mind the most physical action your getting is moving your thumbs.) your heart rate is WAY above what it would be if you where just sitting there doing nothing. its the scary factor. its the.. "oh **** if i do this wrong i hit a tree going 15 MPH". not the physical aspect.
i still think XC is way harder. but there is no doubt in my mind DH is hard physicaly too.
Well, this is like comparing sprinters vs marathon runners. While a sprinter might exert 100% for a short period of time, I bet he has plenty left in the tank for 2-3 more heats. A marathon runner might be only at 80% but I bet after 2 hours, he has nothing left.jimmydean said:
You might see some dhers puking after their runs, but I doubt they have drained ever bit of energy from their bodies.
Sure, riding downhill is as effective as riding uphill for fitness. What kind of drivel is this?
well its two totally different types of exercise. XC envolves more endurance not as muscle tone (like DH) but in constant riding. After a sweet pumpin run on the dh coarse it would be totally different than on a XC one. there is a type of muscle tone in peoples bodies but i forget what they are...but it is true
The study is referring to fitness, which is normally cardiovascular fitness.
You are referring to fast and slow twitch muscle fibers, which has nothing to do with it. Fast twicth muscle fibers are what make some people born sprinters and others born marathoners. Fitness plays little to no part in developing these.
You are referring to fast and slow twitch muscle fibers, which has nothing to do with it. Fast twicth muscle fibers are what make some people born sprinters and others born marathoners. Fitness plays little to no part in developing these.
Not as much muscle tone? The XC rider would most likely have better muscular development. XC riders use a mix of fibres (fast and slow twitch fibres) to power their bike. An endurance athlete will have a predominance of slow twitch fibres which are long running aerobic fibres. For quick bursts of energy, fast twitch fibres are also recruited, which are anaerobic and quickly fatigued.kahner89 said:
I'd suspect if muscle biopsies were taken of a DH rider and an XC rider, you'd find a higher fast twitch fibre count in the DH rider. This would explain their extreme exhaustion at the end of a run. The XC rider would likely have a greater slow twitch count, indicative of endurace training.
Of course, that could only be a piece of the puzzle. You also have the CV system's ability to feed all those muscles. With a more highly developed CV system, you'll have an increased ability to rely on slow twitch fibres and leave fast twitch to be recruited when lots of power is necessary.
Adrenaline (as mentioned earlier) has a definite inotropic effect as well.
Pedaling constantly (as most XCers do, not all DHers do) will also vastly increase the venous return to the heart. By the Frank Starling law, the increased return will cause a stronger heart contraction, forcing more blood out into systemic circulation. The increased stroke volume of the heart allows the heart speed to remain more constant versus someone who does not use legs as much.
And further, I would think a DH rider would be doing a lot more isometric-like contractions with their muscles (I don't know, I've never downhilled) which would wear on fast twitch fibres, causing an extreme feeling of fatigue.
SJ is completely right, there's SO many variable, and SO unreliable a method of taking data, that it almost shouldn't be published. It doesn't take an exercise physiologist to know that.
Where have I heard that before? Oh yeah it was youZark said:
. I may still be new to all this, but I know my last downhill run made me feel like I had just run a marathon. 
There was a LOT of physical exertion. But as Zark constantly reminds me, HT and XC will get me in shape for the DH. Now if I can just get back on the horse 
Mostly, I am criticizing the test, not the riders. I would think a better test would give the 10 riders the same bike (or two tests with a xc and a dh bike), power meters on all bikes, as well as HR and cyclometers, and compare that.robdamanii said:
Well, I'm not criticizing the riders either (at least I hope it didn't come across that way), but there's a lot of different things they don't account for. I was just trying to think through what they didn't provide for, at least that I saw.sanjuro said:
I completely agree though, they need better methods of collecting data. Maybe VO2 info would be useful, RPE, HR, BP, EKG etc etc. That would be a much better way of handing things. One kind of data (just HR) is completely ridiculous.
ill give you guys my 2 cense.
dh IMO is harder since you have a heavier bike(usually) and you are riding obstacles and rocks and everything..(wait i know this is dumb, but does being scared when your heart speeds up, could that affect your heart rate?) if so, when you get sketchy on a landing or riding something difficult, my heart is racing, so that could be a huge variable..
for XC wouldn't it just take a lot of stamina and endurance to get uphill?
-with downhill you need to manuvere(sp?) at a faster rate and more then going uphill? aren't you learning back, pedalling agreesively and bouncing around a lot more?
idk but that is what it sounds like to me..there are tons of variables like you said, but thats my opinion on the hardness..but ig uess it is how people adapt to what they ride..i mean, a dh rider won't go uphill as fast as a XC rider and an Xc rider won't make it down the mountain faster then a dh rider provided with the proper bike too..idk
dh IMO is harder since you have a heavier bike(usually) and you are riding obstacles and rocks and everything..(wait i know this is dumb, but does being scared when your heart speeds up, could that affect your heart rate?) if so, when you get sketchy on a landing or riding something difficult, my heart is racing, so that could be a huge variable..
for XC wouldn't it just take a lot of stamina and endurance to get uphill?
