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How to hit race weight

Race weight
Sam Challis
27 May 2016

For most cyclists, losing weight is a sure-fire way to improve performance, but the path to enlightenment is littered with pitfalls.

Spending thousands of pounds upgrading your kit is certain to improve your performance on the bike – but it’s not the best way. For the majority of us, there are greater performance gains to be had by losing body weight, because while shedding weight from your equipment has the potential to save a few hundred grams, stripping unnecessary weight from your body gives you the scope to save thousands. 

The reason weight has such an impact on performance lies in its relationship with power. Accelerating a given weight or moving it uphill requires power, so it follows that cutting weight from an object will see it travel faster for the same amount of power. In other words, the lighter you are the quicker you’ll go for a similar effort. This is quantified by your watts-per-kilo (W/kg) figure. Due to this being a relative measure, in that it allows any cyclist to be fairly compared to another, it is one of the most coveted values in cycling.

Weight loss for athletes remains a minefield of fact, fiction and contradictory evidence, so Cyclist decided the best way to get to the truth was to consult the experts and then test the theories for ourselves. That’s how I find myself being prodded, scanned, measured, tested and re-tested, all with a specific goal in mind: to lose weight without any loss of power.

Energy – a balancing act

It seems logical to start by examining the basic science that underpins weight loss. We derive most of our energy from three types of nutrient: carbohydrate, fat and protein. This energy is measured in kilojoules or kilocalories (often shortened to just calories, or the abbreviation kcal) and different nutrients have different energy densities: fat has 9kcal per gram, while carbohydrates and protein have 4kcal per gram. 

This energy is used by our bodies to fuel three things: metabolism (the chemical processes that occur in our cells to keep us alive), thermogenesis (the production of heat) and muscular contraction (the production of movement). The supply of energy to the body through food, measured against its use of energy discussed above, creates an ‘energy balance’.

‘There is a tendency to get really complicated about this, but it’s really quite simple,’ says Dr Brad Elliot, lecturer in physiology at the University of Westminster. ‘I am a physiologist but I like to think in terms of physics. At its most basic level your energy balance is a case of calories in versus calories out. Essentially we are just lots and lots of cells, all of which need energy. If you have a positive energy balance, cells are created, and if you have a negative energy balance, cells are lost or get smaller. And obviously fewer cells means less weight.’

This all sounds simple enough: if I eat fewer calories than I use, I’ll lose weight and my performance will improve, right? Wrong.

‘There is an important distinction to make here,’ says Pav Bryan, cycling coach at Alex Dowsett’s performance venture, Cyclism. ‘We are looking specifically for fat loss, not weight loss. Losing fat will favourably change your body composition, and therefore your power-to-weight ratio, while simply losing weight might not affect it at all. Fat is non-functional body weight, so we can afford to lose it. But general weight loss can also include the loss of lean tissue, so although you may be lighter, you’ll have less muscle and your performance is likely to remain at a similar level.’

This happens because when you are operating at a negative energy balance, your body must make up the deficit from somewhere, and it does so not only by burning body fat but also by oxidising muscle tissue. Through a process called gluconeogenesis, muscle proteins are turned into carbohydrate energy. I hardly have the muscle to spare, so how do I make sure I’m burning fat and not muscle? The short answer is that I can’t, but what I can do is minimise the amount of lean mass lost. 

‘To lose fat you simply must be at a calorie deficit,’ says dietician Jo Travers of the Harley Street Nutritionist. ‘However, by consuming carbohydrate in a correct manner, the rate of fat loss will vastly exceed the rate of lean tissue loss.’

Her comment on correct carbohydrate consumption piques my interest. This macronutrient is widely held up as the enemy of fat loss, but according to Travers this simply isn’t true, and particularly not for cyclists. 

‘Your body has evolved to use carbohydrate as your primary energy source, so when you don’t have enough available, your body will switch to using a different kind of fuel. Yes, you will lose fat, but crucially you cannot protect your lean body mass from being broken down as well.’

This is an intriguing counterpoint to a slew of contemporary weight loss information – substituting carbohydrate for more protein is a popular method of losing weight, but Travers explains that for a cyclist this is not always the most effective way. 

