Fast glycogen regeneration after training: Liver refuels faster than muscles

New insights into energy supply after intensive endurance training

Who doesn't know this feeling? After a long bike ride or a hard run, your legs feel exhausted and your energy stores are depleted. But how quickly can these stores replenish themselves? A recent study by Fuchs et al. (2025) shows that the liver builds up glycogen significantly faster than the muscles, even with a very high carbohydrate intake of 10 g per kilogram of body weight.

This is how the study was structured.

Twelve experienced cyclists trained until exhaustion and then received carbohydrates in the form of sucrose (glucose and fructose) over 12 hours. The amount of glycogen in the liver and muscles was determined using high-resolution measurement methods.

The surprising result.

• Liver glycogen was completely replenished after 6 hours, in some cases even exceeding the initial level.
• Muscle glycogen only reached about 70% of the initial value after 12 hours.
  This shows that the liver is a faster storage site and plays a central role in energy supply.

Why this is important for endurance athletes

The fructose component is preferentially processed in the liver, while glucose takes longer to penetrate the muscles. For optimal regeneration, a combination of glucose and fructose is therefore recommended, ideally in small portions every 30–60 minutes in the first few hours after training. However, fructose is significantly easier and faster to reprocess in the liver than glucose, especially since glucose additionally requires potassium to optimally replenish muscle glycogen stores (Editor's note).

Practical tips for your recovery with SportBrennstoff

• Immediately after training, drink a SportBrennstoff ERHOLUNG recovery drink with dextrose and potassium for rapid regeneration of muscle glycogen stores.
• Supplement with a carbohydrate drink (for example, SportFuel RESISTANCE ) with a glucose:fructose ratio of 2:1 30 to 60 minutes later.
• In the following hours, supplement your meals with carbohydrate-rich foods such as rice, potatoes, or pasta.
• Take the opportunity to achieve a balanced diet with fruit after about 2 hours.
• Ensure adequate electrolyte intake and easily digestible snacks, even overnight or later in the evening.

With this strategy, you support the rapid regeneration of liver glycogen and ensure a continuous replenishment of your muscle stores.

Conclusion

The liver recovers faster than the muscles – an important finding for professional endurance athletes and ambitious hobby athletes. Accordingly, special attention should be paid to the recovery of muscle glycogen stores. Use science and tailor your nutrition to maximize your performance and recovery. SportBrennstoff supports you with optimal sports nutrition on your path to success.

Source:

Fuchs, C.J., Veeraiah, P., Hermans, W.J.H., Brauwers, B., Voncken, R., Brouwers, K., Petrick, H.L., Hendriks, F.K., Bels, J.L.M., van den Hurk, J., Weber, J., Senden, J.M., Smith, F.E., Thelwall, P.E., Prompers, J.J. and van Loon, L.J.C. (2025), Carbohydrate intake of 10 g/kg body mass rapidly replenishes liver, but not muscle glycogen contents, during 12 h of post-exercise recovery in well-trained cyclists. J Physiol. https://doi.org/10.1113/JP289115