-with downhill you need to manuvere(sp?) at a faster rate and more then going uphill? aren't you learning back, pedalling agreesively and bouncing around a lot more?
idk but that is what it sounds like to me..there are tons of variables like you said, but thats my opinion on the hardness..but ig uess it is how people adapt to what they ride..i mean, a dh rider won't go uphill as fast as a XC rider and an Xc rider won't make it down the mountain faster then a dh rider provided with the proper bike too..idk
You have to be fit and strong for downhill to run it effectively just as you have to be fit for XC to run at long distance cardio rides effectively. You do have to be stronger to throw your bike around and be in the right position on the bike. Versus when you're focusing on climbing and stamina you need that cardio fitness, along with mental strength and focus.
That's why i love mountain trail riding because you mix elements of both....
That's why i love mountain trail riding because you mix elements of both....
I see lots of fat XC guys and lots of fat DH guys.
What's the point?
What's the point?
This is lke comparing apples to oranges. While dh racers need an overall fitness base, their workouts need to be overall shorter and more intense compared to their XC compatriots (this is why I like riding xc on my singlespeed - besides making it higher in the skill factor on hardtail, it makes the ride more like an overall sprint rather than a spin). Hence it's like comparing training for a sprinter versus a marathon runner, as said before in this thread. Yeah, they both run but their training is tailored quite differently.
Yep. I've had this dicussion for years and it's the biggest difference betwen XC and DH: Riding XC will improve your XC fitness. However, just riding DH will not improve DH fitness. You can improve you DH skills but eventually you'll reach a plateau where your skill equals your fitness level and you cannot improve. So if you really want to get faster, you'll need to train in other ways. See Sanjay's recent thread. For years it seems he more or less got by on his natural talent (better than I'd ever be no matter how much I trained), but now that he's started training, he's improved even more.Jim Mac said:
A good comparison is American football. You need to be fit to play football at a competitive level, but just playing football will not make you fit. Riding/racing DH is similar.
I think the comparison between sprinters and marathon runners is about right. It has less to do with fast and slow twitch fibers and more to do with anaerobic and aerobic. A downhilll run ,at least a race run, is a full out sprint for like four minutes where a xc race is more towards ninety. The recovery time for the dh is much faster, but the exhaution is more intense right after completing the run. There is also the mental factor of having to focus all of your mental engery completely for four minutes, you cant zone out for a second in a dh run, where an xc race you can just spin up a hill and kill yourself but your mind can be somewhere else for the most part. I used to be really tired at the end of intense baseball games (and im no fat baseball player) just from paying attention for 3 hours straight, it was the same feeling as after taking a final or the act/sat.
How many of you making comments have raced both XC & DH?
Unless you have, wouldnt you be just guessing at some of this stuff
Unless you have, wouldnt you be just guessing at some of this stuff
Fast vs. slow twitch fibres is the same thing as aerobic vs. anaerobic.erastusboy said:
I think you're really on to something discussing concentration though.
erastusboy said:
I have done a handfull of 24 hour (team, not solo!) xc races over the years and have gotten in to DH racing as of last year, and from my limited experience you are right on the money with the mental factor. I remember havnig the ability to zone out for a few seconds on some xc races. I zoned out at Mt. Snow last year at a DH race and killed myself on slick roots. DH racing in my humble opinion has a higher necessity for mental focus and energy, at least concentrated in a tight time period.
If you're racing xc you bust a nut over the course of hours, if you're racing dh you bust a nut over the course of minutes. either way you've busted a nut.
I guess it's somewhat similar to that picture that keeps popping up... where is that picture anyways? Oh yea! here it is:
As for the dude that said the study should probably not be published... the journal and reviewers will decide that... if reviewed properly the journal will not publish without sufficient detail on the study limitations. If it gets through review without the limitations discussed as necessary then it is more a fault of the process than the author. Kudos for the author to try to incorporate research into something they love.
I guess it's somewhat similar to that picture that keeps popping up... where is that picture anyways? Oh yea! here it is:
As for the dude that said the study should probably not be published... the journal and reviewers will decide that... if reviewed properly the journal will not publish without sufficient detail on the study limitations. If it gets through review without the limitations discussed as necessary then it is more a fault of the process than the author. Kudos for the author to try to incorporate research into something they love.
You like fat guys?blue said:
It was not published in a peer-reviewed journal, it was published in an e-zine on some website somewhere. The data was flawed, and that's my main problem with it.HOOWAH said: