Recovery Nutrition

Rehydration

Sweating is a natural reaction during exercise to prevent the body from overheating, but it does mean we lose fluid and salts (electrolytes) that need to be replaced. Being even slightly dehydrated (as little as 2 % body weight lost as sweat) can negatively impact aspects of performance such as decision-making, concentration and reaction times. Sweat rates vary from person to person, so it can be useful to develop a personalised fluid strategy based on training sessions. Hydrating after exercise is essential for our recovery but being well hydrated before a workout can also help to make our rehydration strategy most effective. Measuring your body weight before exercise, when adequately hydrated and then again post exercise, can help to determine how much fluid has been lost through sweat. 

Some general tips include:

• Ensure you are hydrated when beginning a sports session by drinking 1.5-2 L of fluid over the 24 hours beforehand.
• Monitor urine colour; a straw yellow colour is an indicator of good hydration levels.
• Drink about 500 ml water 2 hours before exercise to allow time to urinate if needed and always bring your own bottle in your training kit.
• Don’t wait to drink until you feel thirsty. Drink small sips of water at breaks of activity e.g. 100-200 ml every 15-20 minutes.
• If exercising longer than 60 minutes, a sports drink may be useful to provide carbohydrates and electrolytes; or you can make your own drink by mixing 800 ml of water, 200 ml of sugar-containing fruit squash and a pinch of salt.
• Rehydrate after sport to replace fluid lost e.g. 400-800 ml per hour of exercise completed. Water or skimmed milk are good options. For intense sessions, if a specific amount of body weight has been lost through sweating, it is generally recommended to replace 150% of losses over five hours e.g. if you lose 1kg of fluid, consume 1.5L.

As we lose electrolytes (sodium, potassium and chloride) as ‘body salts’ when we sweat, these need to be replaced by consuming foods or fluids containing electrolytes. For example, include a pinch of table salt (sodium chloride) to season your recovery meal; or choose milk which naturally contains potassium.

Refuel

Exercise demands energy and the main fuel burned and depleted during exercise is carbohydrate. The carbohydrate that is burned comes from your muscles and liver (in the form of glycogen) and your blood (in the form of the blood sugar, glucose). Unlike our fat stores, carbohydrate stores in the body are much more limited and depletion of glycogen stores during prolonged exercise is closely linked to fatigue. Therefore, during prolonged bouts of exercise, such as cycling for more than two hours, carbohydrate consumption can help to delay fatigue through maintaining blood glucose levels. Sports drinks or gels are often used as a convenient method in these cases.

For most sports people, carbohydrate refuelling should begin shortly after exercise and is faster during the first few hours. Complete muscle glycogen replenishment can take about 24 hours. Aim to eat carbohydrate-based foods with some protein within 30-60 minutes after exercise to begin refuelling energy stores and assisting muscle repair. Follow up with a substantial meal based on carbohydrate foods such as bread, pasta, rice or potatoes; paired with lean protein sources such as meat, fish or poultry; and include a variety of vegetables to contribute to vitamin and mineral intakes. A carbohydrate intake of 1.2g /kg/hour is generally recommended.

Milk is a popular drink in the recovery window following exercise due to its unique composition. Due to their higher carbohydrate content, some athletes opt for flavoured milks, such as chocolate milk. It has a similar nutrition profile compared to low-fat milk in terms of fat, protein, vitamins and minerals but offers an additional 7 g per 100 ml of carbohydrate due to added sugars.

Repair

Muscle protein breakdown is a natural response to intense or prolonged physical activity and most people at some stage, will have experienced sore muscles in the days following a tough exercise session. This delayed-onset muscle soreness results from small tears to muscle fibres. Exercise therefore acts as a stimulus for building stronger muscles as the muscle groups need to repair and adapt to meet repeated performance demands.

Muscle damage can lead to reduced power and loss of strength so adequate muscle repair is an essential part of the recovery process. Short term muscle recovery helps to prevent injury and ensure that performance capacity has returned before the next session. Long term training adaption refers to the recovery process which leads to enhanced performance from improvements in the muscular and cardiovascular systems.

When people talk about muscle recovery nutrition, many topics get attention, including antioxidants, tart cherry juice, foam rolling and novel recovery shakes. While the research is building in these areas, protein is still the key ingredient for recovery as it provides amino acids which assist muscle growth and maintenance. Amino acids are the components of protein which form the building blocks of new body proteins, such as muscle tissue.

Timing and quality are important when it comes to protein and the optimal approach is to spread intakes across the day rather than consuming a large amount at one meal. This enables the body to supply a constant amount needed by active muscles throughout the day. Consuming protein (approximately 20-25 g) following an intense session is particularly useful to assist muscle growth and repair. Protein requirements are estimated based on individual body weight; with slight variations depending on the type and intensity of activity. General ranges for daily protein requirements per kilogram of body weight are provided below: