No matter what your chosen form of exercise, whether it’s a 10 mile run, a weights session or a rugby match, refuelling correctly following a training session is crucial to ensure optimal recovery.
During exercise, your body uses up your glycogen stores in the muscles and liver to provide energy. Also the proteins found in our muscles are broken down and damaged, the combination of these two processes makes you fatigued and unable to perform at your maximum. You need to counter these effects quickly to ensure you are back in training as quickly as possible.
This is all about restoring your energy. Energy comes from glycogen, which we get in our diets through carbohydrates. Carbohydrate consumed immediately after exercise has been shown to be more effective at replenishing glycogen than consuming no carbohydrates until a few hours post-exercise (Burke et al, 2011). The best type of carbohydrates to consume immediately post-exercise are high-GI carbohydrates such as cereal, white bread and honey as they are rapidly digested, providing an instant source of glycogen. They also cause a spike in insulin levels which is beneficial in promoting protein synthesis, by increasing the uptake of glucose and amino acids.
Low-GI carbohydrates such as brown rice and sweet potatoes should be consumed throughout the day in order to build up and maintain glycogen stores in preparation for the next training session.
Protein is required following exercise in order to re-synthesise the muscle tissue which has been broken down or damaged, a process called catabolism. It is important that the body is provided with a quick source of protein to prevent further catabolism and kick-start its reformation. Consuming whey protein is ideal, as it is fast-digesting protein source, providing the muscles with a speedy supply of amino acids which are utilised to synthesise muscle proteins.
With breakdown prevented, rebuilding muscles is the next step. Amino acids are the building blocks of proteins, which repair the muscle. It is important to take on Branch-Chain Amino acids (BCAAs) as the body is unable to synthesise these by itself, so we need to get them from our diets. BCAAs aid recovery by causing increases in insulin secretion which promotes a greater uptake of amino acids and glucose by the muscles. Once they have been absorbed by the muscle they can be used to synthesise protein. Studies have found that Leucine (one of the three BCAAs, with Isoleucine and Valine), is able to stimulate muscle protein synthesis (Norton & Layman, 2006).
Timing is crucial for recovery. The first 45 minutes after training, often referred to as the “metabolic window”, has been suggested to be an important timeframe for making the transition from a catabolic state to an anabolic state (where glycogen stores and proteins are synthesised) through the consumption of carbohydrates, protein and amino acids.
Whilst the existence of this 45 minute window remains up for debate, it makes sense to consume sources of protein/amino acids and carbohydrate as soon after training as possible in order to prevent further protein breakdown and allow for glycogen and protein to be synthesised.
Studies have shown that the consumption of a combination of carbohydrate, protein and BCAA’s post-exercise has been found to be more effective than intake of carbohydrates alone in aiding muscle anabolism (Koopman et al, 2005) and in replenishing glycogen stores (Detko et al, 2013). You can get this combination through foods, though it is easier to achieve the correct intake through sports nutrition.
GlycoSource has been designed to provide an optimised balance of these three key requirements, containing low- and high-GI carbs, whey protein and leucine. Our studies have shown that the addition of the protein and amino acids providing a 30% more effective recovery than through carbohydrates alone.