The Paleo Diet for Athletes (9 page)

But the research doesn’t always support these explanations. For example, in the mid-1980s, 82 male runners were tested before and after a marathon for certain blood parameters considered to be likely causes of muscle cramps. Fifteen of the runners experienced cramps after 18 miles. There was no difference, either before or after the race, in blood levels of sodium, potassium, bicarbonate, hemoglobin, or hematocrit. There was also no difference in blood volume between the crampers and the noncrampers, nor were there significant differences in the way the two groups trained.

Note that we are talking about exercise-induced cramps here. In such cases of cramping, the knotted muscle is almost always one that is involved in movement in the sport. If depletion of electrolytes was a cause of cramping during exercise, why wouldn’t the entire body cramp up? Why just the working muscles? Electrolytes are lost throughout the body, not just in working muscles. We know that people who become clinically hyponatremic by losing a great deal of body salts (not exercise-induced) cramp in
all
of their muscles. It’s generalized, not localized.

It should also be pointed out that when someone cramps, the “fix” is not hurriedly drinking a solution of electrolytes, but rather stretching the offending muscle. For example, a runner with a calf cramp will stop and stretch the calf muscle by leaning against a wall or other object while dorsiflexing the ankle against resistance—the standard “runners stretch.”

In fact, what is known is that sweat, with regard to electrolytes, is hypotonic. That means the concentration of sodium, potassium, magnesium, chloride, and calcium is weaker than it is in the body. This indicates that more water is lost in the sweat than electrolytes. So if the body lost more of its stored water but not as much of its electrolytes, what would happen to electrolyte concentration in the body? The concentration would increase. So during exercise when you dehydrate and lose electrolytes, their concentration in the body is greater than it was before you started to exercise. The body functions based on concentrations, not on absolute amounts. That alone presents a great problem for the argument that the cause of cramping is the loss of electrolytes that must be replaced.

So if dehydration or electrolyte loss through sweat doesn’t cause cramping, what does? No one knows for sure, but theories are emerging. Some researchers blame poor posture or inefficient biomechanics. Poor movement patterns may cause a disturbance in the activity of the Golgi tendon organs—“strain gauges” built into the tendon to prevent muscle tears. When activated, these organs cause the threatened muscle to relax while stimulating the antagonistic muscle—the one that moves the joint in the opposite way—to fire. There may be some quirk of body mechanics that upsets a Golgi device and sets off the cramping pattern. If that is the cause, prevention may involve improving biomechanics and regularly stretching and strengthening muscles that seem to cramp, along with stretching and strengthening their antagonistic muscles.

Another theory is that cramps result from the burning of protein for fuel in the absence of readily available carbohydrate. In fact, one study supports such a notion: Muscle cramps occurred in exercising subjects who reached the highest levels of ammonia release, indicating that protein was being used to fuel the muscles during exercise. This suggests a need for greater carbohydrate stores before, and replacement of those stores during, intense and long-lasting exercise.

When you feel a cramp coming on, there are two ways to deal with it. One is to reduce your intensity and slow down—not a popular option in an important race. Another is to alternately stretch and relax the affected muscle group while continuing to move. This is difficult if not impossible to do in some sports, such as running, and with certain muscles.

There is a third option that some athletes swear by: pinching the upper lip. Who knows—it may work for you the next time a cramp strikes.

EATING DURING 12- TO 18-HOUR EVENTS

Events in this duration include the Ironman-distance triathlon, double-century bike ride, and ultra-marathons in such sports as running, mountain biking, cross-country skiing, swimming, and kayaking. The stresses placed on the athlete can be extreme, with fatigue, heat, humidity, hills, wind, and currents taking their toll and gradually reducing performance. Nutrition is critical for these events.

