Changes

<ref name="Cooper1968">{{cite journal|last1=Cooper|first1=Kenneth H.|title=Cooper, A Means of Assessing Maximal Oxygen Intake<subtitle>Correlation Between Field and Treadmill Testing</subtitle>|journal=, JAMA: The Journal of the American Medical Association|, volume=203|, issue=3|year=, 1968|, pages=201|, ISSN [http://www.worldcat.org/issn=/0098-7484 0098-7484|], doi=[http://dx.doi.org/10.1001/jama.1968.03140030033008 10.1001/jama.1968.03140030033008}}]</ref><ref name="Billat-1996"> {{Cite journal | last1 = Billat | first1 = LV. | last2 = Koralsztein | first2 = Billat, JP. | title = Koralsztein, Significance of the velocity at VO2max and time to exhaustion at this velocity. | journal = , Sports Med | , volume = 22 | , issue = 2 | , pages = 90-108 | month = , Aug | year = 1996 | doi = | , PMID = [http://www.ncbi.nlm.nih.gov/pubmed/8857705 8857705 }}]</ref><ref name="Léger-1984">{{Cite journal | last1 = Léger | first1 = L. | last2 = Mercier | first2 = Léger, D. | title = Mercier, Gross energy cost of horizontal treadmill and track running. | journal = , Sports Med | , volume = 1 | , issue = 4 | , pages = 270-7 | month = | year = | doi = | , PMID = [http://www.ncbi.nlm.nih.gov/pubmed/6390604 6390604 }}]</ref>