“Concrete vs. Asphalt” - Which is the Better Running Surface?
Posted July 28th, 2006 at 5:30 AM by Jim Fortner
Section: Running & Training, Injury & Rehab, Training Tips, Health & Fitness, Injury & Rehab, Exercise
A note from the TFS: We are pleased to welcome Jim Fortner as a guest contributor to The Final Sprint. Jim is an extremely knowledgeable runner and talented writer. Make sure to also check out “Jim2’s Running Page”, his own personal running and advice site.
Below you will find his latest post concerning the debate over running surfaces - what’s better: concrete or asphalt?.
Concrete is a much harder surface than asphalt or macadam. It’s the worst commonly encountered surface that you can run on and should be avoided like the plague. To compare the “hardness” of concrete and asphalt, hit each surface with a hammer and see how it feels to your hand and arm. You will find quite a difference. You will leave a dent in the asphalt, but not in the concrete.
When running, your feet strike the surface with a force of up to 6 times your body weight. And unless you land dead midfoot all that force is concentrated on a very small landing surface. For a typical heel striker, it’s maybe a square inch or two. Let’s assume that a person who weighs 120 pounds lands at 5 times body weight with a heel strike that covers two square inches. That’s equivalent to an initial strike force of 300 pounds/sq in (equivalent to 3600 pounds/sq ft) upon contact. If asphalt is really 10 times “softer” than concrete, as the study that Bill mentioned said, that would make a big difference in initial energy dissipation vs that which shoes, normal pronation and body structure have to absorb. (BTW, that’s also the problem with a non-overpronator using stability or motion control shoes. They unnecessarily restrict normal pronation, which is a natural shock absorption biomechanic, and result in an increase in the force that the body’s skeleton and joints have to dissipate.)
I can tell a very distinct difference in how running on concrete feels compared to asphalt. There are a couple of wide concrete sidewalks that I cross during an 8 mile run on the B&A Trail. I really know it when I cross over them. I would not want to run a marathon that is mostly on concrete. I don’t even like to run 10k’s on concrete.
Actually, there are a few other surfaces that are even harder than concrete, such as brick, stone and steel. Fortunately, they are seldom encountered when running. I’ve always thought the people who run regularly on the brick waterfront promenade in Baltimore’s Inner Harbour were being foolish. And steel is a surface that is usually encountered only when running on the deck of a ship…..like a few hardcore marathoners did in the 2001 Antarctica Marathon when weather conditions prohibited running on the snow and ice.
The state of Georgia announced plans to build a concrete walking/running trail a year or so ago in the Atlanta area. A Mervite who is a very good runner (Emorydoc) led an effort to try to get them to construct it of asphalt or macadam instead of concrete, but a construction company that does a lot of business with the state “donated” the concrete. So the state chose to go the cheap route instead of considering what was best for the intended purpose.
If most of your running is on concrete, I would put that at or near the top of the list of suspects for recurring injuries. You would be much better off running on grass or dirt alongside the concrete, if you have that option.
NOTE: This article merely makes the case that asphalt is easier on your joints than concrete (When given the choice between a concrete and asphalt path or trail). HOWEVER, everyone is advised to be extremely careful when running on ANY surface. It is NOT advised that you run on streets and other thoroughfares because of the obvious danger caused by passing cars, traffic, etc. Always err on the side of caution.
Picture from: [Asphalt Pavement Association of Indiana]
Related Stories:
- June 3 Will Be National Running Day in USA
- TFS Running Podcast: Jordan Hasay on How To Deal with Success at a Young Age
- Beat the Running Blahs
Tags: asphalt, biomechanic, body structure, concrete, energy dissipation, initial energy, injury prevention, overpronator, pronation, roads, running surface, sidewalks
Like what you see? Subscribe to our feed!
The Final Sprint
There are so many things to disagree with in this article…
Frankly, if you wear shoes, it doesn’t matter a tinkers cuss whether you’re running on asphalt or concrete. The hammer analog is silly. Unless you’re running in steel bottomed shoes, you’re not going to impact the ground or jar your body self that way. Again, shoes are the great equalizers of terrain.
