Friday, 9 March 2012

#52: I'm Talking About You

Yesterday I posted a news article which included some of the numbers from 'Running USA's Annual Marathon Report.' I just wanted to add my own two cents on what the numbers mean and highlight some of the important stuff. Note: I am NOT a statistician and thus won't attempt to make any bold claims based on these numbers.

So what's going on here:
- Overall participation in the marathon has increased from 143,000 in 1980 to 518,000 in 2011 (a 3.6 fold increase). Since 2000, there has been a 47% increase in the number of U.S. marathon finishers (353,000 vs. 518,000). ie More people are running (completing) marathons than ever before.
- Median marathon finishing times have increased from 4:03:39 in 1980 to 4:42:15 in 2011 for women (+0:38:36), while men's have gone from 3:32:17 to 4:16:34 (+0:44:17). ie People are running slower.
- The median age has increased from 34 to 40 for guys and from 31 to 35 for gals. 36% of male and 24% of female finishers were over 45. ie People are running when they are older.

To me that sounds like a lot more people have been getting a whole lot slower over the past 30 years. But can we really make that claim?

First of all, those finishing times were the median, not the average! Going back to grade school math we see that average/mean is the sum of the values divided by the number of values, while median is simply the middle value (the value separating the higher half of a sample from the lower half). Both measure central tendency but say nothing about the distribution or variance.
Given this series of numbers: 1,2,4,8,16,32,64. The median is 8 while the average is >18!
Applied to running; here are some random marathon times (in hours): 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6. The average here is 4 while the median is 3.5. Thus the median may undervalue the overall trend which is that times are actually even slower than it seems. What this likely means is that there are far more really slow times (say 6+ hours) than there are really fast times (say sub 3)

Now, it's certainly true that the absolute number of sub 3 hours marathons (or sub 2:30 or even sub 2:10!) have increased from 1980 to 2011... but so too have the number of 5+, 6+ and 7+ hour marathons! Which do you suppose is growing faster or makes up the greater percentage of overall results?! I'll bet the farm that it's the latter. Given the overall increase in marathoners, of course it makes sense that some of them will be running faster. Our increasing knowledge of modern sports science including improvements to technology (GPS, apparel, gear), sports nutrition (gels, hydration) and even training practices suggest that the fastest marathon times will likely continue to get faster for some time. Perhaps it won't be long before we see that infamous sub 2 hour marathon. What I'm trying to point out however, is that the percentage of finishers running "fast" is getting smaller and smaller. In 1980, sub 3hr marathons might have made up 10% or more of all finishes; while now that number is likely less than 5%. Hell, it might be less than 1%. I don't have the data to prove this but I'm certain of the trend. The point: A few people are definitely getting faster (running sub 3)... but MOST people are getting slower (running 5+). Those are simply the facts! Interestingly, Boston has the fastest median finishing time of just under 3:45. That shows that their tough admission standards are clearly attracting a high calibre of runner.

Opinions: A likely reason for this is that completing a marathon is now more often the goal than to train and run as fast as one can. Competition is not as important as it was back in the 1980's and running has become more a general physical activity and less a sport . Now, as some people importantly point out, getting people physically active and hopefully healthier is surely a good thing so I'm not saying anything on the value or merits of these trends; simply that they are happening. In terms of making predictions, I would assume that these trends will likely continue for some time, given the increasing appeal and marketing of marathon running for reasons relating to general health, fitness, socialization, and even charity. Running a marathon is a trendy thing to do and people running for these reasons don't put much emphasis on their finishing time. And why would they? The award for running 4.5hrs is the exact same as running 2.5: a medal and a t-shirt!

This is where I could easily turn this post into a massive rant... but I won't! I honestly do believe that increased participation in physical activity is a good thing and if you want to run a marathon, you should! But running a marathon in 3 hours (3.5 for chicks) is NOT the same as doing it in 5hrs and I'm continually frustrated that people ascribe them to be the same or similar accomplishment. One is something ANYONE can do if they invest even a bare minimum of time and effort. The other is incredibly difficult to do and requires a tremendous ammount of commitment, dedication, knowledge, skills and determination. Interestingly, the report shows that: "In 2011, Running USA surveyed more than 11,800 core runners nationwide and reported that those who had completed a marathon in the last two years ran approximately 4.4 days per week for an average of 29.4 miles." That's only 50km per week... to run a 42.2km event! Clearly, the training of the average marathoner has changed drastically from 30 years ago.

The final word: More and more people will continue to run marathons in the coming years. A small minority of people will continue to commit to getting faster and improving but the vast majority of people wishing to simply complete the marathon will do so slower and slower. The big question: In which group will you be?!

Food for thought. The largest marathon in Canada last year was the Scotiabank Toronto Waterfront Marathon. It had 3857 finishers (2479M; 1378F) with an average time of 4:13:05. Of them, 108 men (4.4%) went under 3 hours and 67 women (4.9%) went under 3.5hrs. In contrast, 1385 men (55.9%) went over 4hrs and 727 women (52.7%) went over 4.5hrs. 355 men (14.3%) finished in 5hrs or more while 139 women (10.1%) finshed in 5.5+hrs.

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