Road Cycling - Downhill riding vs. Climbing vs. Flat

Is there a muscular and physiological difference between riding on flat, downhill and uphill? I am 5'7 and 151 (16 years old, male) and I kill people on the uphill but when I descend, my heart rate explodes and I run out of energy. Are the muscles used to bike downhill different? Is it because I normally push myself on the uphill and slack off on the descents? :rolleyes: :confused:

There should be no physiological difference in terms of muscles used, except for the obvious difference between sitting and standing (which you are likely to vary more when climbing).

You obviously have a climber's build, which greatly helps you when climbing. It means, of course, that a heavier cyclist will beat you on the descents, however.

I am not sure why your heart rate should "explode" when descending. There is an interesting argument for saving energy on a descent. Since Air resistance becomes huge at the speeds encountered in a descent, a cyclist has to exert a lot to make even small differences in speed. Check out the following: www.sportsci.org/encyc/cyclingupdown/ cyclingupdown.html

Cheers,
Jamie

Originally posted by jmlee
Check out the following: www.sportsci.org/encyc/cyclingupdown/ cyclingupdown.html

Cheers,
Jamie

Great article - thanX for the link!!!! :D

Thanks guys (and/or gals), I didn't know if there were other people like me. I stay seated when climbing 95-99% of the time unless sprinting. I have short legs and am surprised that I am looked at as physiologically a climber since I have a rather heavy stock at 151 being only 5'7".

Any other responses will be great.
Thanks.

I would think of 151 and 5'7'' as still pretty light in the grand scheme of things. But, you are still young. You will likely fill out in the next 5-8 years with more weight and height. (I am 140 and 5'8", at 34 years; at your age I was same height, but just 128 lbs. Needless to say, I did well at the hill climbs.)

But, the important thing is your strength weight ratio. If you increase the former as you fill out, you'll have no problem remaining a good climber.

If anyone wants to see how the equations which Sloan uses work in practice, I have set up an excel sheet which models the equations. You may download it here: www.uni-bonn.de/~jmlee. Look for the "wattage calculation" link.

Cheers,
Jamie

I kill people on the uphill but when I descend, my heart rate explodes and I run out of energy. Are the muscles used to bike downhill different? Is it because I normally push myself on the uphill and slack off on the descents?

fujimo,

hmm... the part about heart-rate exploding on the descent strikes me as odd...

i'm not too sure about the physics and all - but i can tell you that in a group of "similar" cyclists (like in a race) i excell on the climbs (especially short steep ones), sprints and downhills, while i am gasping for air just trying not to get dropped on flats... for me i think it has to do with a bunch of things: i am fairly light (6'1", 165lbs) with very high fast-twitch muscle "sprint" strength, but my disadvantgae is inefficiency. on sprints and climbs my strength to weight ratio is good, but i am not very efficient... so on flats where efficiency (both cardio, energy/digestion, and pedalling technique) is more important than strength and strength/weight is irrelevant -- i am not so fast for a like group. i think of the analogy of an auto engine: a big racing engine has more power but is very inefficient so with restricted fuel supply over a longer distance, a small efficient vehicle can outperform a big engine vehicle despite the fact that the big engine would destory the little one in a "drag race".

if you are meaning flats or slight downhills then i think the answer is "yes"

but if you truly mean downhills where you can attain high speeds without even pedalling much i think there may be something else like a mechanical/technical problem if you get dropped on a descent --- is your tire pressure too low or do you not have a high enough gear and spin out??

to be very general, there are 3 major strengths in cycling: climbers, sprinters or pacers (forgot the official name here):: and usually each person has a strength, a weakness and an "ok" area

** climbers - usually light with good power to weight ratio
** sprinters - usually strong but especially have fast-twitch muscle fibers ---- they tire out easily
** pacers - are very efficient and usually excel at time-trials

for example, i am first a sprinter, 2nd a climber and 3rd a pacer: i can sprint with anyone as long as i get to rest afterwards and i never get dropped on a "jump" or a short hill --- but my danger is burning out or getting dropped during the sustained parts... i had a good trainer partner for a few years and in races (mountain bike or road criteriums although he'd beat me in TimeTrials) and any time (except when i was tanked) i could outsprint him (cycling and running too) but on the long flats i would struggle to not get dropped while riding in his wind shadow! he was super-efficient while i had the power but no efficiency!

learn what your strengths are, train to minimize your weakness and then race with your strenght in mind (e.g. in a criterium IF i can make it to the last sprint with the front group i will win or come very close - but i have to pace myself and not blow-up too soon)

I usually fall apart when I am in my drops, on a descent between 2-4% downhill grade. Maybe I am compressing my diaphragm too much.

I pulled this quote from the link above. I think I'm really beginning to understand now. Check it out:

"As a consequence of scaling geometry, mass increases with the cube of height, while surface area only increases with the square of height. This means that, although larger cyclists have a greater total frontal area to push through the air than smaller cyclists, their advantage in mass (and power generating capacity) is even greater. As a consequence, large cyclists have a higher ratio of power to frontal area than smaller cyclists, giving large cyclists an advantage in overcoming air resistance, as observed in time trials. It is not surprising that Miguel Indurain, the pre-eminent time trialist of the 1990's, was larger than most of his rivals."

I would say it is a matter of conditon. On a dh situation you muscles used may be the same but they are used in a isometric way. This is a unique way of building muscle and is very different from edurance based training. Imagine comparing cross training to power lifting. Power lifters get exhausted doing anything that requires distance and constand movement and repetive motion while they can explode using a different cell combination. Cross trainers try for higher reps using lower weight. Throw them in a power lifting situation doing heavy set of deadlifts/squats etc...they will become exhuasted.

The only way to truly know what your muscles are good at is to do a muscle biopsy. Of course the constant training and knowing what you are good at is just as good for the experienced athlete.

Myself. I am a power freak. Short spurts uphill, or long dowhills where strength is required are my strengths. While I can handle long uphills it is a lot of work for my muscular type.

Dumb question...

Can you rule out the uphill ride as a reason for your exhaustion on the flipside coming down?

BK

Do you mean to ask does the exhuastion received from riding uphill not affect downhill. It is still affected. I am still burned. My aerobic level would be shot but my legs are strong. On the way down my muscles and anaerobic take the rest of the beating. By the time I would be done my legs would be sore (coming down) and my aerobic/cardio would be shot. :)