1. Hodges N J, Franks I M. Modeling coaching practice: The role of instruction and demonstration. Journal of Sport Sciences. 2002; 20, 793-811.
2. Magill R A. Motor learning and control: Concepts and applications. 9th ed. New York: McGraw-Hill; 2011. P. 45-7.
3. Wulf G. Attentional focus and motor learning: A review of 10 years of research (Target article). E-Journal Bewegung und Training (E Journal Movement and Training). 2007; 1: 4-18.
4. Wulf G, McNevin N H, Shea C H. The automaticity of complex motor skill learning as a function of attentional focus. Quarterly Journal of Experimental Psychology. 2001; 54: 1143-54.
5. Lohse K R, Sherwood D E, Healy A F. How changing the focus of attention affects performance, kinematics, and electromyography in dart throwing. Human Movement Science. 2010; 29: 542–55.
6. Wulf G, Prinz W. Directing attention to movement effects enhances learning: A review. Psychonomic Bulletin & Review. 2001; 8: 648-60.
7. Wulf G, Su J. External focus of attention enhances golf shot accuracy in beginners and experts. Research Quarterly for Exercise and Sport. 2007; 78: 384- 9.
8. Shea C H, Wulf G. Enhancing motor learning through external focus instructions and feedback. Human Movement Science. 1999; 18: 553-71.
9. Wulf G. Attentional focus effects in balance acrobats. Research Quarterly for Exercise and Sport. 2008; 79: 319- 25.
10. Ford P, Hodges N J, Williams A M. On- line attentional- focus manipulations in a soccer dribbling task: Implications for the proceduralization of motor skills. Journal of Motor Behavior. 2005; 37: 386-94.
11. Masters R S W. Theoretical aspects of implicit learning in sport. International Journal of Sport Psychology. 2000; 31: 530–41.
12. Porter J M, Ostrowski E J, Nolan R P, Wu, W F W. Standing long jump performance is enhanced when using an external focus of attention. J Strength Cond Res. 2010; 24: 1746–50.
13. Porter J M, Sims Blake A. Altering focus of attention influence elite athletes sprinting performance. International Journal of Coaching Science. 2013; 7(2): 41–51.
14. Sims Blake A. Focus of attention influences elite athletes sprinting performance. Research Papers. 2010; paper 33. http://opensiuc.lib.siu.edu/gs_rp/33.
15. Wulf G, Dufek J S, Lozano L, Pettigrew C. Increased jump height and reduced EMG activity with an external focus. Hum Mov Sci. 2010; 29, 440–48.
16. Magill R A. Motor learning and control: Concepts and applications.10th ed. New York, NY: McGraw-Hill, 2014. P. 93.
17. Porter J M, Nolan R P, Ostrowski E J, Wulf G. Directing attention externally enhances agility performance: A qualitative and quantitative analysis of the efficacy of using verbal instructions to
focus attention. Front Psychol. 2010; 1, 1–7.
18. Porter J M, Wu W F W, Crossly R M, Knopp S W, Campbell O C. Adoping an external focus of attention improves sprinting performance in low-skilled sprinters. Journal of Strength and Conditioning Research. 2015; 29(4): 947-53.
19. Sheppard J M, Young W B. Agility literature review: Classifications, training and testing. J Sports Sci. 2006; 24, 919–32.
20. Beilock S L, Carr T H, Mac Mahon C, Starkes J L. When paying attention becomes counterproductive: Impact of divided versus skill-focused attention on novice and experienced performance of sensorimotor skills. Journal of Experimental Psychology. 2002; 8, 6-16.
21. Castaneda B, Gray R. Effects of focus of attention on baseball batting performance in players of different skill levels. Journal of Sport & Exercise Psychology. 2007; 29: 59- 76.
22. Perkins-Ceccato N, Passmore S R, Lee T D. Effects of focus of attention depend on golfers’ skill. Journal of Sport Sciences. 2003; 21, 593-600.
23. Baker D, Nance S. The relation between running speed and measures of strength and power in professional rugby league players. Journal of Strength Conditioning Research. 1999; 13, 230–35.
24. Berg K, Latin R W. Comparison of physical and performance characteristic of NCAA Division I basketball and football players. Journal of Strength Conditioning Research. 1995; 9, 22–26.
25. Cronin J B, Hansen K T. Strength and power predictors of sports speed. Journal of Strength Conditioning Research. 2005; 19, 349–57.
26. Davis D S, Barnette B J, Kiger J T, Mirasola J J, Young S M. Physical characteristics that predict functional performance in Division-I college football players. Journal of Strength Conditioning Research. 2004; 18, 115–20.
27. Garstecki M A, Latin R W, Cuppett M M. Comparison of selected physical fitness and performance variables between NCAA Division-I and -II football players. Journal of Strength Conditioning Research. 2004; 18, 292–97.
28. Brechuf W F, Mayhew J L, Piper F C. Characteristic of sprint performance in college football players. Journal of Strength and Conditioning Research. 2010; 24(5): 1169–78.
29. Seiler S, Taylor M, Diana R, Lyons J, Newton P, Brown B. Assessing anaerobic power in collegiate football players. J Applied Sport Science Research. 1990; 4, 9–15.
30. McKay B, Wulf G. A distal external focus enhances dart throwing performance. International Journal of Sport and Exercise Psychology. 2012; (1): 1-8.
31. Akbari M, Sohrabi M, Moghaddam A. The comparison effect of the distance of an external focus of attention on dynamic balance task. Journal of Motor Learning and Development. 2011; 2(6): 155-70. (in Persian).
32. Kheirkhiz M, Bahram A. The effect of increasing distance of external attention on electromyography in dart throwing. Journal of Motor Behavior. 2014; 7(19): 51-64. (in Persian).
33. American College of Sports Medicine. ACSM’s guidelines for exercise testing and prescription. 7th ed. Philadelphia, Pa.: Lippincott Williams & Wilkins; 2006. P. 65.
34. Gharakhanlou R. Investigating current position and desighning talent identification indices in football. Tehran: Center of Sport Science and Physical Education; 2002. 1: 1-60. (In Persian).
35. Radfar R. The effect of focus of attention via verbal instructions on performance of basketball throw. Master disseration. Mashhad: Azad Univercity. 2008. (in Persian).
36. Jalilvand M. The effect of skill level and focus of attention via verbal instructions on performance of football pass. Master disseration. Tehran: Shahid Beheshty Univercity; 2008. (In Persian).
37. Porter J M, Anton P M, Wu W F W. Increasing the distance of an externalfocus of attention enhances standing long jump performance. Journal of Strength and Conditioning Research. 2012; 26: 2389–93.