Why do sprint­ers drag their toes?

DO SPRINT­ERS NEED TO WEAR OUT THE TOES OF THEIR SPIKES?

Athletics Weekly - - Contents -

IF YOU’RE a sprint coach you’ll know what we’re re­fer­ring to here. There’s a ten­dency – which is a re­flec­tion on the way the sprint start can be coached nowa­days – to toe­drag on the block clear­ance. Specif­i­cally, the toes of the rear leg catch the track as they pull through into the first step.

The toe-drag is a con­se­quence of the sprinter keep­ing their foot low to the track sur­face in or­der to get it to move more quickly from A-B or specif­i­cally from rear block to track con­tact on re­ac­tion to the gun. If the heel is picked up the foot will “loop” to the front – there will be more air time and it’ll slow the start.

The toe-drag method has also been seen to place the sprinter’s dis­place­ment in a su­pe­rior po­si­tion – or more specif­i­cally, an­gle where force can be bet­ter ap­plied. Af­ter that ini­tial step of ac­cel­er­a­tion, heel re­cov­ery is usu­ally also kept low too – again to min­imise air time and to po­ten­tially al­low the ath­lete to im­part more force onto the track sur­face and pro­duce greater ac­cel­er­a­tive speed – of which more later.

Many elite ath­letes have been us­ing the toe-drag lowheel re­cov­ery tech­nique for years – such as Asafa Pow­ell, Marvin Bracey, Trayvon Bromell and Usain Bolt.

We did some re­search on one of the world’s largest sports science re­search data­bases and could not find a spe­cific ref­er­ence to “toe-drag, low heel re­cov­ery and sprint ac­cel­er­a­tion/sprint start” (or sim­i­lar), how­ever, we did find some re­search that seems to vin­di­cate the low heel re­cov­ery and toe-drag start method.

Re­searchers in Sports Biome­chan­ics “mod­elled” sprint ac­cel­er­a­tion vari­a­tions from the sprints per­formed by a 10.28 sprinter, it was dis­cov­ered that in­creas­ing the range of foot plan­tar-flex­ion (toe-down) in­creased power pro­duc­tion. (This may be at odds with some thoughts on foot po­si­tion but it is be­yond the scope of this ar­ti­cle to go into spe­cific de­tail).

Ralph Mann – one of the world’s fore­most track & field biome­chan­ics ex­perts – has in­di­cated that shorter steps dur­ing ini­tial sprint start ac­cel­er­a­tion are bet­ter than longer more force­ful “held/ push­ing” ones. The re­search pre­vi­ously quoted can be used to back this up in that when the foot was moved fur­ther back un­der the sprinter’s cen­tre of mass ac­cel­er­a­tion was im­proved (and as in­di­cated the toe-drag can help that es­pe­cially on the first step from the blocks).

Note, this is to a point – as the re­searchers in­di­cated: “When the foot was placed fur­ther back, power pro­duc­tion ini­tially in­creased (a peak in­crease of 0.7% oc­curred at 0.02m fur­ther back) but de­creased as the foot con­tin­ued to touch­down fur­ther back.”

Many sprint­ers and coaches will have learnt to drive away from the start and may ques­tion the va­lid­ity of shorter steps (al­beit slightly shorter), how­ever, the fastest ac­cel­er­a­tors tend to be the ones who can move their legs the fastest and im­part the most force at the same time while trav­el­ling an op­ti­mum dis­tance per step.

What may well be the hid­den in­gre­di­ent – ev­ery­thing else be­ing equal – is the rate of force pro­duc­tion on those quick, low heel re­cov­ery ac­cel­er­a­tive strides.

As power is a prod­uct of ve­loc­ity and time, if the foot strikes the ground more quickly and po­ten­tially in a su­pe­rior po­si­tion (through greater dor­si­flex­ion and toe-drag on the first step) to gen­er­ate that force then the ath­lete will move quicker. And it seems then that spikes may be worn out at the toe in the process.

The above is in­tended to il­lus­trate thoughts on sprint­ing and should not be seen as be­ing de­fin­i­tive.

A fast start will likely lead to a fast fin­ish

Drag­ging the toe on block clear­ance may pro­mote faster starts for a sprinter

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