‘Your body needs protein to make hormones and enzymes to build and repair cells that you damage during training, so if you’re using protein as an energy source it is incredibly wasteful. Energy to survive takes priority, so your body won’t say, “Oh, I won’t use this protein for energy, I’ll put it aside to make enzymes” – it will always inefficiently convert that protein to carbohydrate for energy. That wastes protein’s primary function and still doesn’t provide energy effectively enough for you to train properly.’

The fat question

With common advice on the consumption of carbohydrate and protein looking potentially misguided and irrelevant for cyclists, it should come as no surprise that dietary fat may not be the necessity for a cyclist that it is often portrayed as. 

‘Don’t get me wrong, you need a certain amount of fat, as it carries fat-soluble vitamins that are vital for optimal bodily function, including metabolism,’ says Travers. ‘But you only need about two teaspoons a day to function properly.’ 

In other words, as a cyclist there probably exists plenty of scope to cut fat from your diet, since all the energy you need can be supplied by carbohydrate and your body’s own fat stores. And with fat being highly calorie-dense, reducing the amount of fat you consume is likely to help in your quest for a negative energy balance.

Picking your way through the information and counter-information regarding each macronutrient is confusing enough, and there’s also conflicting information on the magnitude of the energy deficit required to best alter your body composition. 

‘That is really difficult to advise on because it depends on so many things that vary between individuals: muscle mass, metabolic rate, health status, even sleep,’ says Travers. ‘The best way is to start with a small deficit and experiment from there, making changes based on how your body responds. Ultimately, slow progress is better than fast inconsistency.’

With no unequivocal way to achieve fat loss that can be applied to everyone, the only way to determine an effective method for you is first-hand experience via a tailored programme.

A line in the sand

Setting baselines is an important aspect of any intervention. ‘If you want to make a change, then you have to know what you are changing from; it lets you see a measureable effect,’ says Elliott. In order to adjust my all-important energy balance, Elliot assesses my energy expenditure via a process called indirect calorimetry, which measures my inspired and expired gases to determine basal metabolic rate. Adjusting for my physical activity level, he determines that I burn approximately 3,800kcals a day.

Alongside energy expenditure, weight and body composition are the other key measurements. Pre- and post-intervention assessments play a massive part in accurately identifying what effect an intervention will have on my body, so I book a session in Elliott’s testing facility at the University of Westminster, using a Bod Pod. The Bod Pod is an accurate scale and uses a technique called ‘Air Displacement Plethysmography’ to determine body density, which is inserted into an algorithm to estimate body composition. 

Bizarrely, she suggests that I eat more food, not less...

After sitting in what resembles a large egg and listening to the machine whir and buzz, I discover that I’m 83kg, with 11% body fat. This is a far lower body fat level than I was expecting – the result I got previously from a DEXA X-ray body composition scan at Phil Chant’s BodyScan UK suggested I was nearer 18%. When I ask Chant about why there is such a large discrepancy between my results, he says, ‘As there is no direct way of measuring body fat – different methods estimate composition in different ways. The thing to remember is these machines are highly accurate from test to test, so there is an argument that it matters less about the numbers and more about the direction in which subsequent measurements are going.’

I also need to be able to assess changes to my power, so I run a turbo trainer protocol to determine my best output for 20 minutes, which comes in at 290 watts. If my intervention works, I will be able to equal or beat that at a lighter bodyweight, so long as I have lost non-functional weight. 

With baselines set, I can now embark on a programme that will hopefully turn me into a lighter rider at the end of it, without having lost any power.

Making the changes

Pav Bryan of Cyclism is the man to build my training plan. ‘It’s a real advantage to have a structured plan for a goal such as fat loss,’ says Bryan. ‘That way you know what you are doing and can measure progress, altering the structure depending on feedback and your body’s responses. Cyclism uses week-to-week plans, so that if you have an issue during a week and aren’t able to progress as you should, I can work out the best way to get you back on track very quickly.’

We decide to make the training plan one month in length, which is short enough to be easily manageable but long enough to hopefully show a definite change. ‘Ideally you want a big effect from a minimal impact on your lifestyle, which makes it easier for you to properly adhere to the plan,’ Bryan says.

