# Critical Swim Speed

Testing and measurement are the means of collecting information upon which subsequent performance evaluations and decisions are made but in the analysis we need to bear in mind the factors that may influence the results.

### Objective

The objective of the Critical Swim Speed (CSS) test is to monitor the athlete's aerobic capacity (Ginn 1993)[1].

### Required Resources

To undertake this test you will require:

• Swimming pool
• Stopwatch
• Assistant

### How to conduct the test

This test requires the athlete to swim 400m and, following a rest, 50m as fast as possible

• The athlete warms up for 10 minutes
• This part of the test requires the athlete to swim 400 metres
• The athlete gets into the pool
• The assistant gives the command “GO”, starts the stopwatch and the athlete commences the test
• The assistant stops the stopwatch and records the time when the athlete completes the 400m (T1)
• The athlete has an active 10 minute recovery
• This part of the test requires the athlete to swim 50 metres
• The athlete gets into the pool
• The assistant gives the command “GO” starts the stopwatch and the athlete commences the test
• The assistant stops the stopwatch and records the time when the athlete completes the 50m (T2)

### Assessment

#### Calculation of CSS

• CSS = (D2 - D1) ÷ (T2 - T1)
• Where D1 = 50, D2 = 400, T1 = time for 50 metres in seconds and T2 = time for 400 metres in seconds

Enter the times for each distance and then select the "Calculate" button for an analysis of the results.

 400 metres seconds 50 metres seconds Critical Swim Speed metres/second

### Analysis

Analysis of the test result is by comparing it with the athlete's previous results for this test. It is expected that, with appropriate training between each test, the analysis would indicate an improvement in the athlete's lactate threshold and critical swim speed.

#### Target Group

This test is suitable for swimmers but not for individuals where the test would be contraindicated.

#### Reliability

Test reliability refers to the degree to which a test is consistent and stable in measuring what it is intended to measure. Reliability will depend upon how strict the test is conducted and the individual's level of motivation to perform the test. The following link provides a variety of factors that may influence the results and therefore the test reliability.

#### Validity

Test validility refers to the degree to which a test is consistent and stable in measuring what it is intended to measure. Reliability will depend upon how strict the test is conducted and the individual's level of motivation to perform the test.

The concept of CSS has proven to be a valid and reliable measure of a swimmer's aerobic capacity. The obtained CSS value can be used to determine the training times for the swimmer (Ginn 1993)[2]. For example:

• Session 4 × 400 metres
• Swimmer's CSS is 1.34m/s
• Target time for each 400 metres is 400 ÷ 1.34 = 298.5 seconds

Ginn also found that the CSS for a swimmer was about 80 to 85% of maximum 100 metre swim speed and 90 to 95% of their 400 metre swim speed.

• Minimal equipment required
• Simple to set up and conduct
• More than one athlete can conduct the test at the same time

• Specific facilities required - swimming pool
• Assistant required to administer the test

### Referenced Material

1. GINN, E. (1993) The application of the critical power test to swimming and swim training programmes. National Sports Research Centre
2. GINN, E. (1993) Critical speed and training intensities for swimming. Australian Sports Commission