Table 1.
Summary of the included studies’ characteristics.
| Study | Year | Skill Level | Sample Size | Age (Year) | Task | Verbal Instruction | Outcome | Overall Bias |
|---|---|---|---|---|---|---|---|---|
| Bezodis et al. [50] | 2017 | high-skill | 15 | 22 ± 4 | 10 m sprint | EF: “focus on clawing backwards at the ground with your shoe in every step you take” IF: “focus on pulling your leg backwards just before each contact with the ground” | total sprint time | some concern |
| Ille et al. [18] | 2013 | high-skill | 8 | 20~30 | 10 m sprint | EF: “get off the starting blocks as quickly as possible, head towards the finish line rapidly, and cross it as soon as possible” IF: “push quickly on your legs and keep going as fast as possible while swinging both arms back and forth and raising rapidly your knees” | total sprint time; start reaction time | some concern |
| low-skill | 8 | some concern | ||||||
| Kovacs et al. [19] | 2018 | high-skill | 12 | 20.8 ± 1.7 | 6 m sprint | EF: “focus on pushing the blocks away” IF: “focus on extending your knees” | start reaction time | some concern |
| Porter and Sims [51] | 2013 | high-skill | 9 | 21.11 ± 1.22 | 20-yard sprint | EF: “while you are running the 20-yard dash with maximum effort, focus on gradually raising up. Also, focus on powerfully driving forward while clawing the floor as quickly as possible” IF: “while you are running the 20-yard dash with maximum effort, focus on gradually raising your body level. Also, focus on powerfully driving one leg forward while moving your other leg and foot down and back as quickly as possible” | total sprint time | some concern |
| Porter et al. [52] | 2015 | low-skill | 84 | 20.32 ± 1.73 | 20 m sprint | EF: “while you are running the 20-m dash, focus on driving forward as powerfully as possible while clawing the floor with your shoe as quickly as possible as you accelerate” IF: “while you are running the 20-m dash, focus on driving one leg forward as powerfully as possible while moving your other leg and foot down and back as quickly as possible as you accelerate” | total sprint time | some concern |
| Winkelman et al. [53] | 2017 Exp 1 | low-skill | 17 | 19.41 ± 1.06 | 10 m sprint | EF: “focus on driving the ground back as explosively as you can” IF: “focus on driving your legs back as explosively as you can” | total sprint time | some concern |
| 2017 Exp 2 | high-skill | 13 | 28 ± 4.32 | 10 m sprint | total sprint time | some concern |