The previous articles in this series have been concerned with the initial adaptation phase of PowerCranks use and the subsequent Basic Endurance phase of training.

It is now time to get serious and discuss the strategy involved to promote a successful PowerCranks racing experience.

 
Cadence

The first issue to be addressed here is cadence. What cadence is most appropriate for racing on PowerCranks and what factors determine this cadence.

Power output is the single most important factor in determining an appropriate PowerCranks racing cadence. What will be the power output sustainable for the duration of your race? This will, of course, depend on the race distance - as race distance increases, the sustainable power output will decrease.

There exists a mechanical relationship between power output, cadence and torque (or force). As power output increases, cadence must also increase if the torque required to produce the power output is to remain the same. In other words, if torque is to be minimised, then cadence must increase as power output increases.

To cut a long story short, if you are producing 300 watts of sustainable power then the most appropriate cadence to use is somewhere around the 85 rpm mark. This value was determined by studies investigating conventional cranks and, due to the increase in efficiency that PowerCranks provide, I am taking an educated guess in stating that the most efficient PowerCranks cadence for 300 watts will be slightly lower.

If sustainable race power output is higher, then the most appropriate cadence is likely to be higher and vice versa.

Theoretically, 85rpm represents an optimisation of neuromuscular efficiency at 300 watts.

Neuromuscular efficiency is related to muscle recruitment and force application and it is said to be maximal when the force/muscle activation to produce a particular power output is minimised.

Energetic efficiency is different again and it relates to oxygen consumption while exercising at a certain power output. The cadence that produces the lowest oxygen consumption for a given power output is said to be the most energetically efficient cadence, and, for sub maximal power outputs, it is lower than the most neuromuscular efficient cadence.

Why is it lower? I am having an educated guess here in stating that it likely has something to do with the energy cost of moving the limbs. It takes energy just to move the legs up and down without producing any power and higher movement frequencies, ie cadences, have a higher energy demand.

Studies have shown that preferred cadence of cyclists while producing the same power output decreases from the most neuromuscular efficient cadence to approach that of the most energetically efficient cadence after a sustained period of cycling at sub maximal intensity. Scientists have theorised that this is caused by a change in the recruitment pattern of the muscles involved -  as the muscle fatigues, the fast twitch/high force fibres are called on to make a greater contribution to power generation.

This is the reason low cadence “strength endurance” work has become an accepted part of a cyclists preparation. During this work, the fast twitch fibres can be trained in an endurance fashion at specific race pace power outputs.

This is the training that is critical for a successful PowerCranks racing experience, especially over the longer race distances.

 

With the pertinent theoretical aspects covered, it is time to get practical and investigate the strategy involved in preparing to race on PowerCranks.

 
Intensity

Firstly, it must be determined what intensity of effort will be employed in the target race. If it is a sprint distance race, for example, intensity above that of individual maximal lactate steady state will be the intensity most important to target in training. At the other end of the extreme, if the race is an Ironman, intensity in the vicinity of Lactate Threshold (Fatmax Intensity) will be more appropriate.

One of the very best ways to determine an appropriate target racing intensity is to derive one from previous racing benchmarks. The previous benchmark time can be converted to average power output sustained for the distance. This value will determine the appropriate intensity of training that will be required in order to achieve a new benchmark performance.

For example, if the most recent best time over a flat – undulating 180k time trial is 4.5 hours, this translates to an average velocity of 40 km per hour. Utilising one of the power output calculators on the internet, a corresponding average power output can be determined. In this case for a 65 kg athlete riding an 8 kg bike, 40 kph is equivalent to approximately 260 watts.

An appropriate intensity to target in training for this athlete would be around 270 – 280 watts.   

This work can be considered the specific endurance component of training, and it is the volume of this work that will increase in the build up to the race. The length of this build will vary depending on the distance of the race.

As was stated earlier, it is critical to perform some of this specific endurance work at lower cadences in order to target and train the fast twitch fibres in an endurance fashion. A 50/50 mix of race cadence and low cadence (60 – 65 rpm) is a sensible proportion to target.

At the height of the build period, weekly volume of specific endurance work should approach the volume required in the target race, and, even better, this volume should be achieved in one session for all distances with the exception of the Ironman. A realistic target is approximately 120k/3 hours of Ironman specific power output in a single session.

This training can be completed as a mix of hill repetitions, flat repetitions, and stationary trainer repetitions depending on the terrain over which you will be racing. For example, if the course is going to be flat, some of these intervals should be done on the flat. Perform longer intervals for lower power outputs and vice versa.

The vast majority of this work should be done while on the aerobars.

Leading into the race, the specific endurance work should mimic the exact demands of the race - specific race pace time trials at race cadence should be targeted. Strength endurance should be maintained in this period with a small volume of low cadence work during easy rides.

Additionally, it would be sensible to do some race pace runs off the bike at this time. Doing some racing at distances/power outputs similar to that of the target race would be ideal.

 
Strength, Skill and Basic Endurance should be maintained in this build period.

 
Strength

For those younger athletes the strength endurance work should be enough. Older athletes or inexperienced athletes would probably benefit from one strength session per week targeting the muscles involved in the cycling action in a specific fashion.

Under this banner comes gluteal function. It is critical to maintain gluteal function. The gluteals must be activated throughout the stance phase of the running action. Very common in triathletes who typically spend a lot of time in the time trial position, is tight hip flexors, tight adductors and tight ITB’s. Tight hip flexors and adductors inhibit the hip extensors and abductors ie glutes and this can cause all sorts of problems.

The remedy here is to stretch the hip flexors, adductors and ITB’s regularly and do exercises that train the gluteals specific to the demands of running biomechanics.

 
Skill

Maintain the one legged pedalling drills during easy rides, especially while down in the aerodynamic position.

 
Basic Endurance

This is not so important if training for the Ironman, as the specific Ironman pace work will maintain basic endurance on its own. For shorter race distances, a 3 hour plus mixed terrain ride every fortnight should be sufficient to maintain basic endurance.

 

Bike Set Up

I have had most success utilising a steep effective seat angle, somewhere in the vicinity of 78 degrees. I have found that this enables me to effectively recruit the upstroke musculature while being able to adopt a relatively aerodynamic posture.

At the same time, as Frank Day will tell you, it is all about power output and efficiency. Aerodynamics are crucial if you are time trialling at 50 kph, but at the average triathletes velocities, especially over the longer time trials, there is a greater relative advantage in the efficiency gained from Powercranks use, than the aerodynamic advantage gained from 3 inches of aerobar pad drop.

Experiment a bit with this. A higher aerobar pad position will be necessary to start with but can be lowered progressively as the body adapts. At the same time don’t be too concerned if you can’t get your nose on the front tyre.

 
Summary

In summary, for a successful PowerCranks racing experience:

•   Develop a high level of basic endurance, skill and strength in the base period.
• Determine a realistic sustainable power output target.
• Build the volume of work completed at the sustainable power output target.
• Perform some of the above work at lower cadences to develop strength endurance.
• Maintain Strength, Skill and Basic Endurance in the build period.
• Perform some specific race pace time trials in the weeks leading up to the race.
• Maintain hip flexor/adductor/ITB flexibility and gluteal function throughout the preparation period.
• Set up bike with a steep effective seat angle.

 
Follow these guidelines and you won’t regret your decision.

Good luck with it.

Take care

Courtney