![German international Michael Ballack (R) works hard under the eyes of fitness coach Steve Freitag during the sprint training in Geneva, Switzerland, Tuesday 23 May 2006. The German national team prepares for German international Michael Ballack (R) works hard under the eyes of fitness coach Steve Freitag during the sprint training in Geneva, Switzerland, Tuesday 23 May 2006. The German national team prepares for](https://c8.alamy.com/comp/D3NJJ5/german-international-michael-ballack-r-works-hard-under-the-eyes-of-D3NJJ5.jpg)
German international Michael Ballack (R) works hard under the eyes of fitness coach Steve Freitag during the sprint training in Geneva, Switzerland, Tuesday 23 May 2006. The German national team prepares for
![PDF) The Effects of Repeated-Sprint Training on Field-Based Fitness Measures: A Meta-Analysis of Controlled and Non-Controlled Trials PDF) The Effects of Repeated-Sprint Training on Field-Based Fitness Measures: A Meta-Analysis of Controlled and Non-Controlled Trials](https://i1.rgstatic.net/publication/273780316_The_Effects_of_Repeated-Sprint_Training_on_Field-Based_Fitness_Measures_A_Meta-Analysis_of_Controlled_and_Non-Controlled_Trials/links/5b8ed6f0299bf114b7f5bf4e/largepreview.png)
PDF) The Effects of Repeated-Sprint Training on Field-Based Fitness Measures: A Meta-Analysis of Controlled and Non-Controlled Trials
![Borussia Dortmund's players Mario Goetze (L) and Ivan Perisic sprint during practice at the Bundesliga club's training camp in Bad Ragaz, Switzerland, 24 July 2012. The German soccer club prepares for the Borussia Dortmund's players Mario Goetze (L) and Ivan Perisic sprint during practice at the Bundesliga club's training camp in Bad Ragaz, Switzerland, 24 July 2012. The German soccer club prepares for the](https://c8.alamy.com/comp/D68Y66/borussia-dortmunds-players-mario-goetze-l-and-ivan-perisic-sprint-D68Y66.jpg)