In the first article, I described how to train for a one-day event: the general principles and the training phases. What if you want to set a PR? Let's look at how to train for a fast double.

Energy Systems
When we do a long ride, we use three different energy systems and we have to train each energy system differently. The systems are:

• Fat-burning: at low to moderate intensities, we burn primarily stored body fat for fuel. Our endurance depends on how much body fat we have (usually not a problem!), our supply of the enzymes necessary to metabolize the fat, and our supply of mitochondria - where the enzymes metabolize the fat - within our muscles. We develop enzymes and mitochondria through long, slower rides.


• Glycogen-burning: at a moderate, conversational pace, we're riding aerobically and metabolizing both body fat and glycogen from stores in our muscles and liver. A well-conditioned rider can store roughly 400 - 500 grams (1,600 to 2,000 calories) of glycogen. His or her endurance is limited by this store of fuel as well as the supply of the specific enzymes necessary to metabolize glycogen aerobically. The supply of enzymes can be increased through aerobic training and, of course, the store of glycogen can be replenished by consuming carbohydrates while riding.


• Anaerobic glycogen-burning: at high intensities, when we are breathing hard, we aren't taking in enough oxygen to metabolize fat and glycogen aerobically. The fat-burning metabolism shuts down and we shift to anaerobic metabolism of glycogen. This produces lactic acid as a by-product - we all know that lactic burn in our legs.

We use a different mix of the energy systems depending on the length of the event and the pace at which we ride the event:

• During high-intensity road-races and time-trials we use a mix of aerobic and anaerobic metabolism of glycogen.


• During fast doubles we use primarily aerobic metabolism of glycogen supplemented with metabolism of stored body fat.


• During slower tours we rely primarily on metabolism of body fat, supplemented with aerobic metabolism of glycogen on the climbs and when riding fast.

Riding a Fast Double
To ride a fast double, you need to:

1. Maximize the amount of time you spend riding in your threshold aerobic zone - the zone before you go anaerobic. Be careful not to go anaerobic - you'll have to recover and that will slow you down - and don't drop into the easy aerobic pace where you're burning body fat. You need to learn to ride in a fairly narrow zone of intensity. (Because you're primarily burning glycogen, you also need to eat a lot of carbohydrates during the event.)


2. maximize the amount of sustainable power you can produce without going anaerobic.

You can train to maximize both the time you spend in the threshold zone and your power output in that zone. How? By specific training based on your anaerobic threshold.

Your anaerobic threshold (AT) is the point at which your body switches from a primarily aerobic metabolism to a primarily anaerobic metabolism. You start to breath hard and your legs burn. You can estimate your AT by riding a time trial (either flat or a hill climb) that takes about 30 minutes to complete. Wear your pulse monitor, ride absolutely as hard as you can, and note your average pulse. Your average pulse for the time trial will be very close to your AT. (If you test yourself in a competitive time trial, rather than one in training, your average pulse will be about 5% above your AT.)

Now that you know your AT, you can pay attention to which energy systems you are using during rides and, thus, to which energy system you are training:

• Fat burning: heart rate less than 75% of your AT. Recovery rides and the easy portion of longer rides.


• Aerobic: heart rate between 75 and 90% of your AT. To ride a fast one-day event, you should keep your pulse in this zone, maximizing the amount of time in the upper part of the zone.


• Anaerobic: heart rate more than 95% of your AT.


• If your HR is 90 - 95% of your AT, you are starting to go anaerobic and starting to shut down the aerobic metabolism, but not riding hard enough to get the benefits of anaerobic training. Learn to slow down or speed up, depending on your training goals for that ride.

Even if you plan to ride primarily in the aerobic zone, you need to train in all three zones. Training in your fat-burning zone will increase the mitochondria and the blood supply to your muscles. Training anaerobically will increase your oxygen uptake and raise your anaerobic threshold so that you can go faster without going anaerobic.

Progressive Speed Workouts
To develop sustainable power and speed for a one-day event, you can do three different types of workouts. All of these workouts are stressful. The majority of your riding time each week should be in endurance rides and recovery rides in the lower aerobic and fat-burning zones. After you have built a good base of early season miles, mix in two days a week of:

Threshold workouts at 85-90% of your AT. These workouts will increase your muscle endurance, your ability to sustain a high pace for hours. Early in the season, start with two or three cruise intervals of 10 to 20 minutes in this zone, with full recovery between each interval. Gradually increase the number and duration of the intervals. Later in the season, go for tempo rides of two to three hours in this zone, building up to a century or more at this pace.

More Information    UltraCycling Magazine Authoritative information for endurance cyclists. Each issue contains articles by experts on: training nutrition equipment event preparation rider profiles race results Join the UMCA and receive six issues a year.

Order back issues

Sub-anaerobic workouts at 95-100% of your AT. These workouts will increase your AT, i.e., allow you to go faster without going anaerobic. If you could sustain 150 bpm for 30 minutes, after several months of this training, your AT could increase to 155 or 160 bpm. After at least a month of threshold workouts (85-90% of AT), you are ready to do extensive intervals. Begin with two intervals of 8 to 10 minutes at 95 - 100% of your AT, with full recovery in between each interval. Gradually increase the duration and number of the intervals. Time trials are another excellent type of sub-AT training.

Super-anaerobic workouts at more than 100% of your AT. After several months of sub-AT training, you'll stop improving. The extensive intervals won't overload your body. Move on to more pain: intensive intervals at 100 - 105% of your AT. These intervals are shorter, 3 to 5 minutes are typical, and are done in sets of three or more without full recovery between intervals. Generally, the recovery period is half the work interval, e.g., 4 minutes hard with 2 minutes recovery.

These workouts help you prepare for that fast double in two ways. The threshold workouts increase your specific muscle endurance, the power that you can sustain for hours. The sub- and super-anaerobic workouts increase your anaerobic threshold, so that you can produce more power without going anaerobic. If you are training for a specific event, you should do these workouts in similar conditions and terrain to that event.

Your training should culminate with race pace training. If you plan to ride a 12 hour double century, then practice riding 6 hour centuries. Learn what that pace feels like and learn to sustain it, not going slower or faster.

When you go for the PR, discipline yourself. If you go anaerobic on the first big climb, you'll have to slow down later to recover. Try to stay below 90% of your AT as much as possible . . . but not much below there!

Related articles