My first triathlon was in 2013 and I still don’t really understand the difference, physiologically, between running and cycling. What is it scientifically that is developed to attain ‘the run legs’?
Subjectively we’d probably say it’s time on feet, but does that develop smaller assistance muscles not used in cycling, or posture or…?
Not an expert.
One is impact the other isn’t. One is weight bearing requiring core the other isn’t. No idea if that makes a difference but marathons break you down in a way that the same time on a bike doesn’t.
I posted some of the differences before, not sure if on this forum though.
Running involves concentric, eccentric, and isometric muscle contractions, while cycling primarily involves concentric contractions. This difference means running involves more muscle damage (it also load baring) and can lead to greater muscle activation across a wider range of muscles, including the hamstrings, calves, and core, whereas cycling focuses more on the quads, glutes, and hamstrings and has lower impact and muscle damage due to the lack of significant eccentric contractions.
Cycling you have the bike to aid efficiency there is theorically less difference in economy between althletes where as running there is a larger difference in economy due to many factors, weight, tendon stiffness for example.
Time on feet helps with economy and as well as the normal ‘stuff’ *(can you tell I got bored with writting this towards the end, lol)
Okay, so do we think that muscle fibres adapt differently to those isometric and eccentric vs adaptations to concentric, contractions?
And so we think it’s the bigger groups that is the majority of difference, calves and core etc.
ok, cheers.
Also no expert & had 2 beers but think cycling is a strength sport, it’s about how much force you can apply, and how long you can sustain it within a closed range of motion.
Running is so different, it’s a grace sport, it’s about the timing and efficiency and lightness of movement - how little energy you can expend to move your body forward in an open-ended range of motion.
At the extremes this gives you Chris Hoy v Mo Farah type body shapes, but the GC climbers are perhaps sort of half of both. I reckon G could go out tomorrow and smash 3h including a stop for a Welsh Rarebit and some lava bread at halfway.
I’m not sure what you mean by “strength sport”, but cycling otuside the track is basically purely aerobic, everyone has pretty similar efficiency at cycling, so the person with the most energy delivered will win.
Running though has a huge range of efficiencies, people are extremely different - not just from “grace” but from actual physical differences, length of levers, length and springy-ness of achilles etc. We know that any pro endurance cyclist has the aerobic ability to be ~2:30 marathoner, but they could be so inefficient as to “only” be a 3:15 if extremely unlucky.
Maybe it’s a clumsy word & a long time since i did physics, but think in cycling you produce mechanical torque against the resistance of the pedals, with power = force × cadence. Need strength to produce force.
I’m sure you need it in running too, but also think running needs the other things you mention , more than cycling does at least ??
Switched to diet coke now btw
Friend asked if I fancy Barcelona marathon with him. I’d only managed 80km in the previous 7 weeks due to work/house, but it lit a fire under me despite only being 10 weeks away (and I’ll spend 2.5 weeks on holiday)
Felt inspired so I asked for a week to test some training - managed three decent sessions and now it’s sold out so there goes that motivation disappearing in the wind
Plenty of others 
Edinburgh, Paris 
Edinburgh only has £700 charity entries left. Kicked my motivation into touch too.
Entry via Sports Tours or such like? Or a charidee entry?
Noticed a few impressive sessions on Strava 
Get chased off lions 
Thanks Jeff,
Not sure where I have been, I think I moved computers and lost my common links, anyway, hi all 
yes 35th sub 3 on the bounce. I also managed to pull off my tenth consecutive year of
<2:50 marathon
<1:20 half
<18 parkrun.
Age is catching up with me as that was way harder than it should have been…But I am pretty proud of that as I was never an elite runner with a lot of wiggle room, so the consistency and getting to the start line and executing is pretty cool.
I will try again this year, but as I say it is getting harder, in the back of my mind I am thinking about 50 sub 3’s, but I need to up the frequency as I only did 2 this year and I probably need to do 4 or 5 a year to stand a chance
bbt67, way way way back I used to play 5 aside at the football pitches near old street in London. and my mate spotted that there was a building with YKK as its name over looking it, no idea if it is still there, but it tickeled us thinking that the lead zip company would be over looking us. Hence the username…
He lives Barcelona so that was the rationale. Might go visit same weekend anyway now I have leave, or he might come over for Northumbrian tri as the next meet up.
Wifes friend is doing the Redcar to Whitby charm bracelet run so I might look at that.
11 days to go, last long run yesterday. Think I’m there in 2:54-2:59 shape for my first non-tri attempt 
Have managed 6 runs >25km, and the last few have gone well with pace intervals. But total volume poor - only 6 weeks > 42km (Inc this week by the end) and not got swim/bike volume to fall back on either so will be very wary of the back 10km biting.
Either way have really enjoyed the training again, and am a lot lot fitter than I was in November so there’s that win.
That would be an impressive off relatively lower volume training, but 30k in 2.12 is spicy. Good luck
That’s 5km home from work Monday morning then a very strong 25km yesterday that felt like I had at least 35km in the tank for, first time I’ve truly believed I’ll hold on.
Friend I’m visiting has done less running then I have, yet asked last week if we should line up with the 2:45 pacer 
then again he’s done a 16:10 5k and 1:17 half this year, but I still suspect he’ll fade towards 2:50-2:55.
I’m not sure I’d count him as a friend after suggesting that
But if boost for the sub 3 hopefuls, LA has cut out a few miles so eve I would be in with a chance:
Cant get a link directly to the Independant article but.
“If you’re having a tough day and want to end your race before 26.2, you can choose to take the turn at Mile 18 and head into the finish line early,” the announcement, posted on a “Race Day Weather” page, said
You get your medal.
Wonder how marathon investigations will cope.
