How long do gels take to kick in?

Got my gels for London this weekend, I use them in training and im fine with them however ive got some new 50g of carb ones, the zipfit ones isnt it, anyhow how long in general do gels take to kick in, 1 mile, 2 miles, 30 minutes etc?

 Thanks

Aside from initial sugar boost 30 -60 min depending on the individual what else you've eaten etc.
Wouldn't recommend using new gels on the day, stick to ones you are used to.

Don't use gels you haven't used before! For all you know your digestive system can't cope with these particular gels (which sound quite high carb - High 5 are only 20g carbs/gel) and you'll end up doubled over with stomach cramps by 10M. Stick with the gels you've used in training and save these new ones for whatever your next long distance training event is.

I generally take a gel every 4-5 miles and in general terms anything you take after about 22/23 miles is likely to have only a placebo effect.

I've heard it's about 20 minutes or so. But if you feel the need for a "kick" then I think it's too late other than for the placebo effect.

Like Joolska intend to take them every 4/5 miles so never feel like I'm waiting for them to kick in, rather I'm just topping the carbs up.

I've also heard they take around 20 mins.

I'm with the 4/5 mile brigade too I never feel them "kick in" as it were but I know that if I don't take them I'll suffer by about mile 17. High5 claim that there's no point in taking one 20mins from the end so I guess that means they take about that time to work. As others have said, don't try anything new on the day, including gels. The Zipvit ones are good in that they have pretty much an hour's carbohydrate in one pack but you need to be sure that you can eat one pack in one go without tummy trouble. You may find 2 separate packs of a lower carb-quantity spaced out by say 30 mins much easier to digest and they will still give you the amount of extra carbs you need.