This article provides everything you need to know about effective eating for post-exercise recovery, replenishment and rehydration.
Post-exercise Recovery Nutrition
Eating soon after exercise provides the body with the correct nutrients to fully recover, regenerate, and re-adapt, ready for the next training session. The physiological recovery of the body involves all the following processes…
* Refilling/refuelling of muscle and liver glycogen (carbohydrate) stores
* Replacing fluid and electrolytes lost in sweat
* Synthesising proteins for new muscle and cells involved in the repair and adaptation process
* Supporting the immune system to adapt to the challenges imposed by the completed exercise
The window of opportunity for heightened carbohydrate and protein utilisation is the body exists in the first 45 minutes post-exercise, and up to 2 hours post-exercise. Within 30-45 minutes of finishing a training session or race, it’s wise to consume something simple such as fresh fruit to replace glucose and make use of elevated glycogen synthase activity (the enzyme involved in glycogen replenishment). Taking a recovery drink is also a good option, as is a chicken, or vegetable broth, which helps to replace fluids and electrolytes. Studies have shown that consuming high GI carbohydrates, approximately 2g/kg of body weight (likely to be 100-150g for most male and female athletes), and 40g of protein within 2 hours after exercise speeds up the replenishment of glycogen stores and therefore speeds up recovery time (i.e. a 4:1 carbohydrate: protein ratio). It appears that the muscles are more receptive to (and retaining) carbohydrate during the two hours after exercise. A little protein enhances glycogen repletion. Practically speaking, a smoothie-type meal is always a great choice, as it’s easily and quickly digested and assimilated. However, simple and easy-to-digest nutritious food snacks are also high appropriate.
A basic post-race smoothie recipe for the blender might include the following:
1 large ripe banana
200g natural yogurt and water as needed
1 tsp of honey
1 tablespoon of ground flaxseeds, or shelled hempseeds or oatbran
A smoothie meal like this contains natural sugars for glycogen replenishment, a range of amino acids (including BCAAs) for protein resynthesis, antioxidants for cellular repair and regeneration, and omega-3 fatty acids too. This can be made in advance, and kept in a cooling flask.
Other alternative post-exercise meals include a breakfast meal, but with a little more protein, i.e. a bowl of oat porridge with natural yogurt, and nuts or seeds, a large rice (or quinoa) and fish/lentil/bean/turkey or chicken salad, with fresh fruits to follow, baked potatoes with beans or fish toppings, filled pitta breads, stews and soups.
N.B. Particular amino acids called the branched chain amino acids â€“ valine, leucine and isoleucine – or BCAAs are crucial for recovery. Branched chain amino acids are different from other amino acids that make up what we call â€œproteinâ€. There are 22 amino acids found in the human body, yet hundreds found in food. BCAAs are potent stimulants for building and repairing muscle. Lean meats and fish, as well as non-meat sources such as hempseeds are excellent sources of BCAAs.
After very long training sessions or races such as Ironman or half ironman, it’s important to continue a steady re-fuelling process. Research indicates that maximal muscle glycogen re-synthesis rates can be achieved by a continued feeding of carbohydrate at a rate of 1.2 g/kg/h (approximately 60-90g CHO) in relatively frequent (e.g. 15-30 min) intervals for up to 5 hours following exercise (Tarnopolsky et al., 2005). In food terms, this translates as eating 2 bananas, or other fresh fruits every 20-30 minutes or so. Better still, choosing a wider variety of post-race snacks ensures a mixture of carbohydrates, proteins, fats, vitamins, minerals and antioxidants is consumed to optimally re-fuel, repair, and revitalise the body. Ideas include omelette with rice and salad, fresh fruit salad with yogurt and seeds or nuts, a selection of dried figs, dates, raisins, blueberries and goji berries, or a small packet of oatcakes spread with cottage or ricotta cheese, peanut butter or almond butter and fruit spread.
5 on-the-go snacks that are easy to transport and perfect for post-exercise!
* Rice cakes and oatcakes spread with almond butter or peanut butter and banana slices. Stick 2 together and wrap in cling film to make for easy transporting.
* Healthy cereal/energy bars such as Nakd bars, or Clif bars
* Fresh chopped fruit in tubs – bananas, cored and sliced apples, grapes, peeled satsumas are the least messy and easiest to eat.
* Make-your-own snack packs of raisins, dates, figs, pumpkin seeds, almonds and dried apple slices
* Bagels or pitta breads with a savoury filling (e.g. tuna, egg, cheese, hummus, salad), or a sweet filling of fruit spread and banana, or honey and banana.
Research suggests that post-exercise rehydration is best achieved by consuming beverages that have a high sodium content (>60 mmol/L), in a volume equivalent to 150% of body mass loss. Gatorade recommend drinking 591ml fluid for every pound of weight lost. The amount of salt and electrolytes that need replenishing will depend on how much salt a person has taken in through liquids and solids during the race, and also how much a person has sweated out. The easiest way to effectively re-hydrate is to either choose a well-formulated recovery drink, or take a chicken, or vegetable broth with a little added sea salt, or sea vegetables that are high in all electrolyte minerals. Choosing a tasty, flavoursome drink that you like will help immensely to effectively rehydrate.
