Know Your Enemy – Part II: Course and Gear Selection

AC_head-1In the last article on getting to “Know Your Enemy” we took a look at how athletes can best make use of the new mapping technology available to all of us via the internet. In that piece I suggested that it’s very much “worth the trouble” to download the elevation data to a spreadsheet so that you can see what sort of grades you’re dealing with over the course of your A race. So you’ve got lots of nice little numbers in front of you right now. The next question is, “what information can be derived from this sort of data?”

Minimal Power/Gear Requirements
First , for the more challenging courses — St. George, Lake Placid, Canada, Lanzarote, France, the big question is: do you have enough plain old power to get up the hills without going anaerobic or ripping your tendons from your bones?

Power vs GradeThe table to the right indicates the sort of power requirements for minimal speed climbing (6mph) up various grades.

For some perspective, some well known course have the following grades:

  • St. George: 52k Climb (x2) @ 1.1% net grade w/2k @ 5.5% and max grade of 16.7%!// 2.9% of the course is at >4%
  • Lanzarote: 23k Climb @ 2.4% w/3K @ 5.6% and max of 12.1% (one of 4 significant climbs) // 5.5% of the course is at >4%
  • Wisconsin: 11 significant hills of 2k+ with max grades of 5-6% // 0.4% of the course is at >4%
  • Lake Placid: 26k Climb (x2) @ 1.1% net grade w/2k @ 4.5% and max grade of 8% // 3.7% of the course is at >4%
  • Canada: 12k Climb @ 2.8% net w/2.5k @ 5.8% and max grade of 8.8% + 23k Climb @ 1.5% // 4.5% of the course is at >4%

When selecting a race course, it’s worth paying attention to:

  • Whether you have the FTP to ride the course. This can be a real concern for courses like St. George which has some double digit sustained sections within the longer climbs with little time to recover and clear lactate thereafter.
  • Whether you have the fitness to handle a lot of climbing in your mod-hard and threshold zones. For most intermediate athletes, completing an ironman at a steady (Zone 2) intensity is challenging enough. Throwing in a lot of forced mod-hard or threshold climbing is likely to put a lot of folks square in Bonkville. For most athletes, I would recommend no more than a third of your race duration (approximately 10-15% of race distance) should be mod-hard climbing (at an IF of ~0.85). Additionally, I would recommend that no more than 10% of your race duration or about 3-5% of your race distance be at threshold. Even with an equal distance of coasting on the descents and the balance as easy-steady riding (at an IF of 0.65) it will be tough to keep bike TSS <285 for a six hour bike split if either of these are exceeded. Worth considering.

So, putting these recommendations in the context of the realities of the race courses mentioned above, what are the implications?

  • Most challenging courses involve sustained climbs of at least 5-6%. These will require FTPs of about 2.5w/kg to survive the most moderate of these climbs. Realistically, with pitches of 8-12% and sometimes 16%, without opportunity for subsequent recovery, FTP needs to be in the realm of 3.5w/kg to merely avoid “the walk of shame” on many of these.
  • Most challenging courses are made up of at least 3-6% of climbing with significant grades of 4-6%. In my opinion, most of this climbing needs to be done in the mod-hard zone in order to keep TSS moderate and give the athlete a good shot at having enough energy to run a marathon off the bike. I would suggest we want a mod-hard power of at least 2.5w/kg in order to cover these extended 4-6% grades without delving too deep into our energy stores.

Gearing_v_gradeOther than picking a course more in line with your capabilities, there is little that you can do on this front after you “signed the dotted line.” This isn’t true of another key consideration — gear selection. You can significantly change the torque demands on your legs by simply opting for a smarter gear selection for the course in question. The table to left includes some suggestions for different goal climbing powers for different max grades at a minimal cadence of 60rpm.

Considering the bulk of tough courses have periods of 8-12%, an athlete with the recommended minimal FTP of 3.5w/kg will, at the very least want a 34/28 compact gear ratio in order to keep cadence at >60rpm on a 10% grade at 6mph.

In my opinion, it’s not until the athlete hits an FTP of 4w/kg that “regular gearing” becomes even worthy of consideration. Even then, a 50/34 at 90rpm will get an athlete to 34mph. The question needs to be asked, should the athlete even need to pedal at speeds faster than this?

This article has been about the minimal standards required to “survive” the toughest of the ironman courses. In the next and final piece in this Know Your Enemy series, I’ll take a look at how to best distribute your energy on different courses to yield the fastest overall time for those athletes with a little extra energy to burn.

Until then…

Train smart.

Categories: Racing

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Alan Couzens

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