Heavy Stuff

The case for weight classes in road racing

Ever wonder about the “Clydesdale” and “Athena” division checkboxes on your race registration? Why is it that some road races and triathlons allow big-bodied participants to compete in their own categories? Well, you’re not alone. The idea, which allows big-framed runners—generally 200-plus pounds for men and 150-plus for women—to compare their performances against athletes with a similar build, has been divisive since it was first introduced to running in the 1980s.

Critics have always tended toward the same arguments: 1) A race is a race is a race: don’t water down the competition by creating handicaps in addition to sex and age group categories; 2) It’s just incentive for out-of-shape schlubs to stay that way, rather than be their best selves by dropping the pounds; and, perhaps most cutting, 3) It only prolongs the already interminable awards ceremony.

Clydesdales, on the other hand, argue that it’s only fair: a 150-pound runner, say, has a distinct advantage over someone who weighs 200 or more pounds. Not only does that seem intuitively true (witness the featherweights gracing the open division podiums), but science and statistics bear it out. In the late 1980s, Baltimore-area statistician Joe Law, founder of the Clydesdale Runners Association, analyzed the weight of 20,000 runners who raced at distances of 10K or more. He found that weight and speed became inversely proportional once men reach 170 pounds. Slighter runners in the same age group almost always performed better. Law suggested that, for example, a 210-pound man who runs a 51-minute 10K (8:14/mile pace) is performing as well as his 150-pound peer who does it in 38 minutes (6:08/mile).

The simple physiological explanation that Law’s statistics revealed is that the body supplies oxygen and energy to working muscles, so lightening the load makes that process more efficient—VO2 max increases, in other words. Subsequent studies have revealed that healthy runners race approximately two seconds per mile faster for every pound they lose. You get more miles per gallon from your oxygen. There are even formulas that predict how much time a runner can shave off in a race by dropping weight.

Law was on to something. He coined the term “Clydesdale” after the powerful, hard-working and relatively slow draft horse breed (the women’s “Athena” division is named after the Greek goddess), and his research persuaded some races—including the über-popular Marine Corps Marathon—to create awards based on weight divisions. The practice spread both because it made sense, and because race directors realized that more awards made their races more accessible and garnered more entries.

To find races with your weight division, check out the USA Clydesdale and Filly Racing Federation’s race calendar. And be prepared for a longer-than-usual awards ceremony (we suggest another post-race beer).