Author(s): SKEIN, M., MURRELL, B., BUZZA, G., Institution: CHARLES STURT UNIVERSITY, Country: AUSTRALIA, Abstract-ID: 1489

INTRODUCTION:
Deception and withholding information have both been shown to impact performance outcomes, regulation of pacing strategies, and neurophysiological responses. Although these approaches are used in a range of training and competition settings, previous research has focused on endurance exercise, leaving the context of resistance exercise unexplored. This study examined the effect of deception and withholding lifting load information on performance and neurological and physiological responses during to-failure resistance exercise.
METHODS:
Ten moderately trained, regular gym attendees completed five sessions containing two sets of bench presses with concealed resistances. Set one was performed at 60% of one repetition maximum (1RM) and deemed the control (18 ± 2 repetitions). During set two, participants completed as many repetitions as they could during one of five randomly assigned conditions: 60% of 1RM with correct information provided (CONT), a misleading 10% increase (DEC-A) or a misleading 10% decrease (DEC-B), or no information provided while lifting 70% of 1RM (WITH-A), or lifting 50% of 1RM (WITH-B). Throughout sets one and two, pre-frontal cortex oxygenation (oxyhemoglobin (O2Hb), deoxyhemoglobin (HHb) normalised tissue haemoglobin index (nTHI)), and triceps, pectoralis major and anterior deltoid muscle activation (EMG) were recorded. Immediately after each set, heart rate (HR), rating of perceived exertion (RPE), and number of successful repetitions were recorded.
RESULTS:
Total repetitions lifted were higher in WITH-B (p=0.001) and less in WITH-A compared to CONT (P=0.001). DEC-A and DEC-B repetitions were lower compared to CONT (p=0.001 - 0.019). Post-set RPE was higher in WITH-A (P=0.007) and lower in WITH-B compared to CONT (P=0.049). Prefrontal cortex HHb levels were significantly higher in set 2 during WITH-A and DEC-A, while lower in WITH-B and DEC-B at various intervals (P= 0.007 – 0.033). Muscle activation in both muscles and HR were not significantly different within or between conditions (P>0.05).
CONCLUSION:
These findings indicate that deception of load during to-failure exercise can impact performance, however, changes in repetitions to failure when withholding information were reflective of changes in load. The changes in RPE appear to be reflective of load despite load information being withheld and may suggest some conscious contribution to workload. Neural activity also indicates greater activity in the pre-frontal cortex when athletes are deceived or are completing work at a higher load. Understanding how athletes respond to information delivery formats may provide useful insights for training and testing practices to maximise performance and manage neurophysiological and perceptual responses.