Training with Power Meters E-Book

Louis Passfield

• Herausgeber: Crowood
• Kategorie: Lebensstil
• Sprache: Englisch

Seitenzahl: 277

Veröffentlichungsjahr: 2015

Beschreibung

The last quarter of a century has seen major developments in the world of cycling. Heart-rate monitors, GPS and smartphone apps are all used by riders of all abilities up and down the country as part of their training programme, but it is the power meter that really stands out as the ultimate tool for any cyclist who wishes to train to their full potential. Power has become the common currency of training discussions amongst the growing number of cyclists who have splashed out on a power meter. But does the average cyclist fully understand the figures displayed on their bike computer screens and, even if they do, can they use that information in the most effective way? Professor Louis Passfield was the first scientist in the UK to work and study with power meters. In this book Professor Passfield shares some of his vast experience and shows that you don't have to be a pro cyclist, triathlete, or coach to reap the benefits of training with a power meter.Fully illustrated with 50 colour images and diagrams.

Leseprobe

TRAINING WITH POWER METERS

LOUIS PASSFIELD

FOREWORD BY ROB HAYLES

First published in 2015 byThe Crowood Press LtdRamsbury, MarlboroughWiltshire SN8 2HR

www.crowood.com

This e-book published 2015

© Louis Passfield 2015

All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information storage and retrieval system, without permission in writing from the publishers.

British Library Cataloguing-in-Publication DataA catalogue record for this book is available from the British Library.

ISBN 978 1 84797 898 1

Frontispiece: Radu Razvan/Shutterstock.com

CONTENTS

Foreword by Rob Hayles

Preface

Introduction

CHAPTER 1   AN OVERVIEW OF TRAINING WITH POWER METERS

CHAPTER 2   THE POWER METER

CHAPTER 3   PLANNING TRAINING WITH POWER METERS

CHAPTER 4   PRINCIPLES OF TRAINING WITH POWER METERS

CHAPTER 5   TRAINING INTENSITY BANDS (TIBs)

CHAPTER 6   AEROBIC AND ENDURANCE FITNESS

CHAPTER 7   ESTABLISHING YOUR TRAINING INTENSITY BANDS

CHAPTER 8   TRAINING WITH YOUR POWER METER

CHAPTER 9   TRAINING WITH POWER METERS TO IMPROVE PERFORMANCE

CHAPTER 10 MONITORING YOUR TRAINING

CHAPTER 11 FURTHER THOUGHTS ON TRAINING WITH POWER METERS

Appendix 1: Example Workouts

Appendix 2: Example Training Blocks

Index

FOREWORD BY ROB HAYLES

Science in cycling has been there from the start of my career. Initially it was quite basic, before first advancing to using heart rate monitors in training and then, a little later on, to power-measuring cranks. Thanks to Louis, I was the first rider in the UK to use the German SRM power meter in a race. During the race, riders were coming up to me and joking, ‘What’s on ITV?’ or ‘Can you get Eurosport on that?’ But in recent years power meters have come on in leaps and bounds. With modern power meters and help from guys like Louis and the other team physiologists, I was able to implement my training much better than was previously the case.

In recent years, especially within the last decade, other previously strong cycling nations, Italy and Germany for instance, which led the way, are now looking at Britain and seeing what we do. From a British point of view cycling has turned itself on its head. One of the major factors in British Cycling’s success has been its strong coaching and scientific input and the use of power meters has been central to this. Louis was the first person I knew to start working with a power meter. In this book he uses this scientific and coaching experience to explain clearly and simply how to get the best out of yourself by training with a power meter.

Rob Hayles is a successful former professional cyclist who now presents regularly on television. On the track, Rob won two World titles and three Olympic medals. He was a member of the British Cycling team for more than sixteen years with team mates Sir Bradley Wiggins and Mark Cavendish.

Rob Hayles competing in the Tour of Britain.

PREFACE

When I was younger I wanted to win the Tour de France. It was the reason I studied sports science at university and learnt about the science of training. I tried to apply this knowledge to my own bike training and became a successful cyclist.

