Aerobic Cycling Training

by Arnie Baker, M.D.

Aerobic capacity and aerobic endurance are important cycling fitnesses.

Aerobic Capacity

Aerobic capacity is the ability to work using oxygen in combination with fats and carbohydrates as fuel sources to produce energy.

At low-aerobic levels, fat is the primary fuel source. At high-aerobic levels, glycogen—stored carbohydrate in muscle—predominates as a fuel source.

Aerobic Endurance

Aerobic endurance is the ability of the body to perform aerobic work over long periods. This is important in sustained efforts—in time trialing or in long hill climbing.

To improve aerobic endurance one must improve the quantity or quality of components of this system.

Aerobic endurance involves oxygen transport from the air we breathe to the chemical factories of the body that burn fats and carbohydrates in combination with oxygen for fuel.

This fitness system includes the heart, lungs, circulation, cell transport systems, and the cells’ chemical factories – the energy-producing mitochondria.

Aerobic Training Principles

Aerobic training requires the rhythmic action of large muscle groups, as in cycling or running. Vigorous video game play using only smaller hand muscles can never place enough demands on the body to be aerobic.

Aerobic training begins at about 66% of an individual’s maximum heart rate.

An increasing workload is required to stimulate aerobic training as an individual becomes fitter. Consequently, aerobic training should be progressive:

Since the body is constantly adapting, the intensity of workouts must be increased until an individual’s genetic aerobic potential is reached.

For the very fit, training at rates higher than 93% of maximum heart rate will cause anaerobic systems to kick in, allowing fewer aerobic repeats. For the less fit, anaerobic systems may take over at heart rates as low as 80% of maximum.

Besides reaching your aerobic capacity, you can train to increase the length of time over which you can work at or near this level.

Aerobic fitness may begin to be lost in as little as one to two weeks; training regularity is important. Accumulate thirty minutes of aerobic training twice a week for maintenance.

Intensity, Duration, Frequency

As stated above, aerobic training begins at about 66% of an individual’s maximum heart rate.

To maximally train the aerobic system, riders need high-level aerobic work—loads that result in 80% to 90% of maximum heart rate.

Once you have built a base of a thousand miles or more over a few months, you can aim to train at this intensity two or more times per week. Aim for a cumulative total of about two hours per week.

Endurance may be improved by training at lower intensity levels, but maximal oxygen uptake may not increase.

Spending more time training at high-aerobic levels may be productive during some training phases. During these phases, riders may train at high-aerobic levels up to six hours per week.

There is a limit as to how much time riders can spend at high-aerobic levels because there is a limit to high-aerobic energy sources. Intramuscular glycogen is a limiter.

There is also a neurohormonal limiter. High volumes of high-aerobic work should not be performed routinely because of overtraining risk.

Racers need training at 86% to 92% of maximum heart rate to reach the limits of their aerobic potential. Training near this level overlaps with anaerobic training at times; this is threshold training. When training at such very-high aerobic levels, reduce the overall volume of aerobic work.

Aerobic fitness may begin to be lost in as little as one to two weeks; training regularity is important. Accumulate thirty minutes of aerobic training twice a week for maintenance.

High-level aerobic training is not required for everyone. Riders are commonly able to complete a hilly century successfully without maximizing their aerobic training.

Value of Interval Training

Unless intervals are performed at a cadence, heart rate, power, or torque level above that of continuous work, interval work is unlikely to be of more benefit than continuous work.

One may exercise longer at the limits of high-aerobic metabolism by performing intervals rather than by continuous training. There is evidence that interval training is helpful in high-level aerobic training

Length of the Aerobic Interval

High-level aerobic intervals should be long enough to reach maximum oxygen uptake in most of the intervals, and short enough to minimize fatigue.

Because experimental results are inconclusive regarding the benefits of short (15–30 seconds) and long (up to 5 minutes) intervals for aerobic training, a variety of training intervals is recommended.

My favorite interval length is 3 to 5 minutes. This is because it is relatively easy to perform such intervals effectively.

In order to be effective, the majority of 3- to 5-minute intervals must be performed at workloads above 30-minute time trial pace.

Although not effective in increasing maximum aerobic capacity, intervals performed below 30-minute time trial pace may:

• Help adaptation to high-intensity work
• Build a bigger base/increase overall training volume
• Increase general aerobic or muscular endurance
• Assist in rehabilitation
• Provide variety, reduce boredom
• Provide workout structure, or
• Improve neuromuscular technique or skill.

To train aerobically, intervals shorter than three minutes require similarly short recoveries—otherwise aerobic demands may be low or work may be performed anaerobically.

Mild exercise during rest intervals (heart rate 100–120 bpm) hastens recovery. Keep your legs moving!

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