Optimal Sports Nutrition for Endurance Athletes
Top 10 Tips for Peak Performance
By Kim Mueller, MS, RD
Are you looking for that “something” to help take your health and athletic performance to the next? Below, I provide you with latest in nutrition & exercise science to help optimize health and achieve peak run performance.
#10 IMPLEMENT CARBO-LOADING PROTOCOLS BEFORE LONG RACES
Carbo-loading protocols are appropriate when gearing up for races lasting 2+ hours and entail that a high carbohydrate training diet (55-60% of daily intake) is coordinated with a taper in training volume about 2-3 weeks out from race day and then increasing carbohydrate concentration by 25% while maintaining calorie balance the final three days leading up to race day. Popular carbo-loading menu items include pasta, potato, bagels, cereal, energy bars, fruit juice, bananas, rice, pretzels, and low-fat yogurt. By following carbo-loading protocols, muscle glycogen stores will increase 30-40% lowering the likelihood of hitting the wall mid-race.
#9 PRACTICE FUELING BEFORE RACING
Regardless of race distance or carbo-loading protocols, a pre-race meal is essential to protect against low blood sugars and mental drain known as ‘bonking’, especially when coming off a fasting state where fueling has not occurred over the previous 4 hours. The purpose of a pre-race meal is to restock the 100 grams of carbohydrate (400 calories) stored within the liver, helping to elevate blood sugars and improve energy levels prior to race start. Contrary to the high fiber recommendations that are provided from all corners of the health spectrum, fiber should be limited to no more than 10 grams on race morning as fiber takes longer to clear the gut and can leave your stomach feeling heavy if large amounts are consumed pre-race. Stick to lower-fiber, ‘gut-friendly’ pre-race options such as plain toast, bananas, rice or corn based cereal, pasta, and potato. To help mute hunger and stabilize blood sugars, inclusion of up to 25 grams of protein (e.g., 1/2 cup of scrambled eggs with toast) and up to 20 grams of fat (e.g., 2 Tbsp nut butter) is encouraged. Overall, aim at consuming 400-600 carbohydrate focused calories in the two hours leading up to race start as means to optimize blood sugars and protect against early onset of muscle fatigue.
#8 INCLUDE SALT ON RACE MORNING
Salt loading is a relatively new concept, but over the past five years, there have been a handful of studies producing promising results for the endurance athlete with regards to both performance and protection against hyponatremia. One study published just last year demonstrated that ingestion of 25 ounces of concentrated sodium beverage (2.8 grams) in the 105 minutes leading up to a run at 70% of VO2max helped increase blood volume, allowing the runners to maintain a lower core body temperature and a lower level of perceived effort. Similar results with the addition of increased exercise capacity have been demonstrated in female cyclists consuming 20 ounces of a concentrated sodium beverage (2.3 grams) in the 105 minutes leading up to a submaximal cycling effort in warm conditions. It is important to note that athletes are naturally exposed to sodium-rich foods (e.g., pretzels, bagels, tomato sauces, chips, sports drinks) and may not need to add extra salt to their normal pre-race routine. Runners with pre-existing elevated blood pressure should check with their physician before practicing salt loading.
#7 LEARN YOUR SWEAT RATE
Because dehydration ranks among the most common nutritional causes of performance decline in athletes, an understanding of sweat rate is of paramount importance when developing a race day nutrition plan. Determination of sweat rate is actually quite easy but it entails that a log be kept, monitoring the following items:
* Pre-workout naked weight Post-workout naked weight Total duration of workout Workout intensity Weather conditions
* Volume of fluid ingested during workout
To determine hourly fluid needs, subtract post workout weight from pre-workout weight and multiply by 15.2 ounces. Add this number to volume of fluid ingested during the workout to determine total fluid needs. Divide total fluid needs by total duration of workout to determine hourly fluid replacement needs. Note that as the heat index rises and/or the intensity of the workout increases, so does sweat rate. For optimal uptake of fluid and muscle hydration, 150-250 mg of sodium should be consumed per 1/2 – 3/4 lb weight loss. For reference, the average athlete requires 1/2 – 1 liter of water and 200-1,000 mg of sodium each hour during training or racing.
#6 BE AWARE OF YOUR BODY’S ABILITY TO ABSORB FLUIDS
Once sweat rate is determined, at the other end of the spectrum is determination of actual uptake rate (how much can you absorb), which research suggests falls just over a liter per hour (1.2 liters/hour) for most athletes. Monitoring the amount of fluids voided (how many times you pee during your run) as well as the color of urine can be helpful in determining how efficiently fluids are being absorbed. A sensation to void is healthy, but voiding multiple times in an hour is not. Urine that runs pale yellow is healthy but a clear color generally indicates fluids are not being absorbed. The risk that is run from overdrinking is hyponatremia (low blood sodium) that is driven by exertion-based losses of sodium in sweat as well as a dilution effect with excess fluids. Common symptoms associated with hyponatremia include a sloshy gut, bloating, headaches, clear urine, weight gain, and vomiting. If symptoms arise, it is important to taper back or stop fluid intake and in warm conditions, reduce effort (slow down) to slow exertion-based losses of sodium while implementing sodium-rich foods (e.g., pretzels, salt packs, etc.)