If you are in a car driving on the right side, you’ll notice that all municipal roads are built with a gradual right slope off to the right. This is done for two reasons: Should a driver become incapacitated, it encourages the vehicle to fall off the road to the right instead of left into oncoming traffic. The second is to promote water runoff.
I mention this because, if you run on asphalt, there is a good chance that you are running at a perpetual slant which stands more chance of doing joint, hip and back damage than any difference between concrete and asphalt might.
Slightly off topic: For those who run against traffic in bike lanes, running against traffic in a narrow swath of asphalt clearly labeled ‘bike lane’ makes about as much sense as running into oncoming traffic. You risk getting hit by someone who could be doing between 20 and 50 mph.
The only argument I see in favor of road running as opposed to sidewalk running is that you are less likely to be surprised by changes in terrain (like the sudden appearance of wheelchair accessible ramps or curbs)
Finally, you can’t really generalize running on brick because there is no consistent standard for mounting brick. If you mean a modern cobblestone road that is built to withstand automobile traffic, the underpinning is much like a sidewalk. If you’re talking about a garden path where the brick is set in earth, its a different story. Still, I maintain that if you’re wearing shoes, it simply doesn’t matter. Any difference you feel between these surfaces is psychological.
April 1st, 2007 at 2:26 pmThanks for your comments. It is obvious that we disagree, which is OK. There are many running-related topics on which not all runners will agree. And we all learn by sharing different opinions and perspectives.
Yes, running shoes are designed with shock absorbtion features. But they don’t absorb it all. If they did, there would be no running injuries resulting from “pounding”, such as many stress fractures.
Also, not all running shoes have the same shock absorbtion capabilities. Racing flats have almost no cushioning. Light weight trainers just a little more. Motion control shoes are firmer than cushioned shoes. The degree of injury protection that one gets from shoes is dependent on the type of shoe one runs in.
The combination of one’s body and the surface on which one runs has to deal with the portion of shock not absorbed by shoes. Concrete can be as much as 10 times harder than asphalt. On a “risk of injury” scale, where 1 is the greatest risk of injury and 10 is the least risk of injury, concrete is rated 2.5 and asphalt is rated 6….that’s a significant difference.
I certainly agree with you about the considerations of road camber and “playing in traffic” in choosing whether to run on a concrete sidewalk vs. an asphalt road. However, not all roads have a significant camber or heavy traffic. And paved trails that are so popular today, such as the one where I do most of my running, have none at all. Besides, the subject of my essay wasn’t total running environment, but specifically surface differences.
April 1st, 2007 at 6:19 pmI agree with the person who calls himself/herself “Mythbuster,” that running on a slanted surface is not good. On the rest, Jim Fortner is clearly the better informed. There is another factor that makes asphalt a much better running surface — the coefficient of friction. Dry concrete brings the foot to a stop much faster. That little bit of slip on asphalt really helps. I have been a runner, a part-time coach, and a lifelong engineer. I have seen the difference in many people over many years.
April 21st, 2007 at 12:05 amWe have a controversy with some runners/ walkers saying that asphalt is softer than concrete. Its more shock absorbing, but I do not think your feet can really benefit as much as choosing the best pair of shoes!
May 8th, 2007 at 9:59 amWhere is research or studies? Consider the dangers of runners in the street. Some even go side by side!!! Cars, golf carts, bicycles, and a setting or rising sun is too much competition.
Don’t be lazy and unsafe! Find a track at a local school and run safely, or find a safe walk.
As alluded to in the article, a “dent” or compression of the asphalt is what would offer any type of “cushion” for a runner and give it an advantage over concrete.
The hammer test mentioned in the article is misleading in that if you are hitting the asphalt hard enough to dent it, you are striking the surface with far greater force per square inch than any runner could possibly achieve.
