Mental imagery (MI) or visualization can be considered the go-to mental training (MT) method and is used by the vast majority of sport psychology practitioners. MI is addressed in the context of the Theory of Critical Moments and athlete’s profile (AP) models of peak performance construct bases and the brain-heart-mind-body-motor dynamics they advance in regard to intervention efficiency and efficacy. Athlete is tested for Visualization Responsivity (VR) using the Carlstedt Protocol Visualization Responsivity Test-Athlete Version (CPVR-A). This chapter provides some consecutive autonomic nervous system (ANS)-heart rate variability (HRV) reports that emanate from a professional tennis player who was high in hypnotic susceptibility (HS)/subliminal attention (SA), namely the baseline condition, positive-negative and relaxation visualization scenario-based HRV responses. It presents an MI intervention efficacy case study in the context of actual competition using a repeated A-B-A design. Variance explained in a visualization-based or associated outcome measure should be the intervention efficacy benchmark.

Multi-modal approaches to mental training (MT) involve the incorporation of more than one intervention method in attempts to enhance performance. Intervention amenability and compliance relative to multi-modal MT, as when using singular modalities alone, need to be seriously considered. Multi-modal MT can be very straightforward and designed to specifically address psychological or technical issues or goals independently. This chapter provides an example of a select individualized multi-modal intervention. As with all MT modalities, multi-modal methods must be documented and scrutinized for efficiency and efficacy. Heart rate variability (HRV) and autonomic nervous system (ANS) reports are used to determine intervention efficiency and efficacy. Multi-modal mental training (MMMT), as with any form of intervention that has established efficiency and efficacy, should be carried out independently by athletes who travel to competitions or are assisted by coaches and/or team mates in the absence of a sport psychology practitioner.

Athletes who are high in hypnotic susceptibility (HS) are most amenable to hypnosis/self- and active-alert hypnosis. The feeling that one has when under sport and performance-specific hypnosis is one of mental calmness. Once alert-calmness has been attained using sport-specific inductions, as reflected in changes in autonomic nervous system (ANS) responses from the baseline to hypnosis condition, active-alert hypnosis is used to raise activation or intensity levels and prime motor-technical responses. The American Board of Sport Psychology-Carlstedt Protocol (ABSP-CP) approach to interventions uses heart rate variability (HRV) to test efficiency for all mental training modalities and routinely assesses mental imagery/visualization ability, a correlate of HS/subliminal attention (SA) using HRV. Hypnotic procedures have much potential as a mental training intervention, provided that they are not applied indiscriminately. Athletes who score high in HS or analogue measures, SA, or absorption are usually good candidates for self-and active-alert hypnosis.