Nutrition strategies

From the Fall 2010 issue of Coast&Kayak Magazine. Read the entire magazine online.

Whether training to race, or to just paddle longer, careful attention to your diet can vastly improve your recovery time

By Roy Stevenson

Sports nutrition has come a long way, and is easily one of the most researched disciplines in exercise science. Literally thousands of research papers have been written on recovery nutrition.

We need to pay attention to recovering properly from our kayak training simply because the human body is not designed for the extended, rigorous, high-intensity workouts that we put ourselves through. It’s a wonder we don’t break down more often than we do.

The benefits of recovering properly from these hard training efforts are clear. The kayaker who recovers quickly can train hard again with a shorter recovery time, add more quality training in his schedule, suffer fewer injuries and gain an enhanced immune system. All this translates into a fitter, faster and healthier paddler.

The strategies we use to speed up our post training recovery are rehydration, glycogen resynthesis and protein and antioxidant supplementation. These techniques replenish our muscle fuel supplies, hasten the repair of muscle damage and combat free radical formation in our cells.

But the devil is in the details. You can pop vitamin pills, drink protein powder shakes, guzzle sports drinks, and eat all the carbohydrates you can stomach, but if you don’t eat and drink the right kinds of food, drink and supplements at the right time, you’ll be wasting your time and money. It’s not just what you eat but when you eat it that counts in your recovery. Here’s how to use recovery nutrition to get the most out of yourself after your hard training and long kayaking efforts.

Post-training rehydration: replace water, electrolytes

Your first priority is to fully replace muscle and plasma fluid and electrolyte losses immediately after kayaking. Weigh yourself before and after your training effort and make sure you drink the lost weight back within an hour or two of finishing. In fact, aim to drink 125 percent of the weight you lost from sweating because you still continue to sweat while you are rehydrating.

Recent research shows that we absorb more fluid when electrolytes are added to water, thus achieving better restoration of body water. Sodium in particular helps retain water and stimulates thirst.

Use carbohydrates to replenish glycogen stores

Carbohydrates consumed immediately after and from two to five hours after exercise enhance muscle glycogen restoration. This is most effective if ingested from fluid, because fluid absorption is faster than digestion of solid foods. Edward Coyle, Ph.D., exercise physiologist at the University of Texas in Austin, says the first two hours after your workout are the most crucial for getting glycogen into your system.

“The muscles absorb glycogen like a sponge,” he says, but “four to six hours after training the absorption rate starts to decline.”

Choose carbohydrate-rich fluids to replace your water losses, electrolytes and muscle glycogen. Reading the labels of sports drinks is important because many of them are simply soft drinks in disguise, with excess amounts of sugar and caffeine. Select fruit juices or reputable sports drinks according to your preference – and there’s no rule that says you can’t drink both.

You’ll know you’re rehydrating adequately when you start urinating again, which can be several hours after training. Urine should be clear and pale. Despite the refreshing taste, beer (or any other alcohol) is counterproductive to good recovery because its diuretic effect prevents you from rehydrating properly at a critical time.

A carbohydrate/protein mix replenishes glycogen faster

Researchers have discovered that carbohydrate-rich fluids, when mixed with protein, have an important benefit. They’ve found that a mixture of protein and carbohydrate taken immediately after exercise tops up our glycogen and amino acid stores much faster than a carbohydrate solution alone.

The general consensus is that carbohydrate-protein mixes double the insulin response and increases the rate of glycogen synthesis by 30 percent. Since insulin is the hormone that takes up sugar and deposits it into our muscle cells, it follows that a solution that creates a high insulin response will build high intramuscular glycogen levels, and do this quickly.

How much protein is needed for this synergistic glycogen building effect? We recommend that athletes ingest 0.4 grams of protein per kilogram of body weight immediately after training and again two hours later.

The protein is best absorbed in the form of whey or casein powder. These powders come in several flavors and can be found in nutrition or sports nutrition stores.

There’s also been a big fuss lately about how low-fat chocolate milk is an ideal post exercise fluid for enhancing glycogen stores because of the good ratio of carbohydrates to protein. If you like chocolate milk, then by all means have at it!

As for the carbohydrates we should be ingesting after training, some carbohydrates cause rapid rises in blood sugar levels (high glycemic index), while others promote a slower release of sugars into the bloodstream (low glycemic index). We should aim to eat and drink high glycemic index foods immediately after training to boost our blood glucose levels quickly, thus causing a faster release of insulin, which in turn drives more glycogen into the muscle cells.

