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 ↑23.7 ↑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) ↑53.97 ↑56.28 ↑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 ↑9.0 (PF); ↑9.0 (PP) ↑24.6 (PF); ↑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) ↑23.27 ↑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 ↑17.13 ↑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 ↑3.0 to 4.2 ↑4.3 ↑2.6 to 4.0 ↑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) ↑9.3 ↑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 ↑10 ↑14 ↑22 ↑30 5 Fontani et al. (2007) 35±8.7; 30; Male; National Internal MI PG (4 wks/5 dys) -Maximal strength (Karate action: makiwara) ↑9.2 ↑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) ↑10.8 ↑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 ↑0.9 ↑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 ↑129.6 ↑111.3 ↑136.3 ↑112.9 ↑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) ↑35 ↑13.5 6 Ranganathan et al. (2002) NR Internal MI External MI (NR) NR ↑10 ↑5.3 3 AL: athlete levels; MI: mental imagery; PG: physical group; PF: peak force; PP: peak power; wks: weeks; dys: days; ↑: increased; MIC: maximal isometric contractions; NSD: no significant difference compared to pre-training; NR: not reported; SRPMP: stimulus and response proposition mental practice.