Shortly after graduating I made it to an Olympic training camp. At dinner I sat at the same table as Sir Steve Redgrave. Even before the 1992 Olympics, with many years still to row before his fifth gold medal, he was already a sporting legend. I was there with other dedicated athletes preparing for the 1992 Barcelona Olympics. It was a heady experience. To get there I had spent a decade dedicated to bike training and extending myself further with academic study. This was why on the last day of the camp I was sat in the team car alongside the national coach, reflecting on how things had worked out for me. I was watching several members of the Great Britain team dominate a road race. The only thing was that these were younger, junior raw talents powering away on their bikes. And with all my physical and academic training I realized that I could perform better as a scientist than as a cyclist.

2014 Tour winner Vincenzo Nibali, during Stage 14, Col du Lautaret. (Radu Razvan/Shutterstock.com)

A quarter of a century later I continue to study and research training. I have witnessed first hand exciting developments in cycling and training. I can even claim to have added a little to what is understood about the science of training. And along the way I have had the privilege of working with some of the best riders and coaches in the world.

This book is about sharing some of the benefits of this experience. You do not have to be a serious competitive cyclist, triathlete or coach to read this book. You just have to be interested in improving fitness and be motivated to find ways of doing it more effectively, especially on a bike and by training with a power meter. I hope you find it useful.

INTRODUCTION

In July 1992 Chris Boardman won Great Britain’s first track cycling gold medal for seventy-two years on the Barcelona Olympic velodrome. As he raced, I became clearer on what is required to reach the top step of the podium in one of the world’s major cycling events. I was then British Cycling’s sports scientist, working with Peter Keen, Boardman’s mentor. I had returned to the UK from our Olympic training camp in Majorca just in time to watch the race on television. At home in Sussex, the BBC coverage allowed me to watch Boardman fly around the track on his black Lotus bike to catch his tall German rival, Jens Lehman. Having been the scientist for the Barcelona Olympic team I knew better than most what it had taken for Chris to succeed in his gold medal quest. In my flat, mounted on my own bike was an SRM power meter, probably the first to be seen in the UK. How I wished that we’d been able to install it on that Lotus before the Barcelona Olympic Games began. From laboratory testing we knew that Chris was in the form of his life. But we could still only guess at how he had performed during the race itself to set a new World and Olympic record.

Any data on elite athletes was extremely scarce in those days, and there were virtually no measurements available from actual competition. This was why I had been working on a special project earlier in the year, before the Olympic Games started. My aim was to better understand the demands of road racing and how hard the riders had to work during a stage race in particular. A heart rate monitor without wires that could record data was still quite novel in 1992. Polar had produced one and were keen for me to use it with the British team riding the Milk Race (a forerunner of the Tour of Britain). Using the Polar Sports Tester I was able to conduct ground-breaking research by recording the riders’ heart rate each day of the stage race. From the riders’ heart rate I could calculate their power output in order to estimate how hard they had worked. The problem with this approach is that your heart rate is not only affected by how hard you have worked. Lots of other factors – like excitement, tiredness, hydration and temperature – can affect your heart rate too. Of course these factors are part and parcel of stage racing. My calculations could therefore only ever be considered a crude approximation, no matter how cutting-edge the Polar heart rate monitor.

It was not until the following year (1993, the year after Boardman’s Olympic success) that I was able to measure more precisely what it takes to be an elite road racer. I managed to persuade a promising local young rider to endure a battery of laboratory fitness tests and to let me fit a power meter to his bike. The national coach and I then followed the race anxiously in the GB cycling team car, hoping the young rider could last the pace. This is how Rob Hayles, later to become a double world champion, became the first to ride a premier UK road race with a power meter (much to the amusement of his rivals at the time, it has to be said). Later that year on the velodrome in Bordeaux, just as Miguel Indurain led the Tour de France into town, Boardman broke Graeme Obree’s world hour record. This time Chris and his mentor Peter Keen had been able to use the power meter as part of the event preparation, and so for the first time we were able to measure exactly how hard you have to ride to break a world record.