Much of what was said in the previous section remains true here. The caveats are that solid foods now become a necessity, and hunger may
well dictate what you decide to use for fuel. This might include bananas, cookies, jelly sandwiches, fruit juices, and soup. All of the foods selected should be toward the high end of the glycemic index. Otherwise, intake of carbohydrate, protein (especially branched-chain amino acids), and caffeine, as described above, may be continued.

EATING DURING EVENTS LONGER THAN 18 HOURS

These are the true “ultra” events of the world of endurance sports: the Race Across America (RAAM) and Paris-Brest-Paris bike races, double-Ironman-distance triathlon, Western States 100-mile run, and multiday bicycle racing tours such as the grueling Tour de France, the Vuelta a Espana, and the Giro d’Italia. It can be very difficult to take in adequate food and water, but for events done in daily stages, such as the Tour de France, daily nutritional intake between stages is often the difference between finishing and dropping out.

The longer the event, the more crucial it is that caloric needs be met by balancing nutrient intake with expenditure. Unsupported events require the athlete to carry nutrients or purchase them along the route, which makes planning all the more critical—the preferred sources must be light or generally available at convenience stores. Plan on taking in at least 6,000 calories daily—and that’s conservative. RAAM riders who spend at least 5 days riding across the United States, from the West to the East Coast, typically report 10,000-calorie days.

The longer the event, the lower the intensity, diminishing the relative amount of carbohydrate used as fuel. Whereas carbohydrate may account for 80 percent of the expended calories in events that last less than 90 minutes, it may contribute only about 50 percent of the total energy used in ultra-events. This means that the carbohydrate content of your fuel need not be as carbohydrate-rich as for shorter events. Conversely, protein intake becomes more important and should make
up 5 to 15 percent of your fuel, so your nutritional source should reflect this demand. Not getting enough protein may well result in muscle wasting. That’s not conducive to good performance.

Fat also becomes more important in events of this duration. You’ll burn a lot of it, so it’s okay to take in a considerable amount—a fifth to a third of your fuel source—during the activity. In fact, ultra-marathoners often report a craving for fat during their events. Fat tends to present fewer gut problems during exercise than carbohydrate does, but that doesn’t mean it won’t affect your stomach at all. Before the event, be sure to experiment to discover the mix and types of fuels that work best for you.

Nutritional Goals for 18+ Hour Events

Given the importance of refueling in events of this duration, it’s a good idea to closely examine all aspects of nutrition in great detail. Let’s start by considering the nutritional goals for the ultra-marathon athlete.

Replace all of the expended carbohydrate.
Even at relatively slow velocities, a considerable amount of dietary carbohydrate is needed to delay the onset of fatigue while maintaining power. Carbohydrate should be taken in from the outset of exercise, using predominantly high glycemic index sources. It’s generally best that the sports drinks you choose have greater maltodextrin or glucose sources than fructose.

What changes from the previous discussions, however, is that the demand for carbohydrate relative to time is reduced. You’ll be using less fuel per hour while burning fewer calories from carbohydrate sources and more from fat than for short events, so the total replacement of carbohydrate is not as difficult as in shorter, faster events.

Prevent excessive dehydration while avoiding hyponatremia.
Staying adequately hydrated for such events is critical. Once you are excessively dehydrated, it is difficult to get fluid levels back to normal. As always, use thirst as your guide to drinking. Hyponatremia is a threat to all athletes, including the faster ones, in events of this duration. The key, again, is drinking to satisfy thirst and not on a schedule. There will be a significant loss of body weight due to dehydration in each
day’s activity in multiday events even while you are drinking to thirst. During rest and recovery times fluids should be consumed as desired.

Prevent central nervous system fatigue.
Low levels of branched-chain amino acids in the blood during these long events can allow serotonin to enter the brain, causing the central nervous system to fatigue even though the other systems of the body are doing well. (See
“What Is Fatigue?”
)

Prevent muscle wasting.
It is not unusual for athletes in ultra-distance events, such as the Tour de France, to lose several pounds, mostly from muscle. A study of trekkers in the Andes found that those who supplemented their diet with branched-chain amino acids gained muscle mass over 21 days, while their placebo-supplemented companions who otherwise ate the same diet lost muscle. Without adequate protein intake, the trekkers’ bodies were “cannibalizing” themselves. This helps us understand why, after ultra-marathon events, athletes look so gaunt. To prevent muscle catabolism, it is critical that the athlete take in protein along with carbohydrate during the race.

