"Shouldn't I just go out and hammer as hard as I can on the bike, and then try to hold on during the run?" Well, maybe. Especially during a sprint-distance race. And it is a common strategy, especially for strong cyclists. But devising a strategic plan based on your known power output--and sticking to it--can leave you fresher for the run without slowing you much on the bike. Likely giving you a faster overall time.
The best way for this to work is to have a power meter and know your watts at Functional Threshold (basically, how hard can you pedal for an hour). Knowing how many watts you can hold for 5 minutes and 1 minute is helpful during a hilly race.
On a flat sprint-distance course (12-15 miles), you can probably hold 95-100% of your FT power and still have a good run. On an flat Olympic-distance course, it may only be in the 85-95% range. A good idea is to experiment during your training bricks to see how well you run after riding the race distance at various power outputs.
A hilly course is a bit more complicated. If you've been training with hill intervals of various lengths (1 minute to 20 minutes), you can likely hold a higher wattage on the hills, and use the descents to recover. Climbing hard is one of the best ways to shave minutes off your time.
Below is the step-by-step process I used to plan a strategy for the upcoming Wildlfower Triathon (Olympic-distance course). This will be my first time riding it, so I wanted to do some recon.
Plot the Elevation Profile of The Course
There's a good chance the course has already been mapped on mapmyride.com. If not, find the course description and plot it yourself. Be sure to click the "Show Elevation" box. You'll get something like this. Break Down the Course Into Segments
The best way to analyze the course is to break it down by climbs, flats, and descents. Start by listing the mileage and the average gradient of each stretch. If a hill has multiple gradients, it's probably easiest to estimate an average if they're all similar. Here's a spreadsheet I made for the Wildflower course (double click to enlarge in a new window).
The "mile" column can give you a reference when using your odometer on the bike, or simply driving the course before the race. Note that for most of the hills I've averaged the gradients of several sections of the hill to come up with one number.
Determine Average Watts For Each Hill
This step can be time consuming until you get the hang of it. First, become familiar with a power calculator. This calculates the speed you will go given a certain power output, drag coefficient, slope gradient, and the weight of your body and bicycle. I've found these remarkably accurate, especially on steeper climbs where speeds are lower and wind resistance is not so much of a factor (i.e. It's easier to estimate your weight than your drag coefficient. ).
Once you're comfortable with the calculator, start filling in the spreadsheet. Start by noting your FT power (zone 4) and your 5 minute power (zone 5). Mine are 260 and 320, respectively. So for shorter climbs (1 mile or less, or less than an 5 minutes), I'll start by plugging speeds into the calculator that will require a power output in the low zone 5 range. For the first hill, a 5% grade, 13 mph require 290 watts for my bodyweight (155 pounds).
Set up your spreadsheet so the last column is filled in automatically (length/mph x 60) once you enter the mph.
Repeat this step for each hill. For hills longer than 1 mile (or 5 minutes), I've lowered my target watts to a high zone 4. I've opted for the high side of this zone because of the long recoveries after each one.
On the non-steep downhills, I'm estimating 25 mph and 200 watts (an easy tempo pace). The important thing on the downhills is to recover, and I suspect I'll pedal easier than I've estimated. At high speeds it takes a lot of effort to go even 1 mph faster. Once you're over 25 mph on a descent, it's probably best to stop pedaling, get into a tuck and coast. Save your legs for the next climb--it won't cost you more than a few seconds on the descent.
Totaling It All Up
Add up your numbers to see if they make sense. My estimated time is 70 minutes. Looking at the 2008 results, the fastest non-pro bike split was 64 minutes. In earlier races this year my bike speeds have been 85% of the fastest riders. But, relative to others, I climb much better than I ride on the flats. So I'm estimating I'll be at 90% of the fastest rider's speed at Wildflower. So, 64/.90 gives 71 minutes. Right in the ballpark.
Also consider if you're plan is feasible based on your previous training. This plan has me doing seven zone 5 hill repeats totaling 20 minutes, and three zone 4 repeats totaling 24 minutes. Which is very much in the range of my recent training.
Also, this plan should give me a total average watts (not including downhills) of about 260 watts. Considering that is my FT, it may be a little ambitious for an olympic-distance course. While I defintely would not try to hold that output continuously on a flat coure, I'm betting that the coasting and recovery time will allow me a higher wattage.
Postscript
After the race (May 3) I'll give a full analysis of how well the plan went!
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