The evidence standard

What sits under every recommendation

Most programs tell you what to do. A few mention research. Almost none show you which trial, who was in it, or whether the people studied looked anything like you. That last part matters more than anything, because a great deal of exercise and supplement research was run on young men.

So here is the block. It appears beneath each recommendation, and it never changes shape.

Two separate questions, two separate labels

Every recommendation gets judged twice, because there are two different ways research can let you down.

The first question: how good is the study? A finding from one small eight-week trial is not the same as a finding confirmed across a dozen trials involving thousands of people. That's what the Grade tells you.

The second question: were the people in the study anything like you? A great deal of exercise and supplement research was done on young men, or on college athletes, or on patients already sick with something. A study can be excellent and still tell you very little about a healthy 62-year-old woman. That's what the Fit tells you.

A recommendation can score well on one and badly on the other. That's why both labels appear, and why neither one alone is the whole picture.

Grade — how good is the study?

Strong — the same result showed up in several separate randomized trials. When different research teams keep finding the same thing, it's probably real.

Moderate — one good trial, or a few small ones. Likely real, not yet nailed down.

Preliminary — early research. A small group, a short study, or one that measured a stand-in rather than the thing you actually care about. Worth knowing about. Not worth building your week around.

Fit — were they like you?

Matched — the study was done on women in roughly your age range. This is the gold standard, and it is rare, because far less research has been done on us.

Partial — the study included both men and women, or people somewhat older or younger. Close enough to be useful, with the gap named.

Mismatched — the study was done on a group quite different from you: young men, athletes, or people with a specific illness. The finding may still apply, and when I use one of these I explain why — usually because the same effect has since turned up in a group closer to you.

How that looks in practice

Take the interval training example above. The original study was excellent — randomized, well run, and its finding has been repeated many times over. So it earns a Strong grade.

But it was done on forty men averaging 24 years old. On fit, that's Mismatched. It's still in the protocol because the same benefit has since been found in men and women in their seventies — and that follow-up study is named right there in the block, so you can check it yourself.

Anything resting only on animal studies or laboratory work gets no block at all. If it appears in a protocol, it's labeled as reasoning rather than evidence, and it's kept rare.