Stacey DL, Gibala MJ, Martin Ginis KA, Timmons BW. Effects of recovery method after exercise on performance, immune changes, and psychological outcomes. J Orthop Sports Phys Ther 2010;40(10):656-65. http://arcticblastcryo.com/wp-content/uploads/2016/01/Immune-Cell-and-Decreased-Pain.pdf
Stenson MC, Stenson MR, Matthews TD, Paolone VJ. 5000 Meter Run Performance is not Enhanced 24 Hrs After an Intense Exercise Bout and Cold Water Immersion. J Sports Sci Med 2017;16(2):272-279. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5465990/pdf/jssm-16-272.pdf
Roberts L, James L, Caia J, Wellington B, Scott T, Halson S, Kelly V. Effects of external counterpulsation therapy on acute recovery in elite Australian rugby league players. Journal of Science and Medicine in Sport 2017; 20:Supplement 1,e85. http://www.jsams.org/article/S1440-2440(17)30045-2/fulltext
Maybe the position statement of the International Society of Immunology exercise could help you. Link: Article Position Statement Part one: Immune function and exercise
Hello Nathan Cazard I share with Eduardo Freitas that in your question some background is missing, such as; the type of intense exercise, the type of sport that athletes practice, the age of the athletes, the conditions in which the maximum effort is executed, etc. and of course, what do you consider as intense?