The importance of sleep for recoveryâ€¦
Sleep is the best supplement an athlete can take, in addition to a good diet, and well-structured training schedule. A lack of sleep increases stress hormone levels, interferes with the body’s normal appetite mechanisms, and decreases a person’s glucose tolerance – the reason(s) why sleep deprivation has been linked to weight (fat) gain, as well as numerous disease states. For the athlete, increased stress hormones (e.g. cortisol) prevent muscle and tissue regeneration. Getting adequate amounts of quality sleep, going to bed at the same time each night and getting up at the same time each morning is a wise addition to any athletes training and nutrition schedules. Working as closely to normal circadian (day/night) rhythms and establishing a proper routine is important to the body to establish healthy, and balanced hormonal patterns involved in lowering stress, improving mood and ensuring that the metabolism works, or functions effectively. A lack of sleep negatively affects the body in many physical ways, not to mention cognitive and emotional ways too. A night-time dose of 8-9 hours is ideal, especially in the days leading up to a race.
The role of protein and fat for fuelling and recovery…
An athlete can meet protein requirements, and boost general nutrient intake by following a diet that is rich in vegetables, fresh fruits, seeds, nuts and wholegrains. This can be balanced with consumption of meat, fish and other animal produce, all of which is effective in reaching protein requirements. As long as the diet is adequately balanced with quality proteins from a variety of plant or animal food sources, amino acid requirements can be satisfied.
Endurance exercise also relies on protein as a fuel, and much more so than short-duration exercise such as sprinting or weight training, which relies on carbohydrate for fuel. Whilst glycogen (stored carbohydrate in muscle tissue), and blood glucose provide the preferred substrate for chemical energy that fuels muscle power, protein and fat also supply fuel for muscles during long duration exercise. Intensity largely determines the ratio of carbohydrate: fat: protein utilisation in the body, and it’s estimated that during prolonged exercise, such as triathlon, long-distance running or cycling, the energy contribution from protein is between 2-8%, and possibly higher in states of glycogen depletion. It is vital to avoid excessive protein breakdown during exercise, for the simple reason that you want to preserve precious lean tissue, as well as preserve the integrity and strength of the immune system. One way to prevent the breakdown of muscle protein for fuel is to provide adequate carbohydrate. However consistent research has, demonstrated that protein ingestion during exercise will increase protein oxidation, potentially sparing blood glucose and/or muscle glycogen, as well as improving protein balance, by stimulating whole body protein synthesis. To summarise here, carbohydrate and protein ingestion seems to increase the total fuel available to the working muscles, beyond which is attainable with only carbohydrate. So, look out for sports drinks that contain carbohydrate, electrolytes AND amino acids. The growing body of evidence certainly seems to support the addition of protein to carbohydrate-electrolyte sports beverages used during endurance exercise as well as for recovery.
As previously mentioned, the estimated daily protein requirements of athletes are 1.2-1.7g per kg body weight. This is easy to achieve (practically speaking), by consuming quality proteins at each meal or snack. Foods such as fresh fish, organic eggs, or lean and healthy meat provide plenty of protein for carnivores. For vegetarians and vegans, consuming plenty of raw green vegetables, shelled hempseeds, fresh fruits, beans, seeds (especially sprouted), nuts, and wholegrains such as quinoa, buckwheat, rice, barley and oats, supplies a superb selection of proteins, as well as an abundance of antioxidants, essential fats, fibre and minerals. Post-workout smoothies and shakes, can be made with fresh fruits, raw leafy greens & vegetables such as cucumber and celery, with added high-protein seeds such as shelled hempseeds, flaxseeds or sunflower seeds. Liquid meals such as these are highly suitable post workout, being high in nutrition, easily digested and highly alkalising. Their net alkaline-enhancing effects make them perfect recovery nutrition for the athlete, who is naturally in an acidic state post-exercise. They are best taken within the first 30-45 minutes of recovery.
Dietary essential fats
Certain fats cannot be manufactured by the body, and must be sought from the diet. Commonly called “essential fats” (EFAs), these play important roles in immune function, cardiovascular function and fat metabolism. These fats help to build flexible cell membranes, important for oxygen delivery to the periphery of the body, and helping to improve aerobic fitness and VO2 Max. Many EFAs have anti-inflammatory properties too, crucial to the athlete for tissue repair and fast recovery. Oily fish and raw seeds are good examples of EFAs, emphasising the point that you do not necessarily have to add oils to the diet to obtain required amounts of essential, natural fats.
Five foods to aid sleep
Eggs – Eggs are particularly plentiful in the essential amino acid tryptophan, particularly the whites. Tryptophan functions as a precursor to the sleep-inducing neurotransmitters serotonin and melatonin, helping to promote rest and relaxation.
Potato/sweet potato – Potatoes are rich in carbohydrates. Eating carbohydrates with tryptophan-rich foods such as meat and eggs, increases the amount of tryptophan available to the brain, helping to manufacture more serotonin and melatonin.
Milk – Milk is another good source of the amino acid tryptophan, helping to increase brain levels of serotonin. Remember, serotonin slows down nerve traffic to the brain, calming brain activity and allowing for more restful sleep.
Banana – Bananas contain both carbohydrate and tryptophan. When you pair tryptophan-containing foods with carbohydrates, a combined chemistry occurs which calms the brain and allows for better sleep.
Cherries – Evidence shows that cherries (particularly Montmorency cherries) contain a significant amount of the hormone melatonin, enough to have a positive effect on sleep. Cherry juice has also been shown to enhance muscle recovery in athletes.
Food for Sport – Part 1