#5 USE MULTIPLE CARBOHYDRATE SOURCES DURING TRAINING AND RACING
Most studies indicate the maximal uptake simple sugars (e.g., glucose, fructose, sucrose) to be 1 gram per minute (60 grams per hour). However, new research reveals that carbohydrate uptake increases as high as 1.7 grams per minute (~100 grams per hour) when a combination or blend of two or more types of simple sugars and a complex carbohydrate (e.g., maltodextrin) are used, thereby having a positive impact on endurance performance, especially for ultra-marathoners engaging in back-to-back long run efforts or athletes working out twice a day. An improved carbohydrate uptake rate also means less depleted muscles at the end of the day, thereby helping to quicken recovery times post-effort.
#4 ADD PROTEIN FOR THE LONG HAUL
Inclusion of up to 6 grams of protein during training or racing lasting greater than three hours may help enhance endurance performance by sparing muscle glycogen as well as increasing fluid uptake. One study demonstrated nearly a 25% increase in cycling endurance when an hourly rate of 6 grams of protein was consumed in a 7.75% carbohydrate solution. Another study discovered that athletes utilizing protein during training had 20% more endurance during a 2nd planned workout during the day. Protein may also help enhance fluid uptake and provides some satiation for longer efforts. Be careful about overdoing protein, however, as large amounts slow gastric emptying and can precipitate a ‘backlog’ of nutrients of gut and consequent stomach distress and muscle fatigue/cramping.
#3: GO LONGER WITH LESS EFFORT WITH CAFFEINE
Coffee has been a long-standing habit for many athletes with some saying it helps them ‘clean-out’ their system before racing and others using a cup of ‘joe’ as means to enhance performance, which is warranted at a level of 4.5 mg of caffeine per pound of body weight taken immediately prior to racing as this dose has been shown to significantly extend endurance. More recently, however, the benefits of caffeine use during endurance activity have been evaluated. Researchers from Georgia have recently discovered that caffeine intake during prolonged exercise helps maintain blood glucose concentration and reduce strength loss through its effects on the active musculature and nervous system that reduce fatigue and perceptions of effort, discomfort, and pain. Study participants were given a total of 2.4 milligrams of caffeine per pound of body weight split up in dosing prior to and during their sub-maximal 2.25 hour effort to yield these positive results. Popular among endurance athletes are energy gels, which often are caffeinated at a dose of 25-50 mg pack. It is important to experiment with personal tolerance to caffeine as some athletes do not respond favorably to caffeine with symptoms such as a racing heart beat, muscle twitching, stomach distress, and anxiety serving as reason for avoidance.
#2 FOCUS ON LOW GLYCEMIC CARBOHYDRATES BETWEEN WORKOUTS
Consuming carbohydrates of any glycemic value will help encourage glycogen resynthesis and muscle recovery but low glycemic foods may be optimal for performance when back-to-back workouts are planned (e.g., double long runs for ultra-runners) as recent research has demonstrated a more efficient rate of fatty acid oxidation and a longer run to exhaustion when low glycemic carbohydrates are the focus of recovery between endurance trials. Additional research has shown low-fat chocolate milk, which yields a low glycemic response, to rank superior to higher glycemic alternatives (Gatorade and Endurox sports drinks) with respect to time to exhaustion and total work when consumed between two exhausting exercise bouts. For information on glycemic index, visit www.glycemicindex.com .
#1: FILL YOUR MEAL PLATE WITH FOODS THAT REDUCE INFLAMMATION
Researchers in the area of natural anti-inflammatories have a lot to smile about as there are several foods that present promise in this regard. One study by the Agricultural Research Services discovered that consumption of 45 fresh Bing cherries daily for one month helped lower three telltale indicators of inflammation-nitric oxide, C-reactive protein, and a marker for T-cell activation, by 18-25%. A similar study conducted by Muraleedharan Nair, PhD, and chemistry professor from Michigan State has shown in lab experiments that tart-cherry extract can stop the formation of some inflammatory agents ten times better than aspirin and similar benefits have also been demonstrated in sweet cherries, blackberries, strawberries, and raspberries. Cherries contain a nice cocktail of antioxidants, including quercetin, which received rave reviews by scientists presenting at this year’s American College of Sports Medicine for its anti-inflammatory qualities as well as potential to improve VO2max in endurance athletes. In general, fruits and vegetables, especially those with deep color hues, contain a plethora of phytonutrients shown to provide anti-inflammatory benefit. To help combat inflammation, athletes should focus on filling 50% of each meal plate with fruits and vegetables.