As far as increasing speed or distance, I think it probably depends on your goals- if you’re looking to run a marathon, you worry more about the distance, since your real goal is going to be to complete the race, whereas if you’re looking to run a 5k, you’re going to want to try to increase your speed earlier. If you’re just looking at general fitness, I’d increase distance first on the theory that you’re less likely to get injured if you keep your pace controlled as a beginner. Just remember to get enough recovery (don’t run 7 days a week as a beginner), and don’t increase distance by more than 5-10% per week. Oh, and make sure you have decent running shoes if you’re going to run very much. I believe www.runnersworld.com might help you out.
Conventional wisdom has it that a Paved Road is “Faster” than a Dirt track, and the treadmill surface is generally at least as forgiving as dirt trail. They’re probably right about wind resistance- although I believe that actually varies with speed doesn’t it ? So Completely IMHO, you might not notice too much difference with like a 5mph jog on a treadmill versus a road, but a runner who could easily run at the treadmills maximum speed (12 mph on the treadmills at my gym) might find the treadmill enormously easier.
SlowmindThinking, do you have a link to anything about that study ? Was the treadmill uniformly easier from a brisk walk through a fast run, or did you just test it at one constant speed ?
slowmindthinkingThe heating effect from being indoors is a good point that I have never thought of. The cooler your body and muscles are, the higher your performance is, drastically. Wind and breeze can make a huge difference from a small room with only a ceiling fan.
I guess I wasn’t completely clear. The study for which I was a guinea pig involved using a particular stride and testing to see if it improved our efficiency based on measures such as speed at lactic threshold, etc. The efficiency measurements were taken on a treadmill so that they could draw blood at regular intervals, so that we could breathe through a regulator for air flow measurements, etc. I asked about the researcher about the differences between running outdoors and on a treadmill, and he told me about various studies investigating just that, so I don’t have a link to that. I’m not sure my study is on-line, either. One cool aspect of the study was that I got to pick up a few studies on serious athletes, such as oxygen use (VO2 max) of different kinds of athletes.
The best answer I can give you is to try and run into a 5 mph wind, which is just faster than a brisk walking pace. You will notice the difference in effort. When you run into a 5 mph headwind, at 5 mph, you are facing the same headwind I get doing 6 minute miles in calm air. Since 10 mph breezes really aren’t much, even a slow runner can occassionally run into a 15 mph headwind! I’ve actually run in winds, perpendicular to my direction, high enough to make it noticeably harder to breathe.
The force of friction due to air should be linearly proportional to the rate at which the air flows by. So twice the wind, twice the resistence.
I’d like to, but then I look at the speeds at which some world class athlete runs, and I know I couldn’t use such a name. Thw world record men are running quarter miles in under 75 seconds. Over one hundred consecutively! :eek: It is always more honest to claim to be slow.
Or at least, less glycogen per mile at a given speed.
Well, as a runner gets better trained, they will tend to have a higher capacity to take in oxygen, combined with a better efficiency (as you note above). However, efficiency varies greatly, even among highly trained athletes - athletes with the same VO2max can have wildly different running performances.
There’s also evidence that trained endurance athletes are better able to use fats as a source of fuel - useful, when the glycogen starts getting thin on the ground.
I think what matters is the degree to which your footstrike is elastic. A treadmill is softer than the dirt out here in the western US, but treadmills have always seemed “springier”, so I think there is actually less energy loss per step.
Soreness from running has two causes, not including the types of motion that induce actual injuries. One is the jolt from your footstrike. One of the good things about running is it strengthens your weight bearing joints. One of the bad things about running is that it does this by wacking the crap out of your joints. That is why even a fit person should not increase their mileage by more than 10% a week.
The other cause is muscle soreness that accompanies many forms of exercise. I find that the drinks designed specifically for recovery work great. They all have about the same carb-protein ratio, one that has been shown to effectively minimize recovery time.
I run marathons (4:23 at best) and have an engineering degree, so I guess I’m qualified to weigh in. Over time, I estimate I run about 50% of my mileage outdoors, about 30% on a treadmill, and about 20% on non-running activities.
As most people have said, running on a treadmill is a bit easier than outdoors. However, I think the difference is trivial with regard to any “normal” training goals. The differences in energy burned can easily be made up by adjusting your incline (if that’s possible) or using heart rate as a guide.