Having looked at where my understanding and use of the power meter originated, let me now speed into the future to consider how your power meter will evolve. The power meters of the future will rely on built-in sensors so that you remain unaware of their presence until you switch on your data receiver. Innovative companies such as Stages have already started to make their power meters on this basis. Unlike the present, your power meter sensors will be located so that you will be able to measure how hard you are riding even after you have swapped your wheels or even changed your whole bike. Indeed, it’s likely that all the contact points between you and your bike, and your bike and the road, will be instrumented: saddle, handlebars, left and right arms and legs, and front and back tyres. These developments are largely hardware based and much of the necessary technology is already available. Instrumenting your bike in this way and gathering the resulting data is therefore feasible, at least in theory, with sufficient resources and the right ‘know how’. But while the hardware advances will enable you to measure more, the really exciting advances lie in the information to be extracted from these measurements and how it will help you.

Unlike the present, the power meter of the future will know more about your cycling than you and your coach. With access to so many measurements, it will become your friendly resident cycling expert. This expert will be able to guide you in all aspects of how to most effectively set up, pedal and train on your bike. Your power meter’s expertise will lie in its software and the data it gathers on you and your bike. The input from you will be minimal (apart from the effort involved in riding your bike). It will provide a comprehensive analysis of your every pedal revolution. If you want to know that your riding position is correct, take a short video clip with your phone while you ride for a few minutes on your indoor trainer. By scanning your image and using its sensors, your power meter will be able to find the optimal position for you as you ride. If you want to check that you are pedalling efficiently, your power meter will give you immediate feedback on your cycling technique and how to improve it. If you want to know how hard you have to ride to complete a 25-mile time trial in under an hour or an alpine sportive within the time limit, your power meter will calculate it and show you. If you are wondering whether changing equipment will allow you to ride faster, put your power meter into equipment testing mode and it will tell you.

Your biggest gains will come from your power meter’s expert guidance once you start training. After your first training ride, your power meter will start analysing your training data. It will then use this to calculate your expected performance changes. It will not stop there though. Crunching through large amounts of data is something that computers do much more effectively than humans. It will identify patterns and relationships in your training data in a way that outperforms the capabilities of even the best cycle coach. As a consequence of its analysis of your previous training sessions, your power meter will also be able to advise you on what to do next. Using a power meter in the future will mean you have no need to worry about when, how long or how hard you should train. Your power meter will be able to calculate all this for you, based on analysis of your own personal training data.

Once you start a training session, your power meter will guide you along the way with more than route navigation. It will be able to prescribe your training intensity moment by moment, like a coach instructing you: go harder up here, pedal easier down there, hold this effort for another mile, and then pedal easily to recover. At the end of your training session, you’ll get immediate feedback on how well you have trained. Finally, your power meter will calculate when you should next ride for maximum training benefit.

The expert power meter of the future may sound rather fanciful, but my current research is focused on making this a reality. Reaching this future was precisely what first motivated me to study sports science more than twenty-five years ago. For many of the intervening years the way forward has not always been clear. But now advances in technology, my current research and the experience gained along the way suggest this future is not so far off. I am confident that you will not have to wait another quarter of a century to experience some form of expert power meter.

As I return to the present, it is clear that there is a training predicament. The science behind cycle training and racing has advanced considerably in the past twenty years. Now you can measure accurately what happens during training and racing directly from your bike. The Internet provides a significant repository of power meter files from a wide range of different cycling events for you to learn from. But your power meter is not yet smart enough to make this process really simple and do all the analysis for you. One day, power meters will provide a complete expert solution for bike training and racing. But with a little knowledge you can already easily use your power meter to help you make better decisions about your training and racing. From my experience and research, there are plenty of simple things that you can do to make your training with a power meter more effective. This book will tell you how.

