Figure 3.

Average compression depth of nine minutes of external chest compression performed by male participants. A: categorised for lower and higher Body Mass Index (BMI); B: categorised for lower and higher heart rate at 75-watt rowing (HR₇₅). Category BMI: 1 = participants with lower BMI; 2 = participants with higher BMI; Category HR₇₅: 1 = participants with lower HR₇₅; 2 = participants with higher HR₇₅; **: p < 0.05. Data are presented as mean ± standard error of mean. For the definition of lower and higher HR₇₅ and BMI, respectively, please refer to the main text.