Latest Article For Triathlete Magazine – August 2008

Build off-road power

Take a few tips from XTERRA’s top girl and get ready to suffer

By Melanie McQuaid

Aug. 29, 2008 — Racing a mountain bike is all about power. XTERRA racing requires big fat watts produced in short bursts, followed by lung-burning, uncomfortably long periods of grinding out the watts in between. Periodically there will be respite found in sections where the power output is interrupted by technical challenges, which gives your legs a chance to grasp at recovery while you focus on navigating the trails safely. It hurts quite a bit to race a mountain bike well because going fast off road is all about finding the fastest route from point A to point B and hoping that there will be enough left at the end to finish. Ideally, the finish line and your last reserves meet perfectly.

The lack of consistency is the biggest challenge of mountain biking and is likely the biggest reason why racing XTERRA versus a road triathlon stymies even the most accomplished of triathletes. While time-trialing on the road is very difficult, the snap required to accelerate over difficult obstacles, or maintain momentum through rolling off-road terrain, demands very specific training for success. The key to success is developing the ability to produce a large amount of power over a very short period of time over and over again without full recovery. If you analyzed my PowerTap graph from a mountain bike race or XTERRA, you would see that there are large spikes in power generation without any significant periods of recovery, except in the case where the trail points downhill.

On the road the key is to maintain the highest consistent power generation you can without ever going into the red zone. Understandably, the red zone is home to the XTERRA racer, which explains why running off the bike in an XTERRA event is such a terrible ordeal. There never can be any conservation on the bike if you want to put yourself in a position to do well in the race. Running after this kind of effort on the bike is also required in training, but we will save that for another article.

By Rich Cruse
McQuaid_By_Rich_Cruse
I believe the ability to ride this way requires a multi-pronged approach. First, a solid base of riding is necessary to be able to recover from maximum efforts that are done with incomplete recovery. In short, a lot of miles on a bike, and ideally a lot of miles on a mountain bike, are necessary preparation for the quality work. In addition to low-end aerobic base work, miles on your mountain bike also provide an opportunity to work on your efficiency off road. Riding in trails with solid skills allows you to make the most of your fitness. Without good skills, all your speed can go to waste by over-pulling the brake levers. So, ensuring that enough time goes into skills as well as fitness is very important.

Once you have a solid base you can then focus on your maximum aerobic power and your maximum aerobic capacity. Initially, I work on these two things independently. As the season progresses I use races to train both energy systems together and include short, specific workouts that incorporate maximal power and aerobic capacity intervals together.

For instance, a workout to help develop maximum aerobic capacity would include one-minute hill repeats. This is not a true maximum power effort, because you can only sustain your maximal effort for less than 30 seconds (which would essentially be a sprint). In this interval, you are working on the maximum effort you can sustain over one minute. Thus, this remains aerobic work. Depending on your level of fitness, doing 5-10 repeats of one minute with two minutes of rest in between would be a good start.

You can do this interval on-or off-road. On the road you want to have a fairly large gear, but not so large that you get bogged down part way through the interval. If you are doing it on your mountain bike, you want to find a non-technical trail or dirt road to do this workout. One-hundred percent aerobic capacity efforts like this will build power and strength and also help you determine what 100 percent feels like. Too much aerobic training can leave you out of touch with what your maximum effort really is. Knowing where your limits are can help you get the most out of yourself on race day. However, this workout is quite damaging to tissues and the nervous system, so 48 hours is advised for recovery from this workout.

To next workout works on a similar energy system but approaches it in a different way. To help build aerobic power, versus aerobic capacity, repeats of 3-8 minutes with shorter rest of 1-4 minutes will help develop high-end aerobic fitness. Starting with 3-6 repeats of about 4 minutes, try to keep the effort consistent on each interval. Using a load-generating trainer can help with this. I set my power levels according to test results that indicate what wattage corresponds to each lactate response. You can set your levels by perceived effort as well. This set should be done at about an 8 our of 10, meaning really hard/race pace. By doing these repeats at 80-85% of your maximum power, you will find that by the fourth or fifth repeat you will be producing more lactic acid than you have cleared from the last interval. Although the effort is comfortable to start, all the work is above your lactate threshold and the cumulative fatigue forces your body to adapt to riding with lactic acid in your system. The last repeat should be very difficult but not impossible to complete. This workout should only take 24 hours to recover from.

A mountain bike race or the bike portion of a XTERRA will require fitness acquired from each of these workouts, but will demand that you use them in conjunction with one another. For instance; after accelerating up a steep rise you will continue to pedal through a rocky section steadily before accelerating one more time over another rolling hill and then descending through some single track. This could look like one minute at maximum power; followed by four minutes at threshold power; followed by one more maximal effort and two minutes of recovery.

In season, I prepare for this kind of racing by doing intervals of three minutes with one-minute recovery. The first minute I do just below my maximum aerobic power; followed by another minute at 90 percent; one more minute at 85 percent; one minute. It may seem like I am “slowly dying” in these intervals, but really I am trying to do mostly high-quality aerobic training while making sure there is a large quantity of lactic acid in my system by blasting my legs in the first minute. The second minute is a balance point where I can almost recover and clear some of the lactic acid—so it trains my body to flush lactic acid out of my system while still working hard. The third minute I basically hold the pace and continue to flush lactic acid (at least in the initial repetitions). As I do repeats of this set, the initial minute gets more and more difficult and the second minute becomes less and less comfortable.

Often momentum makes the biggest difference while riding off road. By maintaining your ability to find your maximum power, you can conserve your momentum and ultimately your speed. That makes the difference between good bike riders and great mountain bike riders. The best riders are very powerful and can tolerate lots of lactic acid in their legs for sustained periods of time. For your next XTERRA, find your maximum aerobic capacity and build on your maximum power. It will pay dividends on race day.

Based in Victoria, Canada, Melanie McQuaid is a three-time XTERRA world champion. For more information about McQuaid, please visit www.melrad.com

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