Taking an average paving asphalt compression strength of 8.5 MPa (1233 psi), the same 120 pound runner would have to generate more than four times the 300 psi heel strike force quoted in the article to make a dent. That’s 20 times that person’s body weight and impossible to achieve when running.
I would argue, therefore, that there is no relevant advantage to running on asphalt instead of concrete.
June 20th, 2007 at 3:27 pmSince this issue was covered very well by WillRunForBeer in the link above, I’ll just quote him:
“a rough guesstimate could be:
Shoe heel compression: 3 mm
Heel tissue compression: .2 mm
and then
Asphalt compression: 0.05 mm (basically hard as hell)
Concrete compression: 0.02 mm
So running on asphalt would yield a 3.25 mm compression versus on concrete would yield 3.22 mm compression. Hardly a difference when your shoes could vary by even more just by being cold versus warm!”
To me, the main issue is that the hardness of the surface is in series (to use an electrical engineering term) with the softness of your shoes.
September 26th, 2007 at 4:33 pmhere’s the link…
http://www.coolrunning.com/forums/Forum13/HTML/009041.shtml
September 26th, 2007 at 4:34 pmConsider the surface textures of asphalt and of concrete. Concrete sidewalks have very smooth and flat surfaces. Asphalt normally has a rougher, or more porous surface. I believe that as a runner’s shoe strikes an asphalt surface it actually absorbs the sole of the shoe whereas a concrete surface will not. The textured surface of asphalt therefor will soften the impact.
October 24th, 2007 at 11:55 pmConcrete is also poured and formed at an angle to promote water runoff. It doesn’t appear so to the eye because sidewalks are so narrow.
December 29th, 2007 at 4:00 pmConcrete vs. a track????
No comparison!!!
I am a Coach and see on a daily basis how young athletes should not be subjected to concrete….Especially if a track is available.
….wanted to throw this in just in case a student athlete read this thread.
Keep running,
May 21st, 2008 at 11:57 amCoach Pete
I have often wondered about the asphalt vs. concrete dilemma. I have run on an asphalt trail now for two years and actually prefer it to the softer material at Memorial Park in Houston, the number 1 runner’s park. I agree that shoes make the most difference but I feel that just running the concrete streets are going to lead to injuries quicker that other surfaces. Thanks for the input and opinions by all.
July 23rd, 2008 at 11:06 amConcrete’s a bear, but when you’re training for a marathon that’s primarily run on concrete, whaddya do? You have to train on the surface to be able to withstand it over the long haul.
July 23rd, 2008 at 11:53 am[…] If you must forgo sand and field, run on asphalt. Not sidewalk concrete, but asphalt: they say it has more give. If you waive country roads flanked by miles of corn crops and ranch homes, commit to city bike lanes, subdivisions well-stocked with Priuses (or is that Prii?), and side streets with 50s-style, single-family dwellings safeguarded by stop signs on every corner. […]
September 25th, 2008 at 2:02 pmI’m afraid I have to agree and disagree with both. Running shoes do lessen impact, but if you are running on a surface such as concrete, the soles and supports of the shoes quickly wear down. I had a coach in high school who made us run on sidewalks for ten mile workouts, and there was not one person on the entire team who did not have an injury. Indeed, at one point only half of our runners were fit to race. If possible, run on forest trails or something similar, something not a paved surface at all. If you don’t have such a surface available, run along the very edge of the road facing traffic. Yes, there is a slope to any road, but how many cross country courses that you find are perfectly level? None.
October 3rd, 2008 at 10:05 amAsphalt vs Concrete as a running surface. The assumption of a runner being able to tell the difference between the two surfaces for comfort and reduction to injury is far from conclusive in the above articles. We are lacking a defined analysis of the strike force of a person and shoe on both surfaces to make any type of informed opinion. Until there is a study undertaken to conclude a human having the ability to compress bituminous because of the strike force under a cushioned shoe, I will remain unconvinced that concrete is any more impactive to run on than bituminous or other hard surfaces. John
December 16th, 2008 at 3:43 pm