Specifically it is multisport atheletes that are looking at racing shoes in +Amphibian King Galway and asking this question and it is in relation to speedier transitions between the sports, usually bike to run phase where the speed laces are in the running shoes to save time in T2, though in duathlons this can be T1 and T2.
Whats so important about lacing?
To answer you need to be aware that the lacing of a running shoe is actually considered part of the structure of the shoes, its part of the 'upper' and works to help the shoe to wrap around your foot providing stabilising structure to the foot joints. (This is not the same 'stability' that you get from the midsole structures, different topic all together.)
Thus, the entire shoe as you unbox it is a complete system.
As triathletes / multisporters, we will inevitably swap out the laces in our shoes with elastic lock laces, typically of the type shown below.
You replace the standard laces in the shoe with the elastic type which you adjust so that they snugly hold the foot in place when closed, yet when released you can slide your foot into the shoe, hold the tap and slide the spring loaded lock down to lock the laces.
|Brooks ST 5 with Lock Laces|
There are a number of different systems and products on the market but essentially the elastic lace works by being flexible enough to allow the foot slide into the shoe quickly, without major adjustment.
Unless you are using a race specific shoe which you can leave the laces in and are using a separate running shoe for all your training work (with correct laces) I would advise changing the laces, learn to tie your laces really fast, or get yourself some speed laces of the non-stretch, non-elastic lace variety.
There is one brand which does this brilliantly, Greeper Laces. Greepers are normal, proper laces with a really nifty quick release and fastening system. They are the perfect balance between speedy transitions and getting the support and performance from your shoes.
Sure, you might lose a second in transition against the elastics, but you will more than make this back in terms of the performance on the run.
For me this year, I'm going to give the Xtenex a whirl on any of the Sprint triathlons I do but Greepers all the way for the standard through middle distance races.
The hard decision is which colour to pick!
Happy running :)