Glucose and glycogen can be essential for athletic performance, helping to boost your endurance. It can also aid in the recovery of your muscles after your workout.
How long does glycogen last? The short answer is that it’s between 90 minutes and 2 hours when cycling. For a fuller answer, keep reading!
Before you know how long it will last and how it can help, you should probably know what exactly it is. We’ve put some information together to give you some insight into how glucose and glycogen can improve your training, as well as some tips on how to maximize your glycogen levels when working out.
Glycogen is the stored form of glucose in the body. It is held as a reserve in the liver and released as glucose when your body needs energy. Muscles also store glycogen, with around three-quarters of a body’s glycogen reserves stored within muscles. But a higher concentration of glycogen is stored in the liver.
Your brain uses glucose in everyday life and it’s the only fuel normally used by the brain. This means the body’s glycogen stores are important for fueling the brain with glucose, as well as acting as a device to regulate normal blood-glucose levels. The brain itself does not store glycogen so this needs to be replenished to the muscles daily for the brain to use the glucose.
Glycogen can be created through the consumption of carbohydrates. If your body does not immediately require the energy and glucose from the carbohydrates, the excess carbohydrates are stored in your muscles as glycogen for future use.
Glucose is a type of sugar that can come from food and can be made by the body. Insulin is what helps the glucose move to the cells that need it for energy.
When taking part in exercise, your body uses up the glycogen stores in your muscles. The glycogen is released from the muscles as glucose and is oxidized for use by your muscles’ cells right away.
During high-intensity anaerobic exercise, your body can rely on glycogen stores without the use of oxygen.
Consuming carbohydrates can affect the amount of glycogen stored in your body. The more carbohydrates you consume, technically the more glycogen reserves you can have. A higher level of physical fitness can also improve your body’s glycogen stores, with healthy muscles able to store more glycogen than damaged ones.
Athletes require glycogen for intense physical activity. Immediately after exercise, glycogenesis begins, which means your cells are preparing to replace the lost glycogen through carbohydrate intake and your body’s release of insulin from the pancreas.
If you consume carbohydrates immediately after intense exercise, this can trigger increased rates of glycogen synthesis to replenish the lost glycogen stores due to your elevated metabolism created by the high-intensity workout.
By consuming a high-carbohydrate drink or snack immediately after your workout, it will help to restore the glycogen levels more efficiently which can speed up your muscle recovery.
The length of time that glycogen will last will generally depend on the level of intensity of your cycling and your personal fitness level. In many cases, your glycogen levels will usually start to run out between 90 minutes and two hours.
The faster and harder you ride, the quicker your glycogen reserves will run out and the sooner you’ll have to replenish them. This is why it can be a good idea to drink an energy drink or a high-carbohydrate snack in the middle of your ride, as this can help restore some of your lost glycogen so that you can continue at the same intensity.
In fact, we think snacking small and regular (every hour or so) is optimal. But your mileage may vary. Read more about it here.
At a slow, casual cycling pace, you may burn around a gram per minute compared to three grams per minute if you’re cycling at racing speed.
Read more: Can you keep fit by riding to work?
When glycogen stores in your muscles are low, it means your pace is reduced and you can’t continue at the same level of intensity as fatigue will set in. This will also mean that your body will have to use fuel from elsewhere to make it through the rest of the activity.
This can mean your body starts to break down protein or amino acids in order to convert them into glucose to provide fuel.
Low levels of glycogen during endurance activities can result in painful and damaged muscles, as your body starts to use the muscle mass to provide fuel. This means you may not be able to train the next day.
If you fail to consume enough carbohydrates after the exercise to replenish the muscle glycogen stores, the amount of glycogen held in your muscles will steadily start to drop over the next few days. This could then affect your future cycling performance.
It can be important to maintain your glycogen levels while you’re cycling so that you can maintain your desired pace. This can mean refueling with carbohydrates during your ride. Generally, you should consume carbohydrates every hour of your workout – roughly around 30 to 60 grams for each hour of your endurance ride.
The level of exercise you do can also have an effect on your glycogen stores, which can then affect the amount of carbohydrates you will need to consume to replenish the glycogen stores you’ve depleted.
Typically, if you’re cycling at a moderate pace, where you can still hold a conversation, you should consume around 2.5 to 3.5 grams of carbohydrate per pound of body weight per day. In this case, around half of your consumed daily calories should be carbohydrates.
If your cycling intensity is low then your glycogen reserves can usually be replenished by eating a normal healthy diet, without having to increase your intake of carbohydrates. This is because the glycogen expenditure is lower or the same as the amount your body makes from the consumption of carbohydrates.
If you’re cycling at a very high intensity, it’s recommended that you consume around 4 to 6 grams of carbohydrate per pound of body weight, including high-carbohydrate meals and snacks post-workout.
Remember, the amount of carbohydrates you should consume will generally correlate with the amount of energy you expend. So, if your workout is more intense than normal, your calorie and carbohydrate intake should increase.
It can also be important to rest after an intense training session, as resting, in addition to sufficient intake of carbohydrates, has been shown to increase the levels of glycogen stored within the muscles.
By overworking the muscles, you could cause a reduction in the amount of glycogen that’s able to be stored in the muscle. This means that even with the increased consumption of carbohydrates, the glycogen levels may not be able to increase to the desired amounts. A sufficient rest, for example, 24 hours, can help to repair the muscles as well as restore muscle glycogen.
Glycogen is essential for the human body, whether you’re taking part in intense anaerobic exercises or simply a casual stroll. As we all know, carbohydrates provide energy. And as we now know, carbohydrates are the source of glycogen which can provide us with the fuel to power through a race or weekend bike ride.
So it can be important to maintain sufficient levels of glycogen before, during, and after your workout, as well as giving yourself a decent rest. You know your muscles will thank you for it.