How much carbohydrate should we take in? The recommended dose is 0.5 to 0.75 grams of carbohydrate for every pound of body weight. And a second dose of high glycemic index carbohydrates is recommended from one to four hours post-exercise.

There’s an important dosage requirement for this carbohydrate/protein mix to be effective. The ratio of carbohydrate to protein is most effective at four to one. This new research on carbohydrate/protein synergy has great implications for athletes. You should be taking on board a mixture of protein and carbohydrates (preferably in fluid form) in a 4:1 ratio, immediately after training or extended kayaking efforts.

The kayaker’s need for protein

The paddler’s need for extra protein is well documented and we may even require more protein than bodybuilders relative to our body weight. After all, kayakers need to compensate for the physiological demands that paddling places on our bodies: increased breakdown of muscle contractile proteins, increased production of red blood cells, increased mitochondrial protein content, faster replacement of glycogen stores and increased oxidation and use of amino acids as fuel when muscle glycogen is low.

The role of vitamins and antioxidants in muscle repair

The downside to strenuous aerobic activity is the increased stress on our body’s cells caused by the huge amount of oxygen we process while training. This process, called oxidation, damages the muscle cell’s membrane and internal structure, impairing their function. The result: muscle soreness, inflammation and fatigue – all done by nasty little molecules called free radicals.

Vitamins assist in growth, tissue damage repair and disarming free radical damage from stressful environments such as pollution and extreme cold. A strong case can be presented in favor of antioxidant vitamins being taken to hasten recovery of free radical damage, damaged muscle and connective tissue, immune system suppression and oxidative stress caused by kayaking.

Antioxidants, produced naturally in the body, or obtained from our food, block most free radical reactions. Evidence exists that certain antioxidant supplements reduce free radical damage in athletes. One study found that five months of vitamin E supplementation in racing cyclists reduced markers of oxidative stress induced by extreme endurance exercise.

Some studies show that Vitamin E can reduce leakage of cell membranes to result in less creatine kinase (an inflammatory enzyme) and several other indicators of oxidative stress. Another study found that three grams a day of Vitamin C administered for two weeks before and two weeks after damaging eccentric exercise significantly reduced onset muscle soreness and pain in their subjects.

Monique Ryan, in her excellent book Sports Nutrition for Endurance Athletes, summarizes: “For endurance athletes they (supplements) are crucially important. Because of your training and stress it imposes on your body, you may need higher amounts of vitamins and minerals than sedentary people. And, as an athlete, you have a highly vested interest in keeping your immune system healthy so that illness does not put a halt to your training.”

She continues, “Vitamins and minerals are essential for metabolizing energy, building body tissue, maintaining fluid balance and carrying oxygen in the body. Vitamins and minerals also play a role in reducing the oxidative stress that is brought on by endurance training.”

Immune system recovery

Only one nutritional substance has been shown to enhance the immune system in athletes. That is drinking a carbohydrate solution during and after endurance exercise. Drinking one litre per hour of typical sports drinks has been shown to lower blood cortisol and epinephrine levels, reduce adverse changes in blood immune cells and lower anti-inflammatories such as cytokine.

Proteins also play an important role in helping our body fight off infection, especially in the two hours or so after exercise when we’re particularly susceptible to catching upper respiratory tract infections. As proteins make up the infection-fighting agents like macrophages, immunoglobins and white blood cells, ingesting proteins after strenuous exercise will in all probability help us fight any intruding infections and bacteria.

I’d suggest that you adopt a holistic approach when devising your nutritional recovery program, and attempt to use carbohydrate/protein sports drinks, fluids with adequate electrolytes, and antioxidant supplements as indicated. If you persist with this program you should find that your health is improved and your kayaking performance is significantly improved after a few months.

Roy Stevenson has a master’s degree in exercise physiology and coaching from Ohio University. He teaches exercise science at Seattle University in Washington State. As a freelance writer, Roy has over 200 articles on sports conditioning, running, triathlons, fitness and health published in over sixty regional, national and international magazines in the U.S.A, Canada, England, Scotland, Ireland, South Africa, Australia and New Zealand. To view more of Roy Stevenson’s articles go to www.roy-stevenson.com