Houmard, J. A., & Johns, R. A. (1994). Effects of taper on swim performance: practical implications. Sports Medicine, 17, 224-232.
This is a review of the physiological factors associated with tapering in swimming.
1. An incremental, stepwise reduction in training volume (>60%) over a period from 10 to 21 days results in an improvement in performance. This contrasts to a minor reduction (<30%) in training volume which appears to maintain performance.
2. Interval training work (>90% VO2max), with sufficient recovery between bouts to maximize exercise intensity, is desirable. This may be necessary to maintain training-associated adaptations with the reduction in training volume.
3. Weekly training frequency should be reduced by no more than 50 percent, although it is more conservatively suggested as being 20 percent (a substantial reduction results in loss of "feel" for the water and specific movements). It appears that rapid reductions in training frequency reduce performance rather than improve it.
4. The effects of prolonged tapers have not been examined although it does seem that tapers of longer than 21 days would contribute to performance maintenance rather than improvement.
5. Summary: a successful taper involves a substantial (60-90%) graded reduction in training volume and daily high-intensity interval work over a 7 to 21 day period. Training frequency should not be reduced by more than 50 percent although a more conservative reduction would be 20 percent.
1. Improvements in performance during taper occur without changes in VO2max. This suggests that the primary physiological changes are likely to be associated with adaptations at the muscular level rather than with oxygen delivery. VO2max does not reflect the positive effects of taper in swimmers.
2. Taper does not affect submaximal post-exercise measurements (lactate, pH, bicarbonate, base excess) and heart rate.
3. Blood measures have not been conclusively documented as being related to the taper phenomenon.
4. Although not measured in swimmers, muscle glycogen and oxidative mechanisms have both been observed to increase in tapers.
5. Improvement in power is probably the major factor responsible for the improvement in competitive swimming performance through taper.
Taper and Performance
1. A 3 percent improvement in performance is the average change that results in swimmers.
2. The first stage of a taper often produces a "bloated" feeling because of extra water retention in the muscles. For every gram of glycogen, 3 gm of water is stored. This often produces a feeling of being heavy or sluggish.
3. Shaving has been shown to have mechanical and consequent physiological benefits.
4. Positive psychology and realistic expectations (i.e., +3%) are very important.