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Lean up and cycle your carbs effectively - Practical advise for low glycogen training

Fasted training and the propensity to sell protein at every available source has now hit peak levels. The subject of fat-loss and body composition is one that naturally finds its way into magazines as January comes around. You'd almost think Mr Kipling and Men's Fitness were business partners like the clergy and the Undertaker! But what is the truth behind it all? and what if any are the benefits to cyclists?

Sober rides, fasted rides, glycogen depletion workouts... whatever you call them, they are certainly nothing new so don't let Men's Fiction tell you any different. How you achieve the best results from them is really what you want to know. Allow us to give you the benefit of our knowledge and experience of prescribing this form of training to all level of athlete.

Speed reading on energy systems

The body has three energy systems which can produce ATP (adenosine triphosphate), a compound of high energy found in the muscle at cell-level ... wait! This is a blog, not a dissertation.

Very high-intensity exercise uses very specific energy stored in the muscles.

High-intensity exercise uses blood glucose and muscle glycogen, both of which are from carbohydrates.

Low and medium intensity exercise uses blood glucose, muscle glycogen, fat, protein and oxygen.

So why did I tell you this part? Because the main energy system we want to tap into is the one which uses blood glucose, muscle glycogen, fat, protein and oxygen.

Speed endurance on carbohydrate-restricted periods

By reducing overall glycogen the body reacts in many different ways whilst under exercise load. The subject of carbohydrate manipulation on the diet of endurance athletes is one that's had multiple clinical studies over recent years. Whilst the results are not all positive there are many which are and can be used to great effect.

Studies indicate higher levels of adaptation at the muscle cell level when glycogen is in a partially depleted state. An important finding was that by restricting glycogen in the body prior to aerobic training we will see better post-exercise adaptations relating to

-increased skeletal muscle mitochondria

-increases in capillary density

-increased activity of the enzymes involved in the main metabolic pathways.

All of which can contribute to the development of the aerobic system.

Further to this, the studies have found that glycogen levels in the liver, not the muscles activate a neural response which in turn activates a higher level of fatty acids available for use. The result is greater fat burning capacity and potentially greater endurance.

A somewhat more real-world benefit is training your bodies ability to cope without food in emergency situations, such as missing a feed station in a stage race. Whilst, not an ideal scenario you will be better prepared mentally knowing you have some experience of the situation.


Like all studies, however, there is a flip-side!

What also came out of the multitude of reports I read whilst researching this subject is that training in a glycogen depleted state increases the bodies stress hormone, cortisol, which may have a negative effect on performance and also lead to increases in fat stores.

A second major outcome is an increase in activated protein kinase (AMPK) activity, which can lead to a limiting of muscle fibre hypertrophy (increase in muscle size). Not a good outcome if we intend to develop a riders lactate and anaerobic threshold.

OK! So how do I keep the positive benefits without getting those nasty negative outcomes?

  • Cortisol can be effectively reduced by having a good sleep pattern and ensuring you get enough rest off the bike. Consider a post-ride nap if you are a full-time rider, you'll still reap all the benefits and significantly reduce the downsides.

  • Restrict fasted rides to two per week, and build up your tolerance slowly.

  • Ensure you consume the main electrolytes of potassium, magnesium, calcium and sodium via a drink like a zero-cal type during fasted rides. Reduction in your electrolyte balance can exacerbate the lack of glycogen and induce more cortisol.

  • For more experienced riders, in particular, it is important to ingest protein whilst on the bike and subsequently. This can offset the risk of muscle wasting effects from increased AMPK activity.

A Practical plan for a good aerobic, glycogen depleted ride

Finally! The part where I explain a layman's plan of how to get the best effects from a training ride with restricted carbohydrates. In fact, I shall go one better and give you two, because one of the most frequent questions I get is how can I do this when I start work very early.

The first approach and which best suits a long weekend ride or a midweek ride for a full-time rider is as follows:-

  1. 6pm evening prior to fasted ride stop eating carbohydrates, you may consume protein prior to sleeping

  2. On the morning of the ride consume only an espresso coffee.

  3. Ride at a steady pace under your equivalent tempo heart or power. Z2 and below if you train to FTP zones. Consume nothing but zero-cal drinks with electrolytes.

  4. After approximately 1.5-2 hours eat solid food you brought high in nutrients and carbohydrate dense like a Veloforte bar.

  1. Continue your ride for anything up to 3-5 hours using a normal eating strategy of around 30-60g per hour of exercise. Increased efforts can be done inside this time-frame depending on experience and tolerance.

The second approach is one which is better suited to a rider who may not have the luxury of time during the week. So this session can be worked into a midweek training day once per week.

  1. 6pm evening prior to fasted ride stop eating carbohydrates, you may consume protein prior to sleeping

  2. On the morning of the ride consume only espresso again, if you have time! Otherwise, make your way to the turbo

  3. Alternate a 45-minute workout between 5 minutes at upper Z3 tempo and 5 minutes at Z2. Consume nothing but zero-cal drinks with electrolytes.

  4. After the session consume a carbohydrate-restricted breakfast. The key is to increase protein in this. Think 2 eggs and one small slice of rye toast.

  5. Snack on mostly protein sources throughout the day and reduce your lunch carbohydrates from normal by half. This will keep overall glycogen levels slightly impaired (glycogen levels only needs to be reduced by 30%-35% to achieve positive results). Think 1/2 baked potato with tuna instead of a whole.

  6. Carry out a structured one-hour workout either on the road or trainer. Be aware though that your performance will be impaired so selecting a session goal that fits will require forethought.

  7. Eat your evening meal as normal after the session.


Fasted rides are an excellent way of achieving accelerated, possibly improved gains in your aerobic system, and an efficient way of reducing both body-fat. Give them a go and build up your tolerance to them carefully.

If you would like our help at Elevation Coaching to formulate a progressive training plan to smash your goals and keep the fun in cycling get in touch at

We offer a range of bespoke plans ranging from £75.

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