Prevent hunger.
You will become quite hungry if you go 18 hours or longer with nothing more than sports drinks and gels. Foods including solid sources are a necessity, as they are more energy-dense than liquid sources. You’ll also find that after several hours, you become very tired of sweets and crave fat. Follow your desires and eat what sounds appealing, but consider these treats rather than main sources of fuel. The typical warnings still stand: Keep these foods low in fiber, and try them in workouts before using them in races.

Nutritional Guidelines for 18+ Hour Events

The guidelines for including fat and protein (primarily branched-chain amino acids) now shift toward fat and protein and slightly away from carbohydrate. Your 300 to 600 calories hourly from carbohydrate, fat, and protein should be broken down, respectively, as 60 to 70 percent, 20 to 30 percent, and 10 to 15 percent. This proportion may enhance performance and recovery, while helping to prevent the serotonin buildup
that can cause central nervous system fatigue and greater exertion.

Races of this distance often provide or allow support in the form of aid stations, feed zones, or even following support vehicles. This makes the replacement of huge energy needs throughout the event possible. For multiday events such as bicycle stage races, rest and recovery breaks are the times when the day’s caloric expenditures must be made up. During these times, which are essentially Stages IV and V of daily recovery, an assortment of foods such as potatoes, sweet potatoes, yams, vegetables, turkey sandwiches, fresh fruits, and soup will provide carbohydrate, fat, and protein.

CHAPTER 4

S
TAGES
III, IV,
AND
V: E
ATING
A
FTER
E
XERCISE

Immediately after a race or workout ends, it’s time to start focusing on recovery. This should be your highest priority. The higher your athletic goals, the more important quick recovery becomes. If you aspire to achieve at your peak levels, then both the quantity and quality of training are crucial for success. The sooner you can do another key workout, the faster you will get into race shape and the better your results will be.

If everything is done right nutritionally, both before and during the exercise session, then you’re well on your way to accomplishing this result. Following exercise, your objective must be to return your body to its preexercise levels of hydration, glycogen storage, and muscle protein status as quickly as possible. Diet is the critical component in this process.

There are three stages in this process: 30 minutes postexercise (Stage III); short-term postexercise (Stage IV), lasting as long as the exercise session; and long-term postexercise (Stage V), lasting until the next Stage I. Generally these stages will occur in sequential order from I through V. But on days when multiple workouts are done with only a few hours
between sessions, Stages III and IV may be completed followed by a return to Stage 1, repeating the entire process. Stage V would then be very late in the day. This is quite common for serious athletes who train and race at a high level. Stages III and IV may also be modified based on the total stress of the workout. Let’s examine the details of each stage of postexercise recovery.

STAGE III: EATING 30 MINUTES POSTEXERCISE

Following a highly stressful workout or race, this is the most critical phase. During the first 30 minutes after exercise stops, your body is better prepared to receive and store carbohydrate than at any other time during the day. If the preceding session was challenging, your body’s glycogen stores have been significantly diminished and there may be damage to muscles as well. Get nutrition right now, and you are well on your way to the next key workout. Blow it, and you’re certain to delay recovery.

Timing is a critical component for this stage. At no other time in the day is your body as receptive as it is now to macronutrient intake. Research shows that the restocking of the muscles’ carbohydrate stores is two to three times as rapid immediately after exercise as it is a few hours later. In the same way, other research reveals that the repair of muscles damaged during exercise is more effective if protein is consumed immediately after exercise. Don’t delay. Begin refueling as soon as possible after your cooldown.