Manipulation effects of prior exercise intensity feedback by the Borg scale during open-loop cycling

To verify the effects of exercise intensity deception by the Borg scale on the ratings of perceived exertion (RPE), heart rate (HR) and performance responses during a constant power output open-loop exercise.

Eight healthy men underwent a maximal incremental test on a cycle ergometer to identify the peak power output (PPO) and heart rate deflection point (HRDP). Subsequently, they performed a constant power output trial to exhaustion set at the HRDP intensity, in deception (DEC) and informed (INF) conditions: DEC--subjects were told that they would be cycling at an intensity corresponding to two categories below the RPE quantified at the HRDP; INF--subjects were told that they would cycle at the exact intensity corresponding to the RPE quantified at the HRDP.

The PPO and power output at the HRDP obtained in maximal incremental tests were 247.5 ± 32.1 W and 208.1 ± 27.1 W, respectively. No significant difference in the time to exhaustion was found between DEC (525 ± 244 s) or INF (499 ± 224 s) trials. The slope and the first and second measurements of the RPE and HR parameters showed no significant difference between trials.

Psychophysiological variables such as RPE and HR as well as performance were not affected when exercise intensity was deceptively manipulated via RPE scores. This may suggest that unaltered RPE during exercise is a regulator of performance in this open-loop exercise.