Transition to racing flats

What's your reasoning for wearing flats?

Someone like Rinny can get away with flats in an IM run (and her NB "flats" aren't really flats in the typical sense) because she runs really fast.  If you can run a 2:50 IM marathon then have at it.  If you plan on running for 4-6 hours then a running flat would more than likely be a complete disaster.

Pros: lighter, which in theory allows for quicker turnover, which in theory allows for a faster run.

Cons: Almost no cushioning.

That con will generally outweigh that pro.

I tend to agree with this.  I do wear flats, but only for races below 10K... but I can get away with it for the most part... I race at ~ 130 pounds, I have a track running background, and I have a fairly "light" step and running form.

Fixed it for you........but agree with your premise and I know some folks use them for speed work.

I suspect the OP wasn't actually talking about racing flats, but more likely zero drop shoes.

Just curious....why?

They are pretty dang close to flats at, I believe, around 6oz. Definitely agree with the marathon time part and weight of the athlete definitely comes into play as well. I race in flats (NB MRC1600 previously) and sometimes would use them for shorter speed work on the track but not always. Definitely not a shoe you want to do all your daily mileage in. If you're not a clyde then give them a try on a 5k and see how they go, you can build up from there if all is well. 

I get that, but we just use racing shoes for racing, flats or spikes.  While I agree that racing shoes are not durable enough to put a bunch of miles/wear on them, I don't agree that wearing them in training gives you any benefit.  In fact, I would argue that only wearing them in races is where the real benefit comes from because of the difference between them and training shoes.

I have raced in flats from 3K to the marathon. I do not do any training in them with the exception being a quick race simulation to make sure everything feels right before a marathon. 

The biggest pro to the flat of course is their lightweight nature. Mine are something like 2.4 oz. (I don't wear these for the marathon distance, those are something like 6 oz)

But likely for most there are more cons than pros. If you need/like any kind of support or cushioning, they really aren't for you. Also, if you are managing any kind of injuries, they will likely exacerbate them. If you are a heavier runner or even have a heavy gait (if that makes sense) they probably aren't for you. You just have to think, if the shoes aren't absorbing any of the shock, it's your body that is. So, the question is, can your body handle that or not?

I definitely would NOT wear them for training. 

I only pretend to be a runner.  But my racing flats stay on the shelf except for 10k races or shorter.

I dabbled with Vibrams for some short workouts and track work just to get a feel for flats and try that theory/style of running...

For Half mary or longer (and their counterpart lengths in tri) I love my nice cushiony running shoes.

Yeah, that's a big difference.  Flats and zero drop shoes are not the same thing.  In fact the Rinny shoes you mentioned in your OP are 6mm drops and not zero.

There are plenty of low drop shoes (0-4 mm) with plenty of cushioning.  Most of the Hoka shoes fall within the 2-4mm drop and they're super cushioned.  Altra has the Olympus which is a zero drop cushioned shoe.

Zero drop is a farce. If you really think you need to work on landing more midfoot (how did you come to decide you even need to?) then take your shoes off, get in the grass and start running some strides barefoot. 

I completely agree.

And even then, messing with your stride really should be something that is monitored by an expert.

Proceed with extreme caution.

For me there has been, but your mileage may vary.