devashish_paul wrote:
But 4W per kilo for a 75 kilo athlete gets you a lot faster to T2 than 4W per kilo for a 62 kilo athlete. Both have to push the same wheels from Kailua Pier to Hawi and back through the air, so its a higher percentage of the 62 kilo athlete's top line wattage.
Seeing as this thread has completely derailed - I'll throw in the below.
Perhaps warrants a separate debate, but in response to the above:
Will it really though?
Have you any data to back this up?
I've tried to get an answer on this and in my opinion it's not necessarily.
And this is still something I've looked at many data files to try and ascertain and still haven't got a final answer but don't completely agree with your statement.
How much do greater watts count in a similar w/kg bike split?
CDA is very important but assuming similar position and attention to detail?
The bigger athlete will always be punching a bigger hole in the Air and have a worse CDA as a result.
On a windy course like Kona, I think this counts for a lot more than you'd think.
Data points:
I know an athlete that raced Kona'16 in 4:29 (Bryan McCrystal).
Said athlete lead the Amateur race to that point with the fastest bike split by a mile.
He's very aero, but a big guy and pushes massive watts to get those times.
Pays attention to all the details and is an uber biker from an amateur perspective and up at leading pro class (now racing pro).
Anyway, it took him 3.6-3.7 w/kg to get that 4:29 and 325w.
https://www.strava.com/activities/741785301 I've been using Best Bike Split for a while now and it's coming in bang on so I've my CDA to a reasonable accuracy and updated with actual race files etc.
If I punch in Kona, with same date and time for advanced weather, and my CDA to return that bike split I get just over 3.6 w/kg.
Now clearly I can't hold 3.6 w/kg, but point being CDA counts for a lot more than you'd think and w/kg is a fair indicator for many.
Ok so this is only an estimate, but BBS hasn't been far wrong for me yet if at all and for most I think is a reasonably accurate estimator.
Even if we take a 5 minute margin of error - that's still pretty damn close and not a massive advantage for the bigger rider like you'd expect.
Kinda results in FTP and W/kg counts. Assuming relatively similar aero attention and position relative to the rider size.
So if a Pro is racing at 4 w/kg, and has relatively similar aero position then I'd expect the gap to be barely a few minutes regardless of weight and watts pushed.
Obviously there will be exceptions to this, but my point is that bigger watts doesn't always trump and w/kg can be a better estimate than you give credit for.
Now, to
counter my above data points:
Lange's file is also on Strava - and it states 248w or 3.93 w/kg.
https://www.strava.com/activities/740934179 Removing his 5min penalty would have returned a bike split of 4:33 - so 3mins slower than above but for an extra .3 w/kg if his power meter is accurate etc.
Lange is pretty aero though I'd class McCrystal as more aero with head being lower and having a better tuck so I'd explain this difference from aero position being weaker.
Another example in
favour of my points:
Ben Hoffman - 265w for 4:28 = 3.63 w/kg same as McCrystal for faster bike split... and similar aero position it appears but Hoffman is a good 15kg lighter...
https://www.strava.com/activities/740732530 Slowtwitch's favourite:
Lionel Sanders - 300w for 4:25 on 4.1 w/kg (73kg??) . Now clearly he isn't getting the same return or his power meter is off or he broke aero too many times.
So in summary, if we take Lange (exc 5min penalty), Hoffman and McCrystal for Kona'16 bike splits.
4:33, 4:28 and 4:29.
63kg, 73kg and 88kg.
248w, 265w and 325w.
3.9 w/kg, 3.6 w/kg, 3.6 w/kg
So sorry, but your statement of ultimate watts trumping w/kg doesn't ring true at all for Kona. Perhaps would a little more on a flat course with no wind. But thankfully that's few and far between.
And I'd argue that McCrystal has the best aero position and head tuck than all of the above - as seen in below pics also.
Pictures of position at Kona (isolated examples).
Lange:
http://www.slowtwitch.com/articles/images/8/152328-largest_151033-largest_KonaMbike20.jpg
Hoffman: http://professionaltriathlon.com/wp-content/uploads/2016/10/bike-ST-Krabel-480x297.jpg
McCrystal: http://i65.tinypic.com/m78gfa.jpg