Having said that, I know my recent best time for 5k on a treadmill is 24:00, and outdoors, in race conditions, I best I can do is 25:55. I’d say that’s a significant difference, but I could attribute it to elevation changes, caution (looking out for potholes, loose gravel, etc.) turns, and maybe interaction with other racers. I believe that you can push yourself harder (if you have a mind to) on a treadmill than outdoors because of the controlled conditions.
Having said that, I also know that in sub-maximal situations, if I try to match my perception of intensity while running outdoors with a recent treadmill effort, I’ll almost always end up running faster outdoors than on the treadmill. This is especially true for distances beyond 3 miles or so. I think the effect is more psycological than physical, however.
So, whenever I make the choice between treadmill and road, I generally don’t worry about comparing the effort. I just go with whichever one is more convienient for that day’s run.
1% incline is usually quoted as the value to equalise for wind resistance. Mined ewe, this won’t be quite the same - the biomechanics of running up a slight incline versus into a headwind are bound to differ a tad.
These ‘interactions’ with the environment are good points. Other issues could be, (i) the treadmill may not be correctly calibrated, (ii) if the treadmill motor isn’t so well controlled, it may speed up somewhat when you are no longer in contact with the belt (and slow down a smidgeon when you come back down to earth). In this way, a ‘bouncy’ running style might lead to overestimations of true running speed.
FWIW (which isn’t a lot), I used to be able to sustain c.6min/mile over 10miles on the roads, but on a treadmill I would only be able to sustain this pace for a couple of miles. I think either the treadmills I used were out of whack, or perhaps the world needed recalibration.
Actually, no. The square law holds for many things, but not people at running speeds. At least I’ve been told that. I could dig around and try to find an explanation when I’m not at work.
(For those that are interested, resistance when moving through a fluid medium, and air counts as a fluid, is often modeled as the product of a term based on the moving object’s geometry and construction, multiplied by a simple power of the object’s speed within the fluid. However, like all approximations, there are regimes within which the approximation holds and regimes within which it doesn’t.)
Time yourself outdoors someplace with no potholes. You’ll still be faster on a treadmill, at least for distances for which overheating and psychological aspects don’t come in to play. For example, I can run sets of 400m at better than 75s, if I find a treadmill fast enough. Outdoors on a rubberized track, I’m doing good to hit them at 80s. (The track I use is at 6200 ft, so it’s not like I’m not trying.) On a treadmill watching TV, I can comfortably do a 10K at better than a 6 minute/mile pace, with no taper, etc. Outdoors, I have to be racing to hit that pace for that distance.
All that said, a treadmill can be tremendous use for exercise. It gets you used to running faster, and it can be great for training your body to handle heat. The woman who represented the US at the Olympics in the marathon lived in Alaska. She knew the qualifying race was in S. Carolina, so she trained on a treadmill. Everyone else blew up, but she did fine.
Medically, your heart rate is NOT a very good indicator for the number of calories you burn. I refer you to Cardiovascular Physiology, by Morhrman and Heller (pp. 155-161 in my old 1986 edition).
Avoiding the math, in acute exercise the heart rate increases, but so does the arterial blood pressure (and the pulse pressure), venous return and vasoconstriction. All of these factors affect cardiac output, which is proportional to the amount of oxygen you burn (via the Fick equation).
In chronic exercise (someone who does it for a few weeks), conditioning decreases heart rate and blood pressure and increases cardiac stroke volume to supply oxygen more efficiently, largely by reducing the myocardial oxygen demand.
In short, heart rate is just one of several factors in the number of burned calories. Unfit people have a high heart rate with minimal exertion, which does not mean they burn many calories.
What determines your stride? I’d like to develop a longer stride for normal running speeds. I figure it will be less physically jarring due to less strides per mile. However, those strides will probably be more intensely jarring per stride; so that may cancel out any benifits.
Can doing leg lifts for high repititions to work out the quads help to increase stride length? My hamstrings aren’t very flexible either, which is probably the biggest factor.
Interesting; though, after a quick trawl, I’ve not been able to find any support for your linear contention. For example, Arsac & Locatelli (2000) use a square relationship in an equation expressing the energy required to overcome air resistance (BTW, I’m not sure that everyone will be able to follow the link to the article text).
There’s a similar result in Davies (1980); again, the force required to overcome air resistance is proportional to air velocity squared. In fact, the work per unit time varied pretty much as the cube of airspeed.
Anyway - I’d be interested in any cites for your linear contention. Must say that it runs contrary to anything I’ve heard in passing, and doesn’t seem evident in the literature, after a quick search.
