Reading research: Laboratory and field tests in the evaluation of anaerobic fitness in elite hurdlers

After my book review of the autobiography or legendary hurdler, Colin Jackson, yesterday, I thought it would be fun to review a study about hurdling.  It took me a while to find one but I was delighted with what I found…

Hurdlers need speed, agility and endurance (photo from the talented William Warby)

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What’s the study?

It’s called Laboratory and field tests in the evaluation of anaerobic fitness in elite hurdlers, by Janusz Iskra, Adam Zajac and Zbigniew Waskiewicz, 2006, Journal of Human Kinetics.

Historically, hurdling coaches have used the Wingate test to assess how their athletes are progressing through the year.  However, this study sets out to show that certain field tests (standing triple jump, 150m & 500m runs, overhead shot throw) actually provide better indicators.

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So what’s the background?

OK, let’s just cover a few basic points here.  If you’re already familiar with elementary statistical analysis, exercise physiology and you have some experience of track and field, you might want to skip over this section.

Anaerobic systems – most coaches agree that the anaerobic energy pathway is the key one for both 110m high hurdles and 400m intermediate hurdles.

Creatine-phosphate - in 110m high hurdles, the anaerobic production of ATP from phosphocreatine is dominant.  In fact, in the 110m hurdles (and other sprint races lasting less than 15s), the input of anaerobic metabolism has been calculated to exceed 90% by researchers cited in this study.  This stacks up with the exercise physiology textbooks, which identify the creatine-phosphate system as lasting 10-12s only.

Glycolysis - in intermediate hurdles, glycolysis provides the most energy, which is accompanied by high concentrations of lactate accumulated in muscles and blood.  However, the contribution of anaerobic processes is limited to around 70% in this event, with the lactate mechanism providing c. 60% of energy.

Wingate test - the most popular laboratory test of anaerobic fitness is the 30s stationary bicycle Wingate test.  The test begins with a five second countdown to the beginning of the test, during which time the athlete pedals as fast as they can. Upon the start of the test the workload is dropped instantly and the athlete continues to pedal quickly for 30 seconds.  The test measures both power and anaerobic capacity.

Correlation – to make sense of this study, you’ll need to have a basic grasp of what correlation coefficients are.  They are not complicated and in this study, like most others that I have read so far, the coefficient used is Pearson’s coefficient.  This is just a measure of the correlation (or linear dependence) between two variables.  It is presented as a value between +1 and −1.  The higher the value, the stronger the correlation.  

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How was the study set up?

The study was performed on 45 Polish hurdlers (both 110m high hurdles and 400m hurdles) throughout the training year.  All of them were members of the Polish national team in both junior and senior categories.

The study set out to show that certain field tests actually provide better indicators of sports performance than the Wingate test.  The field tests selected were:

• 30m sprint
• Standing triple jump
• Backward-overhead shot put throw
• Specific speed endurance runs (110m – 150m, 400m – 500m)

Consequently, these field tests and the Wingate test were repeated at varying points in the year, along with the actual 110m and 400m races.

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What were the results?

The field tests performed well as predictors of sports performance, as follows:

• In the field tests, there were significant differences between hurdlers specialising in the 110m high hurdles and 400m intermediate hurdles.  Thus, the field tests were able to differentiate between the kind of anaerobic fitness required for the 110m hurdles (creatine-phosphate system) and the kind required for the 400m hurdles (glycolysis).
• The field tests showed a positive significant relationship with sport results in hurdling.  In other words, if the athlete improved performance in these field tests, their race time also improved.
• In the 110m high hurdles, the most informative field test was the standing triple jump, which is basically an explosive strength test.
• In the 400m intermediate hurdles, the 500m run was the best predictor of sports performance.
• There were no significant differences between the 110m and 400m hurdlers in the Wingate test.

In summary, the Wingate test is poor tool for the job, while the standing triple jump is great for 110m hurdles and the 500m run is great for 400m hurdles.

This suggests that training power is essential for the 110m hurdlers, while training speed-endurance is critical for the 400m hurdlers.

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Anything else interesting?

One of the great things about actually reading studies instead of just looking at the abstracts is that you get to dig up the sometimes rather bizarre results that researchers often uncover and can’t explain.

In this study, the researchers found that running speed and explosive strength of the trunk and upper limbs remained at similar levels throughout the annual training cycle, while specific speed endurance (150m or 500m run) and explosive strength of the lower limbs (standing triple jump) changed significantly in each training period.

So it looks like it is difficult to maintain specific speed endurance and explosive strength of the lower limbs simultaneously.  The body seems to want to do one or the other but not both at the same time.

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Concluding comments

I have to say that this was one of the most enjoyable studies I have read.  It was clearly set out and very easy to follow.  There was plenty of background, a strong sense of purpose and a clear objective.  If you haven’t started reading research yet but are interested in giving it a go, this would be a great study to start with.