CHAPTER ONE

AN OVERVIEW OF TRAINING WITH POWER METERS

I have been privileged to learn a lot by working with elite riders and their coaches during my career. In particular, I have seen first hand how Britain’s elite cycling programme has developed from a struggling minority sport to one of the most successful in the world. The concepts behind this success are very simple: clear goal setting and good planning. Anyone who is familiar with the success that Britain’s best cyclists have achieved will tell you this. You can do this too and benefit in the same way with your training. I am afraid this does not mean that you will become an Olympic or Tour de France champion. But if you have ambition, use goal setting and plan your training effectively, I am confident that you will be surprised by what you can achieve.

This book is about training and using a power meter to help translate your goals and plans into improved performance. It does not matter why you train – you should still find the information relevant as long as you are motivated to improve. Your current level of fitness and how far you are able to progress are not important. From my experience I have found it impossible to tell how far an individual can improve. I have on several occasions helped riders achieve new PBs after they have been told they have reached the limits of their potential. Using your power meter can help you find that extra little bit. Used thoughtfully it is a potent training tool. But it is important to recognize that it is how, not whether, you use it that makes the difference. Your power meter can help you in many aspects of your training, from preparation and planning beforehand, to monitoring and analysis afterwards. It acts like a magnifying glass with which to examine your training.

THIS BOOK

Getting the most from training with your power meter is about much more than what you do on your bike. The process begins before you start your training session and continues after you have stopped riding. Your power meter can help you develop, analyse and refine your whole training strategy. But to do so you need to have a training strategy and a reasonable grasp of the fundamental principles of training.

Having a training strategy means that you approach your training in a thoughtful manner. It also implies that you continually seek ways to improve your training. Grasping the fundamental principles of training is about learning to manage your training, not about becoming a coach. Although I do suggest you seek the support of a coach if you really want to push your limits, for the purposes of this book I am going to assume that you are coaching yourself.

Regardless of whether or not you have a coach, to use a power meter well it is helpful to understand the principles of the training process. The difference between being a rider and a coach is analogous to being a car driver or a mechanic on a long road trip. To complete the journey you do not need a mechanic’s detailed understanding of how your car’s engine works – you just have to be able to drive your car (or in this case ride your bike) to your destination.

Your training strategy can be thought of as a three-step process. First you set your goals, next you plan your training programme, and after training you evaluate and refine your training programme. At each of these three steps your power meter can help refine the process.

Developing your training strategy is a straightforward process but there are some guidelines worth following to make the most of your training. Start by setting yourself goals that you then use to plan and programme your training. Review the strengths and weaknesses in your current level of fitness or performance, and take into account the time and any other resources you need for training. This information provides the key components to planning your training programme. Once you have written out your programme and started training, resist the temptation to follow it too rigidly. Check routinely that you are training as intended and that the effects are as expected. Keep looking for ways to improve your training further.

Training with your power meter helps you implement this strategy in many ways. Your goals can be set in quantifiable terms so that you can specify precisely the details of your training. Before your training begins you can plan the specific power output at which you intend to train and for how long, given any type of session. During the training session your power meter can act to remind you of these training targets and to provide immediate feedback on where you are relative to them. And after your training session you will be able to check that you were actually hitting the numbers you planned. With a little experience you will be able to use your power meter to obtain objective assessments of your strengths and weaknesses in training and racing.

Training with a power meter is also a journey of self-discovery. For example, you will learn how hard you can work from the start of a session, and you will be able to see the consequences in terms of your power output, speed, heart rate and effort. With a power meter, pacing your effort in training and races becomes more measured and controlled. Over time the cumulative benefit of training with a power meter should be apparent as it shows you how your fitness has changed.

Keeping the principles of training in mind will help guide you in your training. The theory of training based around overload, recovery, overcompensation and progression is straightforward (covered in more depth in Chapter 4).You can use your power meter to ensure that your training overload is appropriate and that your recovery is sufficient. You can use Training Intensity Bands (TIBs) to structure your training and guide the use of your power meter out on the road. Using TIBs in your training provides a simple scheme for you to specify and monitor your target power output in every training session. It makes communication and planning around your training easier, too. If your training progresses well, your power meter will display clear signs of overcompensation in your fitness. Equally, analysis of your power meter data can help identify signs of staleness and overtraining if things are not quite right.

