Last weekend’s Gulf Coast Half Marathon really was a ton a fun and I had a great time volunteering! Watching all of my friends finish and being able to cheer them on was pretty special and it was fun to be on the “other side” for once. Many race participants seemed to really love the course and have a blast but there were a few participants who seemed to be upset by the readings on their GPS running watches. I heard a few complaints of runners swearing they ran more than the 13.1 miles and saying how their time would have been better (possibly even set a PR) had they not run the extra little bit of mileage.
I know this course was certified, so the first thing I thought of is…they are not running the tangents…which means they actually DID run more than 13.1 miles. Too bad those 13.1 stickers don’t have a little + sign after them, right? In a race, if you are not running the tangents, you are not racing as efficiently as possible.
The easiest way to explain “running the tangents” is this…running the tangents allows a racer to run the shortest legal distance in a race. This is the fastest and most efficient way to get from the start line to the finish line, and the easiest way to set a PR.
For those of you who have not been to geometry class in a while, a tangent is a straight line that is perpendicular to a curve. When a race course is measured and certified, it is done so from tangent to tangent and by running from point-to-point, you run the measured (and certified) distance. Any variation from running the “tangent route” will add mileage to your race route. Sometimes this variation adds only fractional mileage, but if you are running every curve, you may add up to a quarter of a mile or more to your race! Seriously! Before learning about running tangents, this happened to me and I would get so frustrated.
Here is how running the tangents works…
In races, most runners end up following the solid blue through curves in the race course. However, the dashed line represents the most efficient way to navigate the course. While it may not look like much of a difference, over a full or half marathon race course, this mileage can add up.
Obviously, running the tangent is the smartest and most efficient way to race a course. But, as you can see, it does involve crossing the street from side to side. If you are a middle of the pack racer or you race close to others, be sure to be aware of runners near you when changing directions. You certainly would not want to take out another runner in your attempt to set a PR.
In addition, running tangents means looking ahead. Once you hit a curve in the course, keep your eyes focused in front of you, looking for the next one. This will allow you adjust your running route and stay prepared for what is ahead of you. When heading into a large curve where you are not able to see the next curve or turn, the best rule of thumb to follow is to run as close to the inside edge as possible.
The only time not running to the immediate inside of a curve is when you are running a course with a hair-pin turn. In this situation, making a slightly wider turn by sweeping the turn can be faster. (See image below.) Keep in mind that in this situation, making a wider turn may add a very VERY minute amount of mileage, but in the end, it will help you maintain efficiency. And in a race, efficiency is the KEY.
Overall, by making fewer large curves and running the tangents, you essentially make the race course a straight as possible. By taking the most direct route from start to finish, you are more likely to maintain your pace and momentum. There is no perfect way to run the tangents. The goal is to find out what works best for you in getting through the race course’s fastest route, as quickly as possible.
Have you ever heard of running tangents before? Do YOU run the tangents?
katieRUNSthis 
I’ve never run the tangents before, but you can bet i will be from now on!!
Great post Katie! I’ve definitely been there with the grumbling folks – last half I ran 13.2, and when you hit the wall at mile 12 that extra .1 is killer.
I have heard tangents, just too slow to worry about it. At the end of the GC Half, the GPS watch did say 13.24 miles, Since I didn’t look at my watch during the race, I couldn’t tell where I was off. Plus, I would much rather be over 13.1, than under (like the first Jazz Half marathon course that was measured incorrectly)
Ooh! Science! 😉
This definitely makes sense. You can think about the principle by applying it to a track. If you don’t have to stay in the lane you start in, everyone runs at the center because it’s shorter. If it’s a sprint and you have to stay in your lanes, the starts are staggered to make up for the extra distance the curves add or take away from the middle lane.
Don’t know why I said “center” when I meant “inside” for my track example
I’ve read about tangents, but don’t usually think about it when racing. I do a lot of big races and it’s not easy to do in a crowd! But I agree it can be frustrating … my half PR is currently 2:00:16 … on a course my Garmin measured as 13.2!
I tried to run a straight a line as possible. In a half marathon this summer I actually caught up to a few people on a curved road who were all over the place. And as far as the Garmin goes, I wish people understood that it’s not 100% accurate! Race courses are measured by satellite.
