Effects of Mental Imagery on Muscular Strength in Healthy and Patient Participants: A Systematic Review

Table 2. Effects of mental imagery perspectives on strength performance.

Study	Characteristics (Age; n; Sex; AL)	MI perspective (Weeks/sessions)	Strength task	Results	PEDro scale
Shackell and Standing (2007)	19.8±1.4; 30; Male; Students	Internal MI PG (2 wks/5 dys)	-Hip flexor task	â†‘23.7 â†‘28.3	5
Smith and Collins (2004)	30.44±7.79; 19; Male; Students	Internal MI PG SRPMP (3 wks/2 dys)	-Isometric abduction force (metacarpophalangeal joint of the right fifth digit)	â†‘53.97 â†‘56.28 â†‘55.68	5
Tenenbaum et al. (1995)	24.7±3.6; 45; Male; Students	Internal MI Positive statements (4 wks/1 dy)	-Bilateral knee extension	â†‘9.0 (PF); â†‘9.0 (PP) â†‘24.6 (PF); â†‘9.0 (PP)	6
Smith et al. (2003)	29.33±8.72; 18; Male; Students	Internal MI PG (4 wks/2 dys)	-Isometric abduction force (the right abductor digiti minimi muscle)	â†‘23.27 â†‘53.36	5
Sidaway and Trzaska (2005)	19 to 26 (22.7); 24; Male and female; Students	Internal MI PG (4 wks/3 dys)	-MIC ankle dorsi flexor torque	â†‘17.13 â†‘25.28	6
Reiser et al. (2011)	22.7±2.3; 43; Male and female; Students	Internal MI PG (4 wks/3 dys)	-MIC bench press -Leg press	â†‘3.0 to 4.2 â†‘4.3 â†‘2.6 to 4.0 â†‘8.3	7
de Ruiter et al. (2012)	18–24; 40; Male and female; Recreationally	Internal MI PG (4 wks/3 dys)	-Isometric torque measurement (knee extensors of the right leg)	â†‘9.3 â†‘6.6	7
Yue and Cole (1992)	21-29; 30; NR; Healthy participants	Internal MI PG (4 wks/5 dys)	-Overage isometric contractions of the abductor muscles of the right fifth digit’s metacarpophalangeal joint -MIC of the abductor muscles of the left fifth digit’s metacarpophalangeal joint	â†‘10 â†‘14 â†‘22 â†‘30	5
Fontani et al. (2007)	35±8.7; 30; Male; National	Internal MI PG (4 wks/5 dys)	-Maximal strength (Karate action: makiwara)	â†‘9.2 â†‘8.4	5
Yao et al. (2013)	18–35; 18; NR; Healthy participants	Internal MI External MI (6 wks/5 dys)	-Maximal elbow-flexion contraction (right arm elbow flexion force)	â†‘10.8 â†‘4.8 (NSD)	5
Olsson et al. (2008)	19.3±3.4; 24; Male and female; Elite level	Internal MI PG (6 wks/2 dys)	Jump	â†‘0.9 â†‘1.1	5
Zijdewind et al. (2003)	19-27; 29; Male and female; Healthy participants	Internal MI PG (7 wks/5 dys)	-Plantar-flexors of both legs After 5 weeks After 7 weeks 4 weeks after the training period	â†‘129.6 â†‘111.3 â†‘136.3 â†‘112.9 â†‘125.3	5
Ranganathan et al. (2004)	29.7±4.8; 30; Male and female; Untrained	Internal MI (12 wks/5 dys)	-Fifth finger abductor (distal muscle) -Elbow flexors (proximal muscle)	â†‘35 â†‘13.5	6
Ranganathan et al. (2002)	NR	Internal MI External MI (NR)	NR	â†‘10 â†‘5.3	3

AL: athlete levels; MI: mental imagery; PG: physical group; PF: peak force; PP: peak power; wks: weeks; dys: days; â†‘: increased; MIC: maximal isometric contractions; NSD: no significant difference compared to pre-training; NR: not reported; SRPMP: stimulus and response proposition mental practice.