Pretty much what I was expecting. BBC also have an article, altho that Guardian one includes more insight I think.
Interesting that they’ve quantified the purported benefit of the alphaflys. Double the original vaporfly!?!
Magic shoes = revised goal/training paces?
I’m sure this will have been discussed before.
Putting it in the simplest of terms, if I’m training for a 4h mara, do I subtract 4% and set off at the revised pace or what?
No, you’re the first. I would stick to what you’re doing; if the shoes are magic, then a you’ll reap the benefit on race day. They never claimed to improve time by 4%.
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I don’t get this distinction between economy and speed.
If I think of running power (which I don’t have but bear with me) and I’m putting out 200W to do 8min/mile then if my economy improves by 4% I can put out 4% less watts to go the same speed or I can still put out 200W and go 4% faster.
Is Nike’s quoting of economy rather than speed just to avoid being sued by everyone who didn’t go 4% faster as it’s a more vague/obscure metric?
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I think this RW article explains it, and the NY Times article that supports it (where they analysed thousands of race results on Strava). While Nike may not have made the claim, and that economy wont always translate into speed, they’re all saying you’re going to run faster…around 4% faster.
So far my testing suggests it feels easier, lower HR. But I can’t really fit in two comparable 5k races into my training plan. I could compare 1600m reps tonight, but I reckon the margins are too small to rely on…I’m say aiming at 7:20 per 1600…so 440s… if I was a perfect pacer (and I’m shambolic)…4.4sx4…17.6s faster…so that would be 7:20 (pegasus), 7:02.4 (magic), 7:20 (pegasus). Oh, so maybe a noticeable difference, no harm in trying.
“relationship between improvement [in running economy and speed is not linear”
“a 4-hour marathoner who saves 4 percent energy will run 4 percent faster (9 minutes and 36 seconds, or a 3:50:24 marathon), whereas a 2-hour marathoner will run only about 2.5 percent faster (3 minutes, or a 1:57:00 marathon).”
Other than the non-linear relationship, which makes sense, this does seem to back up that economy does result in a similar increase in speed for the same level of exertion but other factors come into play as you go faster such as aero, hence the shield of runners at the sub 2 attempts.
That’s not how running power works, which is largely why it’s still so questioned.
On the bike, every watt of power a power meter measures is going into the cranks (if measuring at that point). When running, power being exerted on the ground can get dissipated in a number of different ways - into wasted vertical oscillation, lateral stabilisation, etc, as well as forward propulsion. As I understand it, running economy is a combination of those factors. Stryd outputs total power but also form power. You want the latter to be as low as possible, as that’s the power being wasted just keeping you upright. Generally, as you fatigue, form power increases.
As your follow up post implied, better runners have better running economy to begin with, in order to be that good. Therefore, a 4% increase for them will be much less impacting in time gained than a 4% increase in someone who haemorrhages effort in just staying upright. But, at the pointy end, seconds here and there can be all the difference, so in that sense it’s no less important.
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Well, well, well.
So your not going to believe this, I surprised myself that’s for sure. I couldn’t see my pace, but my 1600m times came in as…
7:08 (Pegasus), 6:45 (Nike 4%), 7:08 (Pegasus)
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@joex what about your HR for each effort?
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Good point.
I’m not sure this means much though, HR increased each interval. HR was higher with second interval, the 4%, but higher again on the third which was the same pace as the first… so I suspect that’s just saying I had to work harder each time regardless of the shoe.
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Seems fair enough and on the face of it a really good improvement in the magic shoes 
That sub 4 marathon is a shoe in for you now 
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What could go wrong? 
Even without the magic, the RLRF protocol takes my 7:08 1600 times in the Pegasus 35s and predicts a 3h43 marathon target. So yes, I’m feeling a lot more confident of breaking 4h. 
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What’s the rlrf protocol? Because doing 3 x mile reps doesn’t sound like a good marathon predictor in all honesty. It’s like the yasso 800s, totally different energy systems.
Though it’s really positive to see your obvious progress. Keep it up.
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They made the BBC breakfast news this morning, even cut open a pair of 4%'s with a water jet cutter.
RunLess Run Faster, the Furman FIRST marathon programme.
Run 3 times per week (Intervals, Tempo, Long - no easy running at all), +2 hard cross training, +strength training.
I’m nattering about it in the Sub 4 marathon thread 
I was wearing my Pegasus pinkies to Tri club swim this morning, they were mistaken for Vapes.
The knowledge about the shoes with the general public is sparse.
Brexit, Premier League, Love Island, Good Morning, Mail Online, Corrie, Crapenders, Dominoes Pizza…that is general.
We don’t do ‘General’
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Just watched it back on iPlayer. Its at 6.35 for anyone else.
Bit of a stupid segment. All the statements go against what the BBC themselves are reporting. They spent the entire time talking about the NEXT% and 4% being banned, despite every source saying that’s not going to be the outcome. I guess it’s hard to make a segment on the alphafly being banned if you don’t actually have a pair you can cut up.
And they focused entirely on the carbon plate. Which loads of shoes have.
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Yeah, I saw that before I came out this morning. Thought the whole piece was pretty pointless, clearly no-one involved in the discussion had the slightest clue what they were talking about. I’ve never seen that sports reporter before so maybe she’s a stand-in and Naga just likes to have the last word on everything. Charlie just sat there looking bemused.
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Not that she writes the stories, but Sophie Raworth just won an England Masters vest at the Farnborough half (2nd in AG, 1:34…she is 51 
!). She posted a picture of her running she had some 4%s on (guy next to her had pink Next%s), so she, at least, has some knowledge about them 
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