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.

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.

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