Validity and reliability of speed tests used in soccer: A systematic review Altmann, Stefan ; Ringhof, Steffen ; Neumann, Rainer ; Woll, Alexander ; Rumpf, Michael C. Abstract Publication: PLoS ONE Pub Date: August 2019 DOI: 10.1371/journal.pone.0220982 Bibcode: 2019PLoSO..1420982A