EBO2 (EBOO) for Athletes and Recovery: Hype, Anecdotes, and Evidence

EBO2 (also called EBOO) has become one of the more visible alternative therapies in professional sports after Philadelphia Phillies star Bryce Harper publicly described undergoing it during his 2025 to 2026 offseason. Athlete use is now a significant part of how the treatment is marketed to the general public, alongside claims about recovery and performance similar to those made for people managing long COVID symptoms. This guide separates the athlete anecdotes from the anti-doping rules and the actual research record on ozone therapy and physical performance.

Why athletes are the face of EBO2 marketing

In December 2025, Harper posted on Instagram that he had undergone EBOO, describing a process in which roughly a third of his blood was drawn, passed through a filtration and oxygen/ozone exchange device, and returned [3], and crediting it with improved circulation, reduced inflammation, infection resistance, immune support, toxin removal, and increased energy [1]. Harper, in his early thirties with years still remaining on a long-term contract, framed the treatment as part of an effort to extend his playing career into his forties, an angle sports outlets picked up alongside the procedure’s novelty [1]. The announcement was widely covered by sports media, and clinics marketing to athletes now routinely cite this kind of high-profile use as informal validation, alongside claims that EBO2 offers a competitive edge, enables faster healing after training or illness, and functions as a strategic upgrade athletes can schedule between training cycles [8][9]. One clinic recommends 4 to 6 sessions per year for athletes or others under heavy physical stress, a cadence presented as routine maintenance rather than treatment for any diagnosed condition [9]. A single well-known athlete’s public endorsement is a powerful marketing tool precisely because it looks like evidence without being evidence, a distinction worth making explicit before going further.

What the anecdotes are and are not

Harper’s account, and similar accounts from other athletes, describe a subjective experience and a list of claimed benefits, not a measured outcome. There is no blood test, performance metric, or blinded comparison attached to a celebrity’s account of how a treatment made them feel, and elite athletes make simultaneous changes to training, sleep, nutrition, and other recovery practices in an offseason that make it impossible to attribute any change to one intervention from an anecdote alone, even setting aside that Harper described the treatment before his next season had even started. Sports journalists covering the Harper story were themselves careful to separate the two: reporting noted that the FDA does not approve ozone therapy for any medical use and warns it may do more harm than good, while also noting no evidence Harper violated any league rule [2][3]. Celebrity use signals that a treatment is trending, not that it works, and ozone therapy is not FDA-approved for any medical use, including athletic recovery or performance [10].

Anti-doping status: what WADA says about blood manipulation

Ozone therapy, EBOO, and EBO2 are not named anywhere in the World Anti-Doping Agency’s 2026 Prohibited List [6]. That absence is not the same as a clearance. The list’s M1 category, Manipulation of Blood and Blood Components, prohibits, among other things, the administration or reintroduction of blood or red blood cell products into the circulatory system and the withdrawal of blood or blood components, including by apheresis, unless performed for analytical purposes such as medical tests or doping control, or for donation purposes at an accredited collection center, and separately prohibits, under a distinct clause, any form of intravascular manipulation of the blood or blood components by physical or chemical means [6]. EBO2 withdraws blood and reinfuses it after physical filtration and ozone exposure, activities that sit close to this wording without WADA ever addressing the specific procedure by name. This guide is not in a position to declare EBO2 banned or exempt under a rule written for other methods; the accurate statement is that the wording is broad enough to raise a real question, and any competitive athlete subject to WADA, national anti-doping, or league-specific rules should confirm the status of this specific procedure with their sport’s anti-doping authority before a session rather than assume a therapy not named on the list is automatically permitted. Major League Baseball’s joint drug program bans substances and methods that provide an unfair competitive advantage, and reporting on Harper’s case found no indication that EBOO is treated as a prohibited method under that program or that he violated any league rule [2][3]. MLB’s rules are, however, separate from WADA’s and do not resolve the question for athletes governed by Olympic sports, national anti-doping organizations, or international federations that follow the WADA Code directly, a much larger group of athletes than professional baseball alone.

