Thermodynamics in Track and Field and Other Geeky Stuff

I like to explore the depths of track and field websites. Geeky, huh? The IAAF website, for instance, has some 62,200 pages (62,400 pages, just 4 hours later) over which I can obsess. While exploring the web pages of our sport's international governing body, I ran across a section titled New Studies in Athletics that I had previously overlooked for some reason.

While exploring it I found some easily-digestible summaries of some fascinating track and field research studies. These summaries are so short that even the complex scientific information they contain can be absorbed within a minute or two. Here's one that is so short, I'll just quote it in its entirety:

The effects of warm-up and pre-cooling on endurance performance in high ambient temperatures
Wednesday 18 April 2007
By Sandra Ückert and Winfried Joch

It is well established that warm conditions have a detrimental effect on endurance performance. If skin temperature is exceeded by the ambient temperature, heat dissipation is impaired and heat storage is likely to occur. A warm-up, which by definition entails increasing body temperature, is generally considered a vital part of the preparation for competition - including endurance performances in hot weather. On this understanding, the question arises if cooling prior to competition (pre-cooling) might be a better alternative. Twenty subjects performed two laboratory endurance tests in conditions of high ambient temperature and relative humidity. One test followed a 20-minute warm-up and the other a 20-minute pre-cooling procedure. The comparison of results shows that pre-cooling significantly extends the time to exhaustion and slows the increase in both body core temperature and heart rate. The authors conclude that pre-cooling, as opposed to a warm-up, optimises thermoregulatory processes before physical effort in warm conditions.

I'd never imagined that a warm-up, as opposed to a hot-weather "pre-cooling" procedure, could be so detrimental to a distance runner's performance during a hot-weather race. Back in high school, we always warmed up prior to training runs and races whether it was 95° (usually late during track season) or 45° (usually late during cross-country season). The concept of a hot-weather "pre-cooling" procedure is so simple yet logical, I wonder why I hadn't thought of it myself.

Gender Differences in Athletic Performance

After I heard the radio broadcast of Meseret Defar's fabulous Women's 5000m world-record run yesterday, I recalled a theory stating that due to physiological gender differences (VO₂ max, body fat %, efficiency of stride, etc.) there is approximately a 10% difference between men's and women's world records. I also recall hearing that the longer an event, the less difference there are between the two genders; either that, or the advantages women have (smaller mass means less heat required to be expended, fat is burned more efficiently) in the longer events cancel out the disadvantages they may have (see above). I wondered if that was true for the 5000m based on this new record so I did a little analysis.

Meseret's record of 14:16.63 is indeed only 11.6% slower than the men's world record of 12:37.35. Looking at the 5000m, the statistic seem to bear out the theory. How do women compare in other events?

100, 6.9%
200, 9.5%
400, 9.3%
800, 10.7%
1000, 11.4%
1500, 10.6%
Mile, 11.7%
2000, 12.5%
Steeplechase, 12.5%
3000, 9.3%
5000, 11.6%
10,000, 11.0%
20,000, 13.0%
Hour, 15.1%
25,000, 15.1%
30,000, 15.6%
100/110 Hurdles, -5.5%
400 Hurdles, 10.6%
High Jump, 17.2%
Pole Vault, 22.4%
Long Jump, 19.0%
Triple Jump, 18.0%
Shot, 2.2%
Discus, -3.5%
Hammer, 11.5%
Javelin, 37.4%

The statistics highlighted in red are for those events in which there is an advantage of some kind in the woman's event (4kg for the women's shot put compared to 7.26kg for the men's shot put, for instance, or shorter distance and shorter implements in the women's 100m hurdles vs. the men's 110m high hurdles). The women's record is actually faster than the men's mark in some of those events (100m/110m hurdles and Discus) and there is virtually no difference in another (shot put). In one event (the javelin throw) the weight of the women's implement is 0.75% of the men's implement, yet there is a significant disparity of 37.4% between the women's and men's records.
In many of the events without a weight/distance advantage there is indeed a close to 10% difference, especially in the track events.

The statistics for the field events are a big surprise. The disparities are much larger than I thought they would be. At the other end of the spectrum, the % difference of only 6.9% in the 100m was a big surprise to me, too. Was Flo-jo pumped up? There was some controversy about the validity of her performances, even after her death.

The statistics for the longer events are also a surprise. The statistics don't seem to bear out a woman's endurance advantage. Perhaps we need to go beyond the marathon to begin to see the gap closed between men's and women's performances? I also wonder if less experience for women on the international stage accounts for the larger gaps in performance, especially in the pole vault and the triple jump.

Are any these statistics a surprise to you, too? Either way, please comment on this post and let us know!

Jet Lag in Oregon?

Last week, during a post-race interview seconds after winning the 110m Hurdles at the Reebok Grand Prix in NYC, Chinese superstar Xiang Liu admitted to having jet lag. His winning time of 12.92 was only four one-hundredths off his world record of 12.88. Obviously, the jet lag didn't affect him too much, or else he found a way to handle it.

Jet lag is a real physiological symptom that affects 90% of us. Most world-class athletes are used to dealing with its effects. Some of the international athletes competing at this weekend's Prefontaine Classic will have to cross at least 10 time zones in order to get there. They'll be dealing with it for sure. Let's hope that are as successful at doing so as Xiang Liu was last week. Speaking of Xiang Liu, how fast will he run now that he's had a week to recover from his jet lag?