Featured Research

from universities, journals, and other organizations

Speed And Endurance Are Doled Out By The Pound

Date:
July 14, 2005
Source:
Rice University
Summary:
The conspicuous size differences between beefy sprinters and lithesome distance runners are dictated by simple rules of form and function, according to new research from Rice University and the Texas Medical Center's National Center for Human Performance. The findings explain why sprinters need greater bulk: They need to hit the track harder to attain their faster speeds. The research appears in the July 15 issue of the Journal of Experimental Biology.

The conspicuous size differences between beefy sprinters and lithesome distance runners are dictated by simple rules of form and function, according to researchers from Rice University and the Texas Medical Center's National Center for Human Performance. Specifically, the greater bulk of speed demons is explained by their need to hit the running surface harder to attain their faster speeds.

Details of the findings linking the speed a runner needs to achieve and the ideal body mass for performance appear in the July 15 issue of the Journal of Experimental Biology in a study authored by Peter Weyand and Adam Davis.

“We found that regardless of the runner's race specialization or gender, we could link an ideal body mass for running performance to how hard a runner needed to hit the ground,” said Peter Weyand, assistant professor in kinesiology and lead author of the study. “The mechanical requirements of running and racing at different speeds are related to the notable differences in body types long-observed among specialized track athletes — and even among animal runners in nature.”

Previously, scientists and others considered massiveness in any form to be disadvantageous for running performance. This idea was based on studies of distance runners and studies of the limited running abilities of elephants and big dinosaurs. However, Weyand and Davis found the trade-offs involved in specialization for speed versus endurance conform to precise body-mass rules.

Their research provides a new twist on an old metric: the body mass index, or BMI, which measures body size based on a person's height and weight. BMI has long been used as a guide on body sizes to be avoided. However, Weyand and Davis unexpectedly discovered that this same index can guide some athletes toward body sizes that will optimize their performance.

In the study, Weyand and Davis, a recent Rice University graduate, found the ideal massiveness for running performance was provided by a constant relationship between the BMI and the force the runners need to apply to the ground at their racing speeds. A practical implication of this finding for runners is that for the amount of ground force required for any race, an ideal BMI exists.

To establish how much ground force was required for different running and racing speeds, Weyand and Davis measured how hard runners hit the surface of a treadmill at different running speeds. Men and women alike hit with forces of about one-and-a-half times their body weight at slower speeds and with as much as two-and-a-half times their body weight at a sprint.

The researchers established an “ideal” body size for each race distance by compiling the average heights and weights of the world's fastest 45 male and female runners in each of the eight competitive racing distances, from 100 meters to 10,000 meters, during the past 14 years.

As they related the force required for the runners' racing speeds to the “ideal” size of the different runners, the researchers found a consistent relationship across all groups. Whether an athlete is male or female, a sprinter, a middle-distance or an endurance runner, the ideal massiveness for running was the same function of how much force the runners needed to apply to the ground at their racing speeds. The specific amount of body mass that they found was needed to regulate ground forces and racing speeds was relatively small: only 2.5 kg of mass per one meter per second of racing speed for males and 1.8 kg per one meter per second for females.

“The results provided powerful support for a basic conclusion,” Weyand said. “Sprinters have more muscle and body bulk because they need to hit the track harder to attain their blazing speeds. In contrast, endurance specialists do not want or need bulky muscles because the ground forces required at their slower speeds are so modest.”

Weyand noted further testing is needed to determine how appropriate BMI guidelines might be for individuals or any given individual athlete.


Story Source:

The above story is based on materials provided by Rice University. Note: Materials may be edited for content and length.


Cite This Page:

Rice University. "Speed And Endurance Are Doled Out By The Pound." ScienceDaily. ScienceDaily, 14 July 2005. <www.sciencedaily.com/releases/2005/07/050712225041.htm>.
Rice University. (2005, July 14). Speed And Endurance Are Doled Out By The Pound. ScienceDaily. Retrieved July 30, 2014 from www.sciencedaily.com/releases/2005/07/050712225041.htm
Rice University. "Speed And Endurance Are Doled Out By The Pound." ScienceDaily. www.sciencedaily.com/releases/2005/07/050712225041.htm (accessed July 30, 2014).

Share This




More Health & Medicine News

Wednesday, July 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Health Insurers' Profits Slide

Health Insurers' Profits Slide

Reuters - Business Video Online (July 30, 2014) Obamacare-related costs were said to be behind the profit plunge at Wellpoint and Humana, but Wellpoint sees the new exchanges boosting its earnings for the full year. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Concern Grows Over Worsening Ebola Crisis

Concern Grows Over Worsening Ebola Crisis

AFP (July 30, 2014) Pan-African airline ASKY has suspended all flights to and from the capitals of Liberia and Sierra Leone amid the worsening Ebola health crisis, which has so far caused 672 deaths in Guinea, Liberia and Sierra Leone. Duration: 00:43 Video provided by AFP
Powered by NewsLook.com
At Least 20 Chikungunya Cases in New Jersey

At Least 20 Chikungunya Cases in New Jersey

AP (July 30, 2014) At least 20 New Jersey residents have tested positive for chikungunya, a mosquito-borne virus that has spread through the Caribbean. (July 30) Video provided by AP
Powered by NewsLook.com
Generics Eat Into Pfizer's Sales

Generics Eat Into Pfizer's Sales

Reuters - Business Video Online (July 29, 2014) Pfizer, the world's largest drug maker, cut full-year revenue forecasts because generics could cut into sales of its anti-arthritis drug, Celebrex. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

    Technology News



      Save/Print:
      Share:

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile: iPhone Android Web
      Follow: Facebook Twitter Google+
      Subscribe: RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins