|
|
Thread Tools | Display Modes |
#31
|
|||
|
|||
More distance per Calorie: Walk vrs Granny Gear Uphill?
So isn't it actually more efficient energy use to walk uphill than to pedal, even if you do have unimaginably low gears and no topple-over on a trike? The legs walking up will be a lot more efficient in tranferring the power to make forward progress, so I'd assume walking would be the most energy efficient way. Over to the physicists. Alan. Alan, you are forgetting that the cyclist will be wearing cleated shoes. I walked up a hill once with these shoes and soon had other problems besides the hill. Pat in TX |
Ads |
#32
|
|||
|
|||
More distance per Calorie: Walk vrs Granny Gear Uphill?
"Artemisia" wrote in message
oups.com... On 7 sep, 14:37, "Clive George" wrote: But more importantly with the trike you've got something you can't do on any bike : stop and sit there. So you pedal until you're puffed, put the brakes on (with locking device/velcro as appropriate) and sit there relaxing, coz you can. Ah, but on the bike I just hop off , you see. When I get huffed, I stop by the roadside, standing and visible. It's easy to walk the bike along with me. Whereas that becomes a lot harder with the trike. So overall, the hill may be easier with the bike, insofar as it's a walk, with stops whenever needed. Yes, pushing the trike isn't good. So you don't do it. It's a different approach - rather than walking, you stop, relax, then ride again. Or indeed ride _really_ slowly - which you can, because there's no need for balancing. I'm trying to figure out if the trike is an advantage or an unnecessary bother on the morning commute. I think the only way you'll find it out is by trying it. I reckon the trike will be less efficient than the bike, but other factors may make it more effective for you. cheers, clive |
#33
|
|||
|
|||
More distance per Calorie: Walk vrs Granny Gear Uphill?
|
#34
|
|||
|
|||
More distance per Calorie: Walk vrs Granny Gear Uphill?
Artemisia wrote in news:1189176557.361981.144840
@r34g2000hsd.googlegroups.com: I should mention that in the case of my particular hill, there's no grass; its all smooth tarmac. Its just dark and windey and infernally steep and there are cars on it. You can tell how steep it is by how much the cars are stinking - I get practically asphyxiated whenever I'm passed by one. You need one of these: http://www.egopt.co.uk/ Users report double takes from people as they pedal seemingly effortlessly up steep hills -- Tony " I would never die for my beliefs because I might be wrong." Bertrand Russell |
#35
|
|||
|
|||
More distance per Calorie: Walk vrs Granny Gear Uphill?
On 7 Sep, 13:44, "
wrote: On Sep 6, 7:09 pm, Artemisia wrote: Peter Clinch wrote: I recall one incident when a pal and I were taking our MTBs up a fairly steep grassy field. I got bored at walking pace, and decided I'd walk. While walking, I soon overtook my pal, still spinning happily in 1st... So isn't it actually more efficient energy use to walk uphill than to pedal, even if you do have unimaginably low gears and no topple-over on a trike? I'm thinking perhaps the only advantage of trying to pedal up my hills is the inconvenience of trying to stand up out of a recumbent... EFR Ile de France Cycling (particularly on a recumbent!) is not a weight bearing exercise like walking. That is to say, cycling up a hill requires you to only move your center of mass up the slope, not carry it. When you carry something up a hill you need to not only move it up the slope, you need to support it's weight the whole time too. Think about carrying rocks up a hill with a wheelbarrow vs a backpack. When cycling the center of mass stays pretty still and thus follows the slope of the hill without too much extra energy spent. Walking makes the center of mass bob up and down a bit which uses energy that cycling doesn't. Cycling has the added weight of the bike, and the resistance of the drivetrain, rolling resistance, and wind resistance, but in terms of calories per distance at slow speeds where wind and rolling resistance are minimal, cycling will always be more efficient. At high speeds where the exponential wind resistance is much greater, one needs to expend a lot more energy to overcome this resistance, and then walking is more efficient in terms of