This brief overview has set out the broad strategy for this book. I aim to help you think about your cycling goals, your plans to achieve them and, of course, how training with a power meter can underpin your success. In the next chapter I will explore the relationship between work and power, and why you measure these on your bike.

With a little experience you will be able to use your power meter to obtain objective assessments of your strengths and weaknesses in training and racing.

CHAPTER TWO

THE POWER METER

WORK AND POWER: HOW IT’S ALL ABOUT THE RATE

You are familiar I’m sure with the concept that when you do work, whether it is lifting weights or training on your bike, you use energy. The more work you do, the more energy you burn. When you have finished working you eat food and replace the energy you have used. Energy and work are measured in joules (or its equivalent in calories). Your power meter measures how much work you do on your bike but you should not normally be particularly interested in this. Instead, you should prefer to focus on the rate at which you work or, to use its proper name, power.

Let us examine in a little more detail why you are not primarily interested in measuring the joules or calories you use in training on your bike. Imagine there is a wheelbarrow full of rocks that weigh the same as you and you have been challenged to move them to the top of a hill. It is quite a bit of work (or energy) to get those rocks to the hilltop. In fact, you can calculate quite accurately exactly how many joules are involved in this challenge. All you need to do is measure the weight of your rocks and the height of the hill, and multiply them (by gravity, which is the force we are overcoming in this example). The physics of calculating the amount of work you do when cycling up the hill are exactly the same: it is also the product of your weight (the same as the rocks), the height of the hill and gravity. I have used this example as it does not matter whether you are considering moving your rocks up the hill or cycling up the hill: the work required in both examples is the same.

When you are halfway up the hill you notice other people have taken the same challenge (you can choose now whether you prefer to think in terms of rocks or cycling). Not wanting to be outdone, you work harder to speed up. With considerable extra effort, you manage to get to the top first. Now let us compare the work of getting to halfway nice and steadily with that of getting from halfway to the top as fast you can. Was it the same (as you travelled half the hill each time) or was it different (the second half felt much more stressful as you pushed harder)?

This question is about the amount of work (or energy) you used. Comparing the work of getting from the bottom to halfway with halfway to the top gives the same result: it is half the hill both times. So when you are cycling up a hill, how fast you climb it does not change the total amount of work you do. To increase the amount of work you would either have to move more rocks (in other words put weight on) or pick a higher hill. Even then you probably would not mind the extra work too much, as long as you can compensate by taking a little longer. The point of this example is that knowing the total amount of work you complete does not tell you how hard you have been working. So what is the reason that the second half of the hill felt much harder? It is because you increased the rate or the speed at which you went up hill. You did the same amount of work but faster, or in other words you increased your work rate. Increasing your work rate is what this book is all about!

Measuring your work rate when you train is the primary function of your power meter.

Measuring your work rate when you train is the primary function of your power meter. Power is the measurement of work rate. Your power output is measured in watts (W). You may be familiar with the watt as a measure of power output in other contexts too, as it is the standard way of quantifying power output. A number of household devices use watts to describe how powerful they are or the rate at which they consume energy – Table 1 has some examples. Somebody (or something) with a high power output can do a lot of work very fast.

On your bike you are the engine. Your power output is a measure of the engine size with which you propel your bike. The higher your power output, the bigger your engine and the faster you go. Your power output is determined by two factors: the force with which you press on your pedals and your cadence (how fast you spin your pedals). You can increase your power output by pressing harder on your pedals. Alternatively, pedalling faster with the same force will also increase your power output.

There is a direct relationship between your pedal force, your cadence and your power output. This relationship means that you can use different combinations of pedal force and cadence to produce the same power output. For example, you could produce the same training power output with a low cadence and high pedal forces, or with a high cadence and low pedal forces. You might consider the implications of this for your training.

Table 1. HOW DO YOU COMPARE?

