Chester Step Test

Abstract

The Chester Step Test (CST) is a submaximal, multi-stage aerobic capacity test. The test requires a low step, heart rate monitor, instructional CD with stepping beat rhythms, rating of perceived exertion (RPE) chart and CST software calculator. The accompanying manual includes graphical datasheets and fitness rating norms geared to age and gender. Providing there are no medical contraindications to moderately vigorous exercise or stair-stepping, the subject is required to step onto and off a low step at a rate set by the beat on the accompanying CD. Every 2 min an instruction is given asking the tester to record the sub-ject's exercise heart rate and RPE-and the stepping rate is then increased slightly. The test continues in this progressive manner until the subject reaches 80% of their maximum heart rate (HRMax) and/or reports a moderately vigorous level of exertion (RPE = 14). Aerobic capacity (or VO 2 Max) is then calculated by entering the exercise heart rates into the bespoke CST software (or by using the appropriate CST graphical datasheet). The test lasts for a maximum of 10 min. On a technical note, CST utilizes the well-established linear relationship between oxygen cost, heart rate and workload together with the American College of Sports Medicine's (ACSM's) metabolic cost of stepping equation , thus enabling aerobic capacity to be predicted from a statistical line of best fit [1-3]. Many workplaces now have recommended aerobic capacity standards for certain groups of workers and CST is a highly suitable assessment tool for 'fitness to work' examinations. Whilst a number of industries test all subjects on a standard step height (e.g. 30 cm for UK fire services [4] and commercial divers [5]), CST can also be administered using different step heights (15, 20, 25 and 30 cm), thereby accommodating a wide range of ages and abilities with no gender bias. Guidelines for selecting step height are given in the CST manual. It is also a useful tool in a variety of clinical and rehabilitation settings to monitor patient aerobic fitness, recovery and exercise tolerance. Relevance to occupational health practitioners CST has been used globally for over two decades in a wide variety of workplace settings including the fire, police, prison, ambulance and military services, oil, gas and offshore wind farm industries and other scenarios where an aerobic capacity assessment is required. For example, the CST is widely used within the UK fire service where an aerobic capacity of 42.3 mlO 2 /kg/min is required for operational duties. Ease of use CST is straightforward to use. It is inexpensive, highly portable, easy to standardize and is a safely controlled submaximal test where heart rates and perceived exer-tion are monitored throughout. It is also highly repeat-able, therefore ideal for test-retest scenarios.