How reducing your training before a big race can boost your performance

Tapering explained

Tapering, or taking things easy before a big race, can boost your performance on race day

A taper is a period of rest or reduced training immediately preceding a race. Done right, it can boost your performance. The problem, according to Joe Friel, author of The Cyclist’s Training Bible, is that “if you do the taper right, your fitness will decrease slightly”. That’s a concept endurance athletes have real trouble getting their heads around.


How tapering works

Tapering is based on the assumption that training increases fitness levels and fatigue levels simultaneously. As you train harder you get fitter — which increases your performance — but you also get more tired — which decreases your performance.

Decreasing volume and maintaining intensity resulted in significant performance improvements, but maintaining volume and decreasing intensity resulted in a performance drop

Tapering works because when you decrease training your fatigue level falls faster than your fitness level.

So, even though fitness will decrease slightly during a taper, the greater lack of fatigue means performance will be better.

Countless studies have proven this. Researchers at Ball State University in Indiana found tapering brought an improvement of four percent, while a combined study at several Canadian universities found that cutting training volume by 50 percent for one week improved the 20km time trial performance of trained cyclists by 1min 9sec on average. Gathering all the studies together, it seems an improvement of between one and six percent is possible if you do it right.

Which method of taper training?

But doing it right isn’t easy, nor is it an exact science. Though tapering involves reducing your training load, you can do this in a number of ways. You could:

  • Cut the number of kilometres you ride per day (reduce training volume)
  • Cut the speed at which you ride them (reduce training intensity)
  • Keep your daily rides exactly the same but train on fewer days (reduce training frequency)

Many studies have looked at these different methods and combinations to see which works best.

The best known was by a team at the University of Illinois, who showed that decreasing volume and maintaining intensity resulted in significant performance improvements, but maintaining volume and decreasing intensity resulted in a performance drop. Further research has refined the cut volume/maintain intensity strategy.

Researchers from the University of Lille in France collated all known taper studies and drew some overall conclusions:

1. First, they found that best results were achieved following a reduction in training volume of 40 to 60 percent, depending on the individual and the ferocity of previous training. Friel, for example, says: “With my athletes, I vary the length and severity of the taper depending on the stress the athlete has been experiencing and how long they’ve experienced it. The longer the athlete has been at a high training stress, the longer the taper will be.”

2. The second conclusion was that training frequency should be maintained or reduced by a maximum of 20 percent. So for the most part, you still need to ride as often as you normally would, just for half the distance.

3. The final — and arguably most important — conclusion is that intensity must be largely maintained to ensure fitness levels don’t drop off drastically. This is an important point, but one that cyclists often take too far by actually increasing intensity rather than simply maintaining it.

Buoyed by the energising effects of the taper, many cyclists throw in shorter, faster reps with the intention of ‘sharpening up’. But research from Ball State University found this approach may be counterproductive.

“Our research shows tapering primarily benefits the type II or fast-twitch muscle fibres,” said lead researcher Scott Trappe. “These fibres are broken down during very high intensity training, so too much intensity during the taper can have a negative impact on muscle changes, which will hurt your performance.”

How to determine the ideal length for a taper

Another crucial aspect of the taper is timing. How long should you allow? The studies show that, on average, two weeks seems to be about the optimum length for a taper, but it depends on the length of the training block preceding it. If you’ve been training hard for six months prior to the race then a three-week taper is likely to be more effective.

Dr Phil Skiba of the University of Wisconsin has devised another strategy. Using data from hundreds of athletes, he has worked out a formula for calculating two days crucial to tapering.

  1. The first is the day on which training will have a maximum positive effect on your race. Training adaptations take a little while to fully work through so this day is often a week or two before the race at least.
  2. The second is the day on which training starts to have a negative impact on your race performance because it’s so close to race day that the fatigue outweighs the fitness gains.

“While two weeks is a good starting point, with a little trial and error — or by using my software at — you can calculate these two days,” said Skiba. “You want to reduce your training volume between them, aggressively at first and then more gradually.”

Crash training is generally only a tactic for very serious cyclists, but it can be pretty effective and maybe should be used by more people

This latter point is another area where cyclists often go awry. Studies show a progressive taper is superior to one that rigidly reduces training volume on a week-by-week basis. But this does not mean — as many think — that you reduce training volume slowly at first and then dramatically in the final days. In fact, the reverse is true. The best results are obtained by cutting volume in half at the beginning of the taper and then largely maintaining that until race day.

Tapers, then, are not as easy as they appear. But that isn’t an excuse for not believing in them.

“In my experience, while most people are very willing to put in the necessary training, they are often afraid of tapering because it feels like they’re losing fitness and they’re worried their performance will drop,” said Trappe. “The data simply doesn’t support this. You have to trust it.”

Pre-taper ‘crash’ training

There is also evidence that a period of extremely intense training immediately preceding the taper can be beneficial.

A study at the University of Saint-Etienne in France found that 28 days of ‘overload’ training prior to the taper significantly increased final performance in trained cyclists. However, it also meant that for best results the taper had to be more dramatic and longer.

“Crash training is generally only a tactic for very serious cyclists, but it can be pretty effective and maybe should be used by more people,” said Skiba. “Given that cycling is a low-impact sport, the chances of hurting yourself are low — though I’d recommend trying it for just a few days at first, in the week immediately before the taper.”

A word on the controversial carb load

Nutrition is another crucial aspect. Some experts recommend maintaining a normal diet until the final week when an optional period of depletion (now out of favour with many) is followed by a carb feast to fully top up glycogen levels. However, many cyclists report that carb-loading makes them feel bloated and slow — hardly ideal preparation.

Researchers from the University of Western Australia have an ingenious solution.


They found glycogen storage is most effective immediately after high-intensity exercise, but that the bout of exercise need only be three minutes long. So they recommend that two or three days before a race, athletes should do three minutes of flat-out exercise and then consume a high amount of carbohydrates over the next 24 hours — the first 20 minutes being the most important. After this, normal diet can be resumed, so athletes don’t feel bloated, but tests show they’ll have super-high levels of glycogen for race day.