Author(s): STAVROU, N.2, KREKOUKIA, M.1, PSYCHOUNTAKI, M.2, SPILIOPOULOU, P.1, ZARAS, N.3,4, BOGDANIS, G.1, TERZIS, G.1, Institution: NATIONAL & KAPODISTRIAN UNIVERSITY OF ATHENS, Country: GREECE, Abstract-ID: 1362

INTRODUCTION:
Motor imagery represents one of the most widely used cognitive-behavioral interventions to enhance sports performance [1]. Training volume in a resistance program consists major variable for the development of muscular strength and especially muscle hypertrophy [2]. However, the long-term effect of motor imagery on both muscular performance and muscle mass remains unclear as it is unknown if the application of this specific cognitive-behavioral technique can influence the daily training volume an exerciser can perform. Aim of the study was to investigate the long-term effect of motor imagery, combined or not to resistance training, on muscular performance and morphology.
METHODS:
Fifty-eight healthy moderately resistance-trained participants (29 men and 29 women) with no mental preparation experience were randomly assigned to one of four experimental groups: a resistance-training group (RT) (n=15), a resistance training and motor imagery group (RT+MI) (n=15), a motor imagery group (MI) (n=20), or a control group (CTRL) (n=8). Resistance training consisted of two weekly sessions performed on nonconsecutive days for 8 weeks. Resistance training sessions (altogether 16) included of four sets X six repetitions (85% of 1RM) in leg press and Smith machine semi-squat exercises. Motor imagery protocol consisted of two supervised sessions/week (~20min/session) and 5 times/week self-guided sessions (~10min/session). Body composition (Dual Energy X-ray Absorptiometry, DEXA), maximal leg isometric force (MLIF), maximum strength (1-RM), counter movement jump height (CMJh), and quadriceps cross sectional area (CSA) using B-mode ultrasonography were evaluated.
RESULTS:
Lower extremity lean body mass, total quadriceps, and vastus lateralis C.S.A. were significantly and similarly increased in RT+MI and RT groups. MLIF, 1-RM and CMJh were also increased significantly with no differences between RT+MI and RT groups. Significantly and similarly was increased leg press and squats training volume (sets X repetitions X load) per week in RT+MI and RT groups.
CONCLUSION:
In conclusion, adding motor imagery to a resistance training program leads to increases in maximal strength, power, and muscle mass. The combination of resistance training with motor imagery doesn’t seem to outperform the effect of physical practice on muscular performance and hypertrophy.

1. Guillot, A., and Collet, C. (2008)
2. Mcleod et al. (2023)