Evidence for ozone and performance or recovery

Published human research on ozone therapy and athletic performance or recovery is minimal, and none of it involves EBO2 or continuous blood filtration. The most directly relevant human study is a small trial of 15 competitive cyclists comparing sports massage using ozonized oil against the same massage with plain oil after fatiguing cycling tests; the ozonized-oil massage was associated with a higher peak power output and lower perceived fatigue on a subsequent test than passive rest or massage with plain oil [4]. That is a topical application of ozonized oil during a massage, not a systemic blood treatment, and the trial enrolled only 15 male cyclists at a single university department, using three fatiguing Wingate cycling tests to induce fatigue before comparing recovery methods, a design that measured only acute post-exercise markers rather than any longer-term recovery or performance outcome. The closest data point involving ozone exposure of blood itself is not in humans at all: a study of ten Thoroughbred racehorses found that ozonated autohemotherapy increased a marker of antioxidant capacity in blood serum after treatment [5]. Extrapolating from ten racehorses to a human athlete, using an entirely different method than EBO2’s continuous filtration, is not a sound basis for a performance claim. No published trial has tested EBO2 or ozone autohemotherapy for human athletic performance, recovery time, or injury rates, in any sport, at any competitive level.

Recovery modalities with better evidence

Athletic recovery is a well-studied field, with decades of trial data behind its major modalities, and the contrast with ozone therapy’s evidence base is informative. A 2025 systematic review of post-exercise recovery strategies in soccer players, following PRISMA methodology across 41 randomized or crossover trials, found consistent benefit for cold-water immersion on jump performance and perceived fatigue, with positive but more variable evidence for active recovery, compression garments, sleep interventions, and nutritional supplementation [7]. Sleep duration and quality, structured training-load management to avoid sudden spikes in volume or intensity, and adequate protein and carbohydrate intake around training sessions all have a substantially larger and more consistent evidence base behind them than any ozone-based treatment, at a fraction of the cost and without an IV. None of these carry an anti-doping question, a consideration that matters for any athlete who competes under a code that follows the WADA list.

Risk-benefit for a healthy population

Unlike the other conditions in this series, athletes considering EBO2 are typically not sick; they are healthy people seeking a performance or recovery edge. That changes the risk-benefit calculation in a specific way: a healthy person has more to lose from a low-probability complication of repeated IV access relative to a plausible benefit that has not been measured in any trial, and less to gain from a treatment aimed at inflammation or toxin load when no deficit in either has been established in the first place. Combined with a session cost that runs from several hundred to well over a thousand dollars, a recommended cadence of several sessions a year for those who adopt it as routine maintenance, and the anti-doping ambiguity described above, the honest accounting for a healthy athlete is a real, recurring cost and an open regulatory question set against an evidence base that does not yet include a single published human performance study. A recreational athlete outside any anti-doping program at least avoids the eligibility question, but still faces the same recurring cost and the same absence of a human performance study to justify it, whatever a celebrity endorsement might imply about its value.

Bottom line

A prominent athlete’s public use of EBO2 is a real event and a genuine marketing driver, but it is an anecdote, not a study. WADA does not name ozone therapy or EBOO on its 2026 Prohibited List, but its blood-manipulation rules are written broadly enough that a competitive athlete should check with their anti-doping authority before a session rather than assume it is automatically permitted [6]. The human research most directly related to ozone and physical performance is a small trial of topical ozonized-oil massage in cyclists [4], and the closest data on ozone exposure of blood itself comes from ten racehorses, not people [5]. Athletes looking for recovery gains with an actual evidence base behind them have well-studied, far cheaper options in sleep, training-load management, and nutrition [7] before considering an unstudied procedure carrying real cost and an unresolved anti-doping question. For general background on the procedure itself, see what EBO2 is, this site’s clinic directory for how it is marketed and priced, and the cost guide for typical session prices.