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Joe Friel's take on coasting - recommend this to your competitors

This may have already been posted, but search does not seem to be working too well right now and I didn't see it in this forum yet. Anyway, check out this almost humorously absurd advice on hill climbing and coasting from Joe Friel's blog:

 

A triathlete asked me some time ago what he should do on downhill portions of a bike course. Should he pedal hard, pedal easy or coast? That was a great question and one that also applies to cyclists doing time trials. It does not apply to runners as their speed is not significant enough to cause substantial drag.  

 

On a bike as your speed increases linearly (a straight line from, let’s say, 20 to 25 mph), the power required to go faster increases exponentially. This largely is because of drag. The energy required to overcome air resistance (drag) is a function of land speed to the third power. So while it is only a 25% increase in speed to go from 20 to 25 mph, there is something like a 75% increase in the energy required to achieve that additional 5 mph.  

Why am I telling you this? Because as you go down hill and your speed increases if you want to go even faster than coasting allows the energy “expense” of the additional miles per hour is going to cost you dearly.  

The bottom line is an old adage which says that if you are riding on a fast portion of a course (down hill) ride easy; but if you are riding on a slow portion of a course (up hill) ride hard. So when riding fast on a downhill don’t expend as much energy as when riding uphill. The longer the event, the more important this is. For a sprint-distance triathlon or a short time trial you can go much harder downhill than if it was an Ironman or a long TT.

The best advice I've seen for this came from Alan Couzens, an exercise physiologist and triathlon coach. He tried to nail it down for Ironman triathletes with his “50-40-30-20-10 rule.” It goes like this (reprinted with permission of author)….   

Coast at >50km/h

Pedal easy at >40km/h

Pedal steady at >30km/h

Pedal moderately hard at >20km/h

Pedal hard at >10km/h

You can read Alan's blog on this topic for an in-depth discussion of how he came up with his rule by going here. 

Alan’s Ironman rule may not work for your race distance, but the concept remains the same: Conserve energy when the bike is going fast; expend energy when the bike is going slow. How much energy depends on how fast the bike is going, how long your race is and how fit you are. The less fit you are the more you will need to conserve energy on down hills. Based on this concept you can come up with your own rule for each race distance you do.

So the answer to the athlete’s question in the first paragraph starts with (you guessed it) “it depends.” It depends on speed, race duration and fitness.


 

http://www.joefrielsblog.com/2010/0...nhill.html

I used to think that 95% of the people I saw racing Ironman Wisconsin this year had no idea what they were doing, but now I realize that they were actually race execution Ninjas thoroughly versed in the Couzens/Friel school of riding.

Comments

  • I used to think that 95% of the people I saw racing Ironman Wisconsin this year had no idea what they were doing, but now I realize that they were actually race execution Ninjas thoroughly versed in the Couzens/Friel school of riding.

    I love it when they put this stuff out, Friel's blog post about optimal bike TSS was another classic
  • It's part of RnP's program of MIS-information. Keeps us all in the EN haus much smarter, execution-wise. Like the title said, sell your competitors on this!
  • Whoa - it doesn't even make sense from an intuitive stand point. Everyone agrees that the fastest way to run is an even paced race, and sometimes a negative split in the second half. But Friel/Couzans are arguing that the hillier the course the more you should approach it like it were an interval work-out instead of constant pacing = constant power.
  • I like to bash the Friel posse as much as the next guy. Just want to point out that when really smart doodes like Chris Whyte and others model this sort of thing, the basic conclusion is that it is net faster to go a little harder uphill and a little easier downhill. Very valuable for people pacing a 40k TT effort and such. And the EN pacing 'gears' use a variation of this theme. The guidance to coast at 50km/h is quite similar to Rich's.

    All that being said, the way it is written is clearly going to get most people doing the wrong things. But it's not based on horribly misinformed fundamentals.
  • Mike I agree with you, but you hit on a very big caveat: "when really smart doodes" read that they likely draw drastically different conclusions than your average AG triathlete or perhaps even more than Friel himself intended. The coasting guidance by Couzens as you noted is not bad, coast over 30mph and pedal easier as you approach that point. The guidance is somewhat redudant, save for say someone grinding a 54/55T in a TT, your gearing will limit your power downhill as you likely spin out and coast whether you want to or not.



    The fatal flaw is the attempt to dumb it down to meaningless terms of pedal "moderately" or pedal "hard". Without providing finer granularity of what constitutes "hard" by either Friel and/or in the extract from Couzens you are relying entirely on the perception easy, moderate hard to the reader. As we've all likely seen from experience, most athletes at an IM seem to have these pegged at something along the lines of 120-200% FTP on climbs and quickly gravitates from about 30% to 0% on downhills as the fatigue from repeated Z5 "hard" efforts quickly sets in.



    Friel's attempt to boil it down to the 'old addage' line is what at least makes it at the very least appear like he is completely missing the point. You point that out as well, so essentially yes, I agree with you.



     

  •  That post is like a lot of the others in that it really does not say anything useful to anyone.  i do not think the concepts are really out of line with the EN bike pacing guidance. The power gears allow for the highest wattage is permitted when climbing short hills which is also when you would be going the slowest, right?  However, things like ride hard, harder , hardest ...what the hell does that mean?  Gee thanks coach...

  • Beverly, take a look at the race execution resources around here. The race gears for proper execution are

    1st - goal watts -5%, 1st hour of the day and downhills (until you reach about 34mph, then coast)
    2nd - goal watts, flats and shallow rollers
    3rd - goal watts +5%, long hills, greater than 3 minutes
    4th - goal watts +10%, short hills, 1-3 minutes

    So RnP give the very same advice you're suggesting 'fails the sniff test'. This program has worked for thousands of folks over many years. I fail to see where it fails the sniff test.
  • What ChrisG said:

    • Yes, you should ride a little harder on hills.
    • Yes, you should maintain your effort on the downhills until you reach speed X, then just coast. Our guidance is that X = about 32mph, as your airspeed is so high that additional speed comes at the cost of huge watts and you can go the same speed, or maybe faster, by just getting very aero and coasting.

    The rub of course, as Chris says, is that if you'd define harder, a little harder, etc, people read that as HARD. I can bet that many people out there will be hammering the hills because Joe sez I can go harder.

    Inside EN, we have very well defined guidance for exactly how hard, or easy, you should be going at all times.

  •  That post is like a lot of the others in that it really does not say anything useful to anyone.  i do not think the concepts are really out of line with the EN bike pacing guidance. The power gears allow for the highest wattage is permitted when climbing short hills which is also when you would be going the slowest, right?  However, things like ride hard, harder , hardest ...what the hell does that mean?  Gee thanks coach...

    Totally agree, it took me 7 years of triathlons to figure out how to execute on hills. Probably why I raced IMFL 3x. The soles of the feet thing never clicked w/ me either.
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