Repeatability and validity of the combined arm-leg (Cruiser) ergometer

Area of Science:

• Exercise Physiology
• Rehabilitation Technology

Background:

• Assessing physical fitness in lower limb amputees presents challenges due to limitations of standard ergometer tests.
• A combined arm-leg ergometer, known as the Cruiser, may offer a viable alternative.

Purpose of the Study:

• To determine the repeatability and validity of the Cruiser ergometer for physical fitness assessment.
• To compare the Cruiser ergometer's performance against a standard bicycle ergometer.

Main Methods:

• Thirty healthy volunteers underwent three incremental exercise tests: one on a bicycle ergometer and two on the Cruiser ergometer.
• Repeatability was assessed via test-retest on the Cruiser; validity was evaluated by comparing Cruiser and bicycle ergometer results.
• Intraclass correlation coefficients (ICC) and Bland and Altman plots were used for analysis.

Main Results:

• The Cruiser ergometer demonstrated high repeatability for maximal oxygen consumption (VO2max, ICC=0.84) and maximal heart rate (HRmax, ICC=0.71).
• Validity was also strong, with high ICCs for VO2max (0.86) and HRmax (0.73) when compared to the bicycle ergometer.
• Bland and Altman analyses indicated minimal bias and high accuracy for both VO2max and HRmax measurements.

Conclusions:

• The Cruiser ergometer is a repeatable and valid tool for measuring physical fitness in healthy individuals.
• Its clinical utility for assessing lower limb amputees requires further investigation.