Does exercise reduce porn urges?

This is borrowed evidence, and the borrowing needs saying first. Everything measured here was measured in people quitting cigarettes or in drug treatment. Not one study has taken a pornography urge, applied exercise, and measured what happened to it.

What the trials found

Roughly forty trials and four independent meta-analyses agree on direction: rate your craving, exercise, rate it again, and the second number is lower. They disagree sharply on size. Pooled estimates in temporarily abstaining smokers are very large — standardised mean differences of −1.91 and −2.03 in the individual-participant-data meta-analysis, and weighted mean differences of −1.90 and −2.41 in the 2012 review update. The most recent network meta-analysis puts the acute aerobic effect at −0.23, roughly an order of magnitude smaller, and grades the whole body of evidence low certainty.

Both numbers come from the same kind of study, and it is worth knowing what kind. Every trial is unblinded, and the outcome is a self-reported urge rating collected minutes after an intervention the participant knows they received. Expectancy is ruled out nowhere in this literature. An effect the size of −2.0 for a short walk is a reason for caution rather than confidence.

How long it lasts

Where duration was measured, the drop peaked during or just after the bout and was gone within thirty to fifty minutes. That is the useful, unromantic shape of the finding. It is a way through the next half hour, not a way of having fewer urges.

How much of it

Less than you would guess, which is worth saying plainly because it removes the excuse. Reductions turned up at intensities from 24% of heart-rate reserve for fifteen minutes, and from five minutes of isometric exercise, up to 80–85% of heart-rate reserve. Intensity cuts differently for mood, though: light-to-moderate exercise lowered negative affect while vigorous exercise raised it during the bout. If the urge is riding on a bad mood, hard intervals may be the wrong instrument.

What it does not do

It does not improve your chances of stopping. In smoking — the only behaviour where this has been followed all the way to a cessation endpoint — a review of cessation trials found that adding exercise did not move the behaviour at six months. A craving that drops for thirty minutes and a behaviour that changes over six months are not the same result, and this is the clearest demonstration anyone has of that gap.

On pornography specifically

Three papers exist and none of them measures an urge. One is a four-study paper whose group exercise programme did not significantly reduce problematic use; what it did was stop it rising, which it did do in the untreated control group. The other two are cross-sectional surveys of a single sample of 600 adults, in which regular exercisers scored lower on problematic use — and one of those found exercise cutting both ways, weakening the path from unmet psychological needs to coping motives while strengthening the path from coping motives to problematic use. That is the one porn-specific result that does not point the friendly way, and it is a survey.

The comparison worth holding on to

The other in-the-moment tactic anyone has tested is urge surfing. In Bowen and Marlatt's 2009 randomised study of 123 undergraduate smokers, brief urge-surfing instructions did not reduce reported urges at all — and did reduce smoking over the following seven days. Exercise is the mirror image: it moves the number, and at six months it does not move the behaviour. Neither has been tested on pornography, and anyone presenting either as a demonstrated technique for a porn urge is asserting past the evidence for both.

One thing is settled about the next half hour either way. Pushing the thought away is the move with a rebound behind it: suppressed sexual thoughts increase.

Where this comes from

Read the full lesson: Sleep, exercise, and the boring foundations →