The 400m running track: lanes and staggered starts

A standard 400m running track has eight lanes, each 1.22 metres wide, and two straights of 84.39 metres joined by two bends. The 400 metres are measured in lane 1, along a running line 0.30 metres out from its inner edge. Because every outer lane is longer through the bends, each one starts ahead of the lane inside it: that is the staggered start. This guide explains the 400m track and why its start lines look like a staircase.

The shape of a 400m track

A track is a loop of two parallel straights and two half circles. Each straight is 84.39 metres long, and the radius of the bend at the inner edge of lane 1 is 36.5 metres. Put together, the two bends make one full circle along the running line, and the straights make up the rest of the 400 metres.

Lanes, and how they are measured

Each lane is 1.22 metres wide. Runners do not run on the inside line itself, so the distance is measured along a running line: in lane 1, 0.30 metres out from the inner edge where there is a kerb; in every other lane, 0.20 metres out from its inner line. Measured that way, one full lap of lane 1 is exactly 400 metres.

Why staggered starts?

If everyone started from the same line, runners in the outer lanes would cover more ground, because the half circle of each bend grows as the lane moves outward. The answer is to start each lane ahead by just enough to cancel the difference, so every runner covers exactly 400 metres.

In a 400 metres race, lane 2 starts 7.04 metres ahead of lane 1, and the runner in lane 8 starts about 53 metres ahead. That is why the outer lanes seem to lead early on, and the real order only shows once the field comes off the final bend.

Where does 7.04 metres come from?

The maths is short. In a 400 metres race the runner covers both bends in full, which together make one whole circle. The running line in lane 1 is 0.30 metres out from the inner edge; in lane 2 it is 1.22 + 0.20 = 1.42 metres out from that same edge, so 1.12 metres further out. A circle's length grows by 2π times that difference: 2 × 3.1416 × 1.12 ≈ 7.04 metres.

Every lane after that sits a further 1.22 metres out, adding about 7.67 metres per lap each time, so the gap builds up to roughly 53 metres by lane 8.

Off the bend, into the straight

The moment the field comes off the bend into the home straight is where The Bend comes from. A small stitched mark of the bend, two lane lines curving under an orange finish line, sits at the chest of tees, crewnecks, hoodies and a mesh jersey. On the back of the tee and the front of the tank, a crayon lane 4 card and a stopwatch carry the line “LANE 4, ALL THE WAY ROUND.”

The track on our pieces

Plate III: 400 m Track is a crayon view from the stands over the red bend of the track, with the line “400 M.” underneath, on paper, canvas or metal.

For the long-distance runner there is the embroidered Long Run figure: bib pinned, knee up mid-stride. Every running piece is in the running collection, and each one is made for you after you order, with free shipping.

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