Wang, of course, is Wang Junxia, the Chinese female who last year clipped 16 seconds from the 3K world record and shattered Ingrid Kristiansen's 'invulnerable' world 10K mark by an astonishing 42 seconds. Overall, Wang broke three world records at distances ranging from 1500 to 10,000 metres within a six-day span, and her 2:24:07 marathon, though not a world best, was the fastest female effort at that distance in 1993. Qu is fellow countrywoman Qu Yunxia, who complemented Wang's wondrous running by steaming through a world-record 3:50.46 in the 1500 metres. Qu progressed from a ranking of 73rd in the world to the absolute top of the heap in just one short year.

Few people know for certain what's behind these incredible performances but various reports indicate that the quicksilver pair often run about 25 miles per day during certain phases of their training. If so, Wang and Qu have the heaviest training loads in the world, far above the 50-100 weekly miles usually chalked up by elite female runners.

These accounts of high-mileage running have prompted runners, coaches and journalists to ask two key questions: could such prodigious training (150-175 miles per week) really be responsible for the new Chinese records? And second, what sort of improvement can runners realistically expect to obtain from increased training?


The law of diminishing returns
Scientific research concerning the effects of increased mileage on performance is pretty bare-bones stuff, but at first glance the available facts suggest it's unlikely that the 175-mile-per-week schedules are responsible for the Wang-Qu phenomenon. Scientific investigations indicate that expanding one' s training from just five weekly miles to about 25 miles per week can improve performance by around 20-25 per cent, and upgrading weekly mileage from 25 to 50 miles can boost performance by 10 per cent or so. However, changing from 50 to 70 weekly miles nets very small (or no) gains in performance, and going beyond 70 miles per week has not been linked with any measurable physiological benefits but has been related to dramatic increases in the risk of overtraining and injury. The relationship between training mileage and performance gains is an excellent example of the familiar law of diminishing returns.

Obviously, 175-mile-per-week schedules are far beyond the upper bound of 70 weekly miles and shouldn't be expected to produce world records. However, bear in mind that scientific investigations which have explored the effects of high mileage on performance have been carried out with an astonishingly small number of athletes. It is possible that Wang and Qu are 'super-responders', which in exercise physiology parlance means individuals whose adaptations to certain kinds of training are far above the average. In any training programme that hikes the training load of a fairly large number of subjects, you can expect that the majority of people will improve their exercise capacities by around 10-20 per cent. Some unfortunate souls won't improve at all (the 'non-responders') but a few lucky individuals may actually improve by 60-70 per cent. If you're studying a small group of runners, which has always been the case in research projects that have looked at the effects of high-mileage training, the chances of finding any of these 'super-responders' is minimal. However, China, with its population of 1.2 billion, probably contains thousands of exceptional responders. You just have to find them and place them in a training programme which extracts every last drop of fitness.

Although searching for responders in China's densely populated countryside might appear to be like looking for a needle in a haystack, the process is eased by the fact that China contains about 3600 specialised 'sports schools' attended by more than 100,000 athletes between the ages of eight and 14. The most highly-talented individuals graduate to one of 160 technical sports high schools, at which experienced coaches provide guidance.

By contrast, the average eight- to 14-year-old female student in the United States, for example, may, at best, attend two or three 'gym' classes a week. Various scientific studies have shown that actual pulse-rate lifting exercise lasts for a whopping (!) nine minutes per gym class, a far cry from the specialised instruction given the young Chinese.

People who oppose the idea that Wang and Qu have benefited from high-mileage training like to point out that lofty mileages usually haven't worked very well for other elite female runners. However, this disputation is fairly weak. As mentioned, the reality is that Wang and Qu may be 'responders' who react quite differently to high mileage compared to the handful of elite women who have attempted a similar strategy. If runners A, B and C break down after using a particular training method, that doesn't guarantee that competitors D and E will also have troubles when they use the same technique. In fact, they may soar to new heights of perfection. That soaring may not last long, however; the Chinese runners' withdrawal from the London Marathon suggests that their collapse points may have been reached.

When considering the possible impact of high mileage on the Chinese performance, it's important to bear in mind that Wang and Qu don't run 175 miles per week year-round but use a very interesting long-term periodisation schedule ('periodisation' refers to how the frequency, volume and intensity of training change over various periods of time). Since most exercise scientists like to wrap up their research projects in 12-16 weeks, almost nothing is known about how to construct an optimal, long-term periodisation plan. It's possible that the Chinese may have discovered a periodisation programme that simply works better than the schedules used by runners in other countries.

For one thing, the Chinese may be alternating several weeks of high mileage with several weeks of extremely low mileage, a strategy that may intensify both the beneficial impact of high mileage and the positive features of recovery. It's possible, for example, that several weeks at 150 miles per week, followed by several weeks at 30 miles per week, could produce far greater gains in running capacity than a consistent schedule of 90 miles per week, even though the average training mileage would be the same in each case.


Is it mileage or speed?
However, scientific research does suggest strongly that the most productive way for athletes to increase fitness is to train a little faster than usual. For example, experienced runners who replace slow 'junk' mileage with more rapidly paced efforts (at 15K race speed or faster) can improve fairly dramatically within a couple of months without running more weekly miles. The Chinese have this intensity effect covered, too, since coach Ma Junren likes to ride behind his athletes on a motor scooter, honking at them to increase their speed. Still, studies linking faster training with faster racing indicate that a 5 per cent improvement in experienced runners' race times is absolutely huge, and many top-level, maturing runners improve by just 1 per cent per year. By contrast Wang lifted her IOK time from 1992 to 1993 by about 9 per cent.

What about simultaneously boosting mileage and speed? We do know that 'crash' training cycles - 10-14 day periods during which interval training doubles and total mileage soars by 25-50 per cent - can bolster performances pretty significantly. Such methods have produced very remarkable 4 per cent improvements in the race times of experienced cyclists, although the risk of overtraining is high and a two-week recovery period is needed before racing speed actually improves. Also, it's not clear whether a 4 per cent gain after a crash cycle can be followed by another 4 per cent several months later (accounting for 8 of Wang's 9 per cent?) or whether our old friend - diminishing returns - applies here too.

In addition, it' s important to point out that crash cycles aren't very kind to runners compared to cyclists, probably because the high impact forces associated with running produce too much muscle trauma. However, if you have huge numbers of highly fit runners, as in China, you can let most of your runners crash during the crash training and simply pick out the survivors. Ma Junren is reported to be a firm believer in crash training.

For most experienced athletes, upswings in training intensity benefit performances by around 1-5 per cent, well below the progress achieved by Wang and Qu. The advantages of increased mileage depend a lot on previous work loads. Runners who shift from 50 to 70 weekly miles may receive a 1-2 per cent bonus, or they might get nothing at all. At lower mileages the gains are greater. However, all these figures are based on fairly short-term studies in which the new training loads have been kept pretty constant over time. With unique periodisation plans, which might alternate between big upswings in training and subsequent severe downswings, the improvements could be considerably larger.

However, to prevent overtraining, increases in training must always be accompanied by increases in resting AND eating. Each extra 15 minutes of daily training should be balanced by an additional intake of about 250 calories of nutritious food, as well as a yet-unspecified increase in resting and/or sleeping (no one knows the right amount). Otherwise, toughened training may actually impair, not improve, performance.

The Chinese runners reportedly balance their incredible work loads with enormous amounts of massage, significant amounts of snoozing and resting, and hefty intakes of food which would make the average weight-lifter appear to be on a diet. But as to whether their remarkable performances are the result of their high-intensity, high-mileage and uniquely periodised training or are stimulated by other factors, only your Ma knows.

Owen Anderson