Normative Yo-Yo Intermittent Recovery Level 1 and Yo-Yo Intermittent Endurance Level 1 test values of boys aged 9–16years - Journal of Science and Medicine in Sport
Yo-Yo tests - footballscience.net | Soccer, Football, Training, Testing, Recovery, Injury Prevention, Conditioning and other interesting topics
Should you do Level 1 or Level 2 Yo-Yo Test?
I Test di valutazione funzionale : Yo-Yo Intermittent Recovery Test
Yo-Yo Intermittent Recovery Test - Ultimate Soccer Fitness | 5-a-side.com