Toussaint, H. M., Wakayoshi, K., Hollander, A. P., & Ogita, F. (1998). Simulated front crawl swimming performance related to critical speed and critical power. Medicine and Science in Sports and Exercise, 30, 144-151.

The swimming science literature includes several studies that estimate the contribution of factors to both aerobic and anaerobic energy expenditure in crawl stroke swimming. In this investigation, the authors took various estimates of amounts of influence and formed a statistical model for predicting both aerobic and anaerobic energy output when swimming particular velocities. Many of the values used were assumed, or uncorroborated, and so could include considerable inherent error.

Such models are singular predictors and can only logically predict general/average values for groups. Although individual values can be generated, they inherently involve error due to individual differences across all or some of the variables included in an equation.

The model formed on this occasion included both mechanics and energetics involved in crawl stroke swimming. Actual time dependent aerobic and anaerobic energy release was modeled from swimming flume performances.

The major performance factor considered was that of "critical swimming velocity", the slope of the regression line between swimming distance and time. Theoretically, this is the velocity that can be maintained without encountering exhaustion.

It was concluded that the critical velocity generated in the model was partly indicative of the aerobic energy capacity system. However, the estimation of anaerobic capacity was not supported.

Implication. There is better knowledge and understanding, although incomplete, of the factors that govern aerobic factors in swimming than for anaerobic factors. Prediction of swimming-energy capacities is still a very imprecise science. It also illustrates the fact that sport scientists do not have all the answers for training prescriptions that will beneficially affect performance.

Return to Table of Contents for Hydrodynamics of Swimming.