Is base training making you slower on the bike?

[Sports Science Editor]

It's an interesting debate as to whether aerobic base training is actually necessary or not for all cyclists and triathlon competitors. Primarily it depends upon your specific demands. If you are for example a stage-race rider who will spend multiple long days in the saddle, a large base is something which will undoubtedly stand you in good stead. What though, if you are an amateur triathlete or cyclist, working full time with limited hours for training? What if your races last no longer than a single day and involve only 1-2 hours of riding?

It’s all about power
Training zones are simple tools to help guide your training intensity and as a cyclist you can use either heart rate or power to establish such zones. For the purpose of this article let’s presume that everyone has a power measuring device such as ‘SRM’ or ‘Power Tap’ which displays the amount of power you are producing measured in ‘watts’.

How do zones work?
Simple, the idea behind zones is to ensure that everyone if working at a similar intensity. If every cyclist in a group is working within zone 1, then the intensity should feel the same to each of them, they would all describe the intensity as ‘fairly light’. Generally when cycling clubs ride together the group may ride at the same speed, but riders may be working at varying intensities in order to keep up. To compensate for this they can ride behind another person to gain the effects of slipstreaming, thereby reducing their intensity.

Example zones
Tom visits the lab and completes a maximal ramp test which progressively gets harder until he can’t keep the pedals going, from this test we calculate a ‘maximal aerobic power output’ (MAP) of 350 watts and produce the following 5 zones:

Zone 5 = 90-100% MAP = 315-350 watts
Zone 4 = 80-90% MAP = 280-315 watts
Zone 3 = 70-80% MAP = 245-280 watts
Zone 2 = 60-70% MAP = 210-245 watts
Zone 1 = 50-60% MAP = 175-210 watts

Scenarios to consider
The main thing to identify from the zones calculated above is that the MAP dictates all zones, including zone 1. The higher the MAP the greater the number of watts produced in zone 1 and the faster you will travel at this intensity, although it will still feel like zone 1, it would still feel ‘fairly light’.

Bob’s MAP is 400 watts, his zone 1 therefore calculates as 200-240 watts (50-60%). He finds this ‘fairly light’ but cruises along at 18-19mps, riding a nice road on a nice day. John’s MAP is 300 watts, his zone 1 therefore calculates at 150-180 watts (50-60%). He finds this ‘fairly light’ and cruises at 16-17mph, riding the same road.

Use it or loose it
Your MAP will be at its highest when you are at your strongest (possibly just before your biggest race in the middle of summer). If you ride well below your MAP for long periods of time, you will not maintain your MAP, it wil decrease. This is a simple ‘detraining’ principle, use it or loose it…… let’s go back to the scenario above for John…

John’s MAP is 300 watts and from November to January he only rides in zone 1 to develop his aerobic base (150-180 watts), due to the fact that he only rides at a low intensity his MAP drops to 270 watts. John’s ‘new’ zone is now 135-162 (50-60% of 270), it still feels ‘fairly light’ and his heart rate does not change, to John this feels exactly the same as it did in November, but now he is riding at 15-16mph as opposed to 16-17mph. As a result of his zone 1 riding, John is now slower. Read that again……

Endurance riders beware!
Are you doing Ironman? Riding long sportives? You need to be very wary of thinking that riding long slow miles will always improve performance. In certain cases it is necessary, but for many, it may not be the sole way forward with regards to performance.

I’ve worked with a large number of athletes and I’m confident that 90% of them could comfortably ride 100 miles if I asked them to ride in zone 1. Riding at such intensity is not particularly taxing and the pace would feel ‘fairly light’ for everyone. The key thing which separates each rider is how fast they travel when riding in zone 1, for some it would be 14mph, for others it would be 19mph. This difference in speed is dictated by the number of watts produced within zone 1 and the number of watts produced in zone 1 is dictated by MAP, in fact, the speed at every intensity is controlled by MAP.

If you have been competing in long distance events and found yourself going slower as a consequence, or at least failing to get faster… you need to think about whether you are ‘John’ and whether you need to re-think your approach.


About the author of this training article
Marc Laithwaite, is Sports Science & Coaching Director, at The Endurance Coach. Mark has a Bsc (Hons) sports science and is working towards his Phd sports science. He is a member of the British Association of Sports and Exercise Scientists (BASES), a British Cycling Federation Blood Analyst, BTF Level 3 Coach & Coach Educator, UKA Level 3 Coach and ABCC Level 3 Coach.

The Endurance coach, provides sports science and coaching support services for endurance athletes. Their services include VO2 max testing, lactate profiling and metabolic assessment for endurance athletes of all standards in their own sports testing lab. The Endurance Coach also runs a range of training camps throughout the year and offers physiotherapy and rehabilitation services. For more information or if you are looking for world leading coaches to assist you, e-mail The Endurance Coach.

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