calories per distance. A lot slower too! Now in the case of a steep hill with grass and thus relatively high rolling resistance, it may be that the increased rolling resistance more than makes up for the difference of cycling not being a weight bearing exercise. Gearing and what is a comfortable range of cadence and force generation for the leg muscles comes into play too. If you try pushing someone on a bike on a flat feild of grass you can see how much resistance there is. And since it seems that riding up this hill vs walking was more or less a wash despite the extra rolling resistance, this suggests to me that cycling is that much easier than walking by the same amount of effort it took to push the person on the grass. (That made sense to me at least...) Joseph cycling up steep hills is less efficient than walking.ive seen many mountain bikers riding,legs spinning round,hardly moving,whilst walking i have also passed bikers on the mountains.ive even seen cyclists in very low gear on the road,in too low a gear,legs going round like mad,hardly moving,very innefficient,one turn on my gear on a racing bike leaves them standing.i think some of them dont want to put any hard effort into cycling.ive also seen bikers on low gear dawdling along,no physical effort being used,they cant be benifiting physicaly in fitness riding that slow.god forbid if they ended up on a hill on a cycle track. |
#36
|
|||
|
|||
More distance per Calorie: Walk vrs Granny Gear Uphill?
gary2006uk wrote in
oups.com: cycling up steep hills is less efficient than walking.ive seen many mountain bikers riding,legs spinning round,hardly moving,whilst walking i have also passed bikers on the mountains.ive even seen cyclists in very low gear on the road,in too low a gear,legs going round like mad,hardly moving,very innefficient,one turn on my gear on a racing bike leaves them standing.i think some of them dont want to put any hard effort into cycling.ive also seen bikers on low gear dawdling along,no physical effort being used,they cant be benifiting physicaly in fitness riding that slow.god forbid if they ended up on a hill on a cycle track. You've mixed up lots of things that have nothing to do with efficiency and some that do and you have the wrong way round. For example spinning quickly is more, not less, efficient than your "one turn on my gear". Speed has nothing to do with efficiency unless you are starting to go fast enough to introduce air resistance. Those fast spinning cyclists you deride are probably getting up that hill far more efficiently than your wasteful technique. -- Tony " I would never die for my beliefs because I might be wrong." Bertrand Russell |
#37
|
|||
|
|||
More distance per Calorie: Walk vrs Granny Gear Uphill?
Tony Raven wrote:
Artemisia wrote in news:1189175506.087339.182640 @d55g2000hsg.googlegroups.com: On 7 sep, 15:28, Peter Clinch wrote: Which is what I've supposed all along, but do you want to get the top of the hill in the most optimally energy efficient way, or the most subjectively /comfortable/ way right there and then? I, and I suspect Artemesia, and the majority of other cyclists will prefer the most subjectively comfortable way, even if it's slower. And especially if it's quicker. Exactly - I guess I didn't phrase my initial question correctly. I should say, for the same speed and distance uphill, which will get me less out of breathe, walking or cycling? For me walking because I can walk more slowly than I can cycle. It will take longer and use more energy but I will be less out of breath doing it. But she says "at the same speed". It's still not a black and white answer, because your muscles aren't all working in a common pool in a precisely similar way between the two modes so it's not just a case of working out the energy needed. There will be times when walking will work better, and there are times when cycling will work better. Variables include the hill, the wind, your tiredness, how fast you can hit the bottom of the hill, how gung-ho you feel at the time, and so on. Pete. -- Peter Clinch Medical Physics IT Officer Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital Fax 44 1382 640177 Dundee DD1 9SY Scotland UK net http://www.dundee.ac.uk/~pjclinch/ |
#38
|
|||
|
|||
More distance per Calorie: Walk vrs Granny Gear Uphill?