I was going to comment the same thing. Most races are measured by the shortest distance possible (the tangents) on the ground (by like … some kind of special calibrated bike or something). A Garmin watch sends a signal from the watch up to satellites in space. Meaning, the Garmin is not measuring the runner in a straight line on the ground (like the fancy calibrated bike that measured the course is). The Garmin is plotting a line based on a series of points. And those points can be off by a few feet (because they are going to space, and sometimes things like clouds, trees, or tall buildings get in the way). 13.1 miles worth of points, some of which will be off by a few feet = your Garmin will likely record a slightly different distance than what you actually ran. Especially if there are a lot of turns. I’ve heard Garmins get even more confused when you turn.
The best thing you can do is turn OFF the auto lap during races, and manually lap yourself at every mile marker. That way you know your ACTUAL pace, and not Garmin’s close-but-not-100%-accurate pace. This is a good idea if you are trying to PR.
And to see just how inaccurate your Garmin is, log into your Garmin connect dashboard, and zoom in on the maps that Garmin provides for every workout. Even during a run through the suburbs on a clear day, sometimes that little line shows me running through people’s backyards. (For the record, I do not actually do that.)
Geez… typo central up there. I meant race courses AREN’T measured by satellite.
This is really good advice! One strategy that I heard on who-knows-what podcast interviewing who-knows-who suggested running on the edges of the pack for really thick crowds b/c people tend to run in the middle of the road. Running on the edges will make it easier to get past / through the crowd. You might lose a bit of mileage not running the tangents, but you might make up time not dodging other runners. Just a thought!
Think about this…you could use a combination of both strategies. At the beginning of a race, you could run on the edges to break away from the pack and then once you have some breathing room to move a bit more, you could run the tangents! This would be a smart strategy as well.
This was really interesting! I’ve never thought about it. But, I’ll be running the tangents from now on.
When I was running the lakes on Monday I was actually doing this. I wondered if people thought I was weird running from one side of the street to the other.
People who don’t run tangents might think you are being wacky, but if I saw you, I’d think, “He knows how to RACE!”
I did it again yesterday during the Varsity group run. I kept leaving the pack and they must have thought I was soooo weird. But guess what by Mile 3 their watches were beeping almost .1 ahead of mine. Guess it works!
Interesting! I knew this but I found a few of my races are actually short so I wonder if they are measuring the tangents!! These aren’t qualifying courses though so not going to make a big stink about it!
I tried to take a similar approach when I ran my first half marathon last fall. I think it worked!
Of course I’ve heard of it, but definitely just dubbed it a lost cause. I think trying to run them would just distract me. Plus, I think it would be impossible to avoid weaving in the New York City Marathon. So. Many. People.
Interesting! This is my first time hearing about this and it makes total sense. I tried to run the inside line on all the turns at my first half-marathon last weekend to prevent running more than I had to but I didn’t run in a straight line. I also think this strategy would be a good way to keep your mind off the distance you still have left if you are constantly looking ahead to figure out the tangent 🙂
Thanks!
YES! I completely agree with you! I find that running the tangents definitely keeps me distracted during a race and not as focused on the mileage. As long as I’m focused on just getting from point to point, it is easier for me to tune out distractions like nerves, other racers, etc.!
Thanks SO much for this post. I ran my first half a little more then a week ago and was discouraged that I ran 13.3 miles… that extra .2 sucked. A lot. I never knew about running tangents, but it makes SO much sense.
I will certainly be using this information on Saturday.. my next half 🙂
Thanks Katie! Great post and perfect timing going into my half this weekend.
What an informative blog entry! Thank you for sharing this information. This is not something I would have thought of. I have not run my first race yet so this helps me plan my future races (although my first race I think I will just concentrate on running to run and finishing not the technical details). Awesome information!
My cross country coach taught me this when I was entering high school, so I’ve always kept this in my memory bank. It’s funny how many times I’ll be running the tangents and I’ll be far away from all the other runners. Our local 5K is very curvy, and I find myself alone running the tangents while the crowd runs the curves.
I appreciate it every time someone posts on this topic. I get so sick and tired of people complaining a course was measured wrong. If you don’t run the tangents you run further. People also made the good point that Garmins and other GPS devices are not exact. They are close and a great way to measure, but I wish people would stop whining that they ran 13.14.
Thank you for the information! The lightbulb definatley went on!!