In my case, that means training during my commute, an hour’s ride each way five days a week. ‘Yours is a useful situation to be in,’ says Bryan. ‘You have the time available to get some good fat loss-specific training in. If you were training for a distance event this might not be an ideal situation, but as your target is fat loss we have the scope to build in the intensity and power outputs you need to give you results.’

By the numbers
Workouts completed 42 Riding hours 34
Calories burned while exercising 54,222 Kilograms lost 1
Calories consumed 102,000 Drop in body fat 6%
Kilometres cycled 920 Wattage increase 5w

Bryan recommends that I gauge my rides using a power meter, as it takes the guesswork out of training intensity. ‘It is very difficult to know what intensity you are doing without a power meter. Basing intensity on other values such as heart rate is possible, but it’s subject to so many other variables. With a power meter you can almost always expect to do a certain power output and achieve a certain response from the body.’

My plan includes 10 sessions a week, three of which are high intensity, three at a low intensity, and four middling rides. I’d always been under the impression that to burn the most fat, I needed to exercise at a high intensity more often, but Bryan explains his thinking: ‘Hitting it hard all the time won’t let you recover well enough. When your glycogen stores are low, you are more likely to use muscle as fuel. Having the gentler sessions in there keeps you burning fat but also allows you to recover at the same time.’

Varying intensity is one method to promote recovery, but Bryan reiterates the importance of supporting it with an appropriate nutritional strategy. For this part of my programme, I turn to Travers. After a lengthy chat she observes that my diet is generally good: ‘You’re definitely getting enough protein and have sufficient variety of fruit and vegetables to get all the required vitamins and minerals. However, there are a few things missing. You are using more processed “sports nutrition” than I would ordinarily like to see – these products serve a purpose but is it far better to eat natural wholefoods. Also, you probably aren’t always getting your carbohydrate in at the right time, or enough total carbohydrate.’ 

After totting up an estimate of the calories I eat compared to my expected expenditure during the training programme, I calculate a daily deficit of nearly 800 calories. ‘This is far too aggressive,’ says Travers. ‘This sort of mismatch will mean you are almost empty of glycogen stores early in the week. You will be more likely to burn muscle and won’t be able to exercise at the intensity required.’ 

Bizarrely, she suggests that I eat more food, not less, with carbohydrate loaded around my rides at the beginning and end of the day.

‘It is about energy throughput,’ adds Bryan. ‘Lots of energy going in means lots of energy can be expended. Being better able to follow the intensity of the training plan means that fat loss is a result of the adaptation to exercise, as opposed to just being burned alongside lean tissue as a result of a deficit.’

The results

For my month-long plan, I stick to the exercise regime laid out by Bryan, and eat around 3,500kcals a day, inducing a fairly conservative 300kcal deficit.

By the time it’s all over, I feel that it has been a really positive experience. The carefully structured training plan gave my commute a defined purpose and the fact I was taking in more carbohydrate energy meant I cycled more intensely and had more consistent energy levels throughout the week. But what about the all-important fat-loss figure?

Before After
% Body Fat DEXA - 18 / Bodpod - 11  DEXA - 17 / Bodpod - 10
Weight (kg) 83 82
Fat mass (kg) 14 13
Muscle mass (kg) 63 63
20-minute power 290 295
FTP (w/kg) 3.35 3.45

After one month I have shed approximately 1kg of body fat, which isn’t as much as I might have hoped for, but which gives Bryan cause for optimism. 

‘Losing a kilogram in one month is good going,’ he says. ‘When you consider you also gained an extra 5 watts, it is a decent effort and shows your energy balance was managed well. Positively altering both sides of the power-to-weight measure will have a great effect on your cycling.’

Seeing an improvement in my performance figures has given me a taste for more, so how can I progress? ‘With your new power figure you could repeat the same structure at a slightly higher power output,’ says Bryan. ‘This progression would keep things moving in the right direction.’

I’ve seen my watts-per-kilo figure rise from 3.35 to 3.45 in a shade over four weeks. It’s not a vast change, but I still consider it to be significant, and I’m certainly riding stronger for longer. Apparently, to be competitive at the Tour de France you need a watts-per-kilo figure of around 6. Give me another few months…

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