Tony Raven wrote:
gary2006uk wrote in oups.com: cycling up steep hills is less efficient than walking.ive seen many mountain bikers riding,legs spinning round,hardly moving,whilst walking i have also passed bikers on the mountains.ive even seen cyclists in very low gear on the road,in too low a gear,legs going round like mad,hardly moving,very innefficient,one turn on my gear on a racing bike leaves them standing.i think some of them dont want to put any hard effort into cycling.ive also seen bikers on low gear dawdling along,no physical effort being used,they cant be benifiting physicaly in fitness riding that slow.god forbid if they ended up on a hill on a cycle track. You've mixed up lots of things that have nothing to do with efficiency and some that do and you have the wrong way round. For example spinning quickly is more, not less, efficient than your "one turn on my gear". Speed has nothing to do with efficiency unless you are starting to go fast enough to introduce air resistance. Those fast spinning cyclists you deride are probably getting up that hill far more efficiently than your wasteful technique. I think that when the gear becomes really low, the effort of rotating the legs many times over a short distance becomes significant. Whereas with walking, the stride length is not decreased very much. Julian Gallop |
#39
|
|||
|
|||
More distance per Calorie: Walk vrs Granny Gear Uphill?
Peter Clinch wrote in
: For me walking because I can walk more slowly than I can cycle. It will take longer and use more energy but I will be less out of breath doing it. But she says "at the same speed". That's another reason - I'd fall off cycling at the speed I would walk ;-) -- Tony " I would never die for my beliefs because I might be wrong." Bertrand Russell |
#40
|
|||
|
|||
More distance per Calorie: Walk vrs Granny Gear Uphill?
On Sep 7, 10:25 pm, Tony Raven wrote:
" wrote groups.com: The first obvious omission is the weight of the bicycle (as you admit below) which is a significant penalty for the cyclist, However if you are walking with the bicycle you still have to lift its weight up the elevation so that drops out the equation. It only matters if the choice is between walking up the hill without the bicycle vs cycling up the hill with. I really find it hard to believe that an intelligent and experienced off-road cyclist could seriously dispute that in the situation as described, it may indeed be more energy efficient to walk. According to measurements done by Schwalbe using SRM power cranks on a 500m uphill grade a gravel surface increases the power needed by ~30% and a grass meadow increased it by ~80%, depending on tyre width and pressure, so still probably well inside the walking efficiency. [For safety adds caveats of boggy ground, ground littered with big boulders etc etc] Why do you think this is well inside the walking efficiency? I have already said that there are lots of caveats I omitted to my original response to Artemesia's post starting this thread (46e03452$0$7753 ). Knowing Artemesia's cycling styles from her posting history here I doubt very much that any of the scenarios being posted to attack my original answer are of any relevance to her cycling. I'm happy to agree that on a proper road surface, riding up a steep hill is likely to be clearly more efficient than pushing a bicycle (and even walking without a bicycle, at least usually). Off-road, it depends heavily on the conditions, and if the conditions are soft enough (or slippery, something else we haven't mentioned) for walkers to actually be overtaking cyclists then I think it is reasonable to assume the reverse. I think most people who ride off-road in the UK have encountered such situations. Your claim "Cycling is a more efficient way of moving than walking so cycling up will use less energy" is clearly false as a general statement, and although it might seem picky to demand every detailed caveat, the post it was replying to specifically described a situation where it is at least possible, and perhaps likely, to be false. Worse, you repeated the assertion in response to the specific question "Is cycling more efficient than walking under all circumstances?" thus apparently indicating that there were no caveats (other than the weight of the bicycle, which as you are now keen to point out is not relevant to walking v pushing)... James |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
How small can you go? (granny gear w/ STI) | kevinkiller | Techniques | 22 | October 2nd 05 04:28 AM |
won't shift to granny | Kyle.B.H. | Techniques | 12 | May 5th 05 03:32 PM |
Granny vs. the hill | Dave | Techniques | 10 | October 1st 04 05:50 AM |
Granny gear on my road bike | Lance | Australia | 1 | September 10th 04 03:19 PM |
Ahhh, a granny gear for the weak of leg and lung. | Jonesy | Mountain Biking | 5 | May 21st 04 03:37 AM |