Maximum Power (W)

On a bike

Light bulb

  100

Easy ride

Television

  170

Medium ride

Computer

  200

Tempo ride

Large television

  280

Elite race

Microwave

  800

Team pursuit

Drill

  900

Women’s road sprint

Electric hob ring

1400

Men’s road sprint

Kettle

2200

Track sprint

Washing machine

3000

Standing start

There is another important point about the relationship between pedal force, cadence and power output that you will notice when you are out on your bike: this is what happens to your power output when you stop pedalling, in other words when you freewheel. Because power output is a measure of work rate, when you stop pedalling it immediately falls to zero. Equally, if you do not apply any force to the pedals (for example if your chain comes off), your power output again falls to zero.

WHY USE A POWER METER?

Given the range of different devices that are available to help you record your training, you may wonder why you should consider using a power meter. Using a bike computer to monitor your training time and distance provides a much cheaper alternative, so could it prove equivalent? The short answer is ‘no’. Currently there is no alternative to the power meter that provides as much or as important information for your training. This is a key question so I will explain more fully.

In order to train effectively it is helpful to plan and monitor your training intensity.

First consider what can be measured without a power meter. There are many training devices that enable you to record your basic training outcomes. Whilst out on your bike you can easily monitor simple variables such as your training time, distance, speed and even metres climbed. To do this there is a wide range of devices available including bike computers, GPS devices and so on. If you have a smartphone you can probably install a cheap or free app to record these too. It is also comparatively straightforward to obtain a more detailed recording of your training incorporating more technical variables such as your cadence and heart rate. Typically, both these measurements will require you to purchase additional equipment or sensors specifically for the purpose. Even so, this equipment is still relatively affordable for most people. Given that you can easily measure such a number of training variables, going to further trouble and expense in order to measure power output might seem superfluous. Let us explore why training with a power meter can be sufficiently useful to justify the extra cost.

In order to train effectively it is helpful to plan and monitor how hard you work in each training session, otherwise known as your training intensity. The more detailed reasons for this and other principles of training I will discuss in the subsequent chapters. As you work harder on your bike you will go faster and therefore cover more distance. So you could use training time, distance and speed in order to monitor and evaluate your training intensity. Indeed, many people have and continue to use these measures very successfully to inform their training practice. But if you have tried monitoring your training distance and speed in the past, you will already know the limitation of using these measurements to gauge how hard you have worked in training. Your training distance and speed are not only related to how hard you train. Several other factors also exert a powerful influence over how far or fast you can ride. These factors include variables such as air pressure, humidity and temperature, wind speed and direction, the road gradient and road surface characteristics, your riding position and your clothing. Importantly, most of these factors can change continuously throughout a ride and these changes are not easy to measure. It is impractical to try and take account of these changes in order to plan your training based simply on speed or distance. Equally, you may want to monitor and evaluate your training over a period of time, but it is often almost impossible to calculate whether the change in your training speed between two sessions was due to a difference in how hard you worked, or a change in one or more of the variables above.

Using a power meter removes this uncertainty. By training with a power meter you can quantify precisely how hard you are working at any given moment regardless of the terrain and other environmental conditions. After your training is complete, your power output data provides the basis for a simple comparison with previous sessions. You can determine easily whether you achieved the desired training intensity. You can even calculate whether any changes in how fast or far you trained were due to variation in your fitness, training intensity, or the terrain or other environmental factors.

In addition to power output, you can gauge how hard you are working by measuring your heart rate. Although training by heart rate is not the same as measuring power output, it is worth discussing further. The reason for considering this is that a heart rate monitor measures something quite different from a bike computer or GPS device, and the combination of a power meter and heart rate monitor is better than either on its own. Bike computers and GPS devices record how far and fast you went in your training session. Using a heart rate monitor will tell you about how hard your body is working. Knowing how hard your body is working tells you your training intensity. Therefore, when you train with a heart rate monitor you do not need to be concerned about how your speed is affected by wind, hills or road surface. This is because you can plan based on a target training intensity rather than speed or distance. Regardless of whether you are grinding uphill or coasting downhill, battling headwinds or floating on tailwinds, you can easily focus on hitting your target training intensity if it is specified by your heart rate not your speed.