What the research says — and where it stops.

A 2020 meta-analytic review of 139 studies and 3,599 participants found that music was associated with improved affective valence, better physical performance, reduced perceived exertion, and changes in oxygen consumption during exercise and sport. This is the strongest evidence CHRP rests on, and it is peer-reviewed.

Published in Psychological Bulletin, it is a synthesis rather than a single trial, which is what makes it useful: the effect direction holds across many independent studies rather than resting on one result that might not replicate.

One limit worth stating plainly, because it is easy to skip: this evidence comes from exercise and sport populations. CHRP also works with military and workplace groups, and this citation does not extend to them on its own. Where the research has not gone, we say so rather than borrowing its authority.

There is a real and active research area — digital phenotyping — built on the idea that patterns in ordinary digital behavior carry meaningful signal about psychological state, but it is genuinely unsettled, and music listening specifically is less studied than phone-sensor or social-media traces.

This is the least settled of the three foundations and we would rather you hear that from us. The logic is sound: behavior a person produces anyway, at high frequency, without being asked, avoids the recall bias and survey fatigue that self-report carries. But “promising” is not “proven,” and reported effect sizes vary widely by population and signal type.

CHRP reads music listening behavior — what you play, when, in what sequence, and how that moves against your own baseline — and turns it into an EPI Score™ and playlists aimed at the state you are trying to reach. That is a description of how the product works, not a research finding, and the distinction matters.

No peer-reviewed validation of CHRP's own model exists, and we do not claim any. What the literature supports is the channel — that music is a real lever on how people feel and how hard effort feels. What CHRP adds is a way to read the lever you are already pulling. Whether it reads it well is a question we are still answering, in product, with real users.

CHRP's claims sit at four distinct strengths — peer-reviewed, emerging, how the product is built, and founder conviction — and the table below states which is which for every claim on this site. Nothing is presented as stronger than the strength recorded here.

The two lower tiers are not filler. “How CHRP is built” means a true statement about the product that no citation can support, because it is design rather than discovery. “Our conviction” means exactly that — an idea we believe and have not proven, which under our own governance may never be dressed up as research.

A gap worth naming: the Scientific Foundation behind CHRP runs to 29 references, and only the meta-analysis above is published here with a citable DOI today. Claims drawing on the rest are capped at “emerging” until their specific references are published — not because the underlying literature is weak, but because a claim you cannot check is a claim you should not have to take on faith.

Flow is a belief we hold, not a finding we cite. We think music can act as a trigger for the shift into a focused, absorbed state, and that belief shapes how CHRP is designed — but there is no flow-cycle source in our research corpus, and we will not present it as though there were.

It appears here rather than being quietly dropped because a reader deserves to know which parts of a company's thinking are evidence and which are conviction. This one is conviction.

CHRP does not diagnose, treat, or cure anything, does not determine fitness for duty, and does not guarantee a competitive outcome. The full list is below, and it is a standing boundary rather than a legal footer.

Emotional Performance Intelligence is a performance category, not a medical one. Reading how someone listens is not the same as assessing their health, and CHRP is built so the two can never be confused — by a user, a coach, or an organization.

• CHRP does not diagnose, treat, or cure medical or psychological conditions.
• CHRP does not determine fitness for duty or inform employment decisions.
• CHRP does not infer precise emotional states with clinical-grade accuracy.
• CHRP is not a substitute for licensed clinical, psychological, or medical care.
• CHRP does not guarantee a competitive outcome or a specific performance gain.
• CHRP does not publish peer-reviewed validation of its own model, and does not claim any.

CHRP rests on three ideas — that music is a real lever, that behavior carries signal, and that a model can connect them — and they are load-bearing in that order, from strongest to least settled.