I got as a gift proposition shoelaces before starting to do triathlons but I made the mistake of cutting them too short. I did not notice the blood circulation of my feet which being cut off until hours later one day I had to wear my tennis shoes the whole day. It was torture !! So When You first put them in your shoes, be sure to leave them super loose and adjust the size with your foot inside !! You will be surprised how much thesis laces tight.
So what I did was just I had to get a new pair and what more careful while cutting. They're really practical and pretty comfortable!