The science · Racing

The taper: why training less before a race makes you faster

The hardest instruction in any race plan is the last one: do less. After months of building, easing off feels like throwing fitness away. The physiology says the opposite — the final weeks are where fitness stops being masked by fatigue.

Race already in the diary? Two minutes, free, no account.

What the research says

Training leaves two things in your body at once: fitness and fatigue. Performance on any given day is roughly the gap between them (the classic fitness–fatigue model). In the final stretch before a race, extra training adds little fitness but plenty of fatigue — so the winning move is to shed fatigue while preserving the adaptations you've built.

Bosquet and colleagues' meta-analysis of taper studies in endurance athletes put numbers on it. The most effective pattern:

• Reduce training volume by roughly 40–60%,
• over about two weeks (one to two, depending on the block behind you),
• while maintaining intensity and training frequency — short, sharp touches keep the systems primed.

Typical performance improvement from tapering properly is small in percentage terms — on the order of 1–3% — but at race pace that's minutes over a half-marathon, and it's the cheapest gain in the entire plan.

Taper rules of thumb

• Cut length, not sharpness: sessions get shorter; strides and short race-pace efforts stay.
• Nothing new in race week: no new shoes, foods, or heroic final workouts. The hay is in the barn.
• Expect to feel strange: restlessness and phantom niggles are common when volume drops. They're withdrawal, not detraining.
• Sleep is training now: the adaptation you're waiting for happens at night.

Related: Goals that get done · Streaks break people · Why tracking works