As a bootcamp instructor, I see athletic performance almost daily. I run drills in such a way that I know my bootcampers will be challenged, but ultimately they will be able to push past the uncomfortable physical barriers and improve their stamina. This part doesn’t come without some pain…during and after the session, but by fueling the body properly, this pain can be dramatically reduced and results can be greatly enhanced.
Can I just say that the Standard American Diet (We call it SAD for appropriate reasons) is in no way optimal for performance and recovery. If you push your body hard and expect great results, but you do not give the body the proper tools it needs to build and repair, it will exhaust its reserves and start to breakdown. This is why nutrition and physical fitness go hand-in-hand. Some people believe that if they exercise, they don’t need to take proper care with their diet, but actually, the complete opposite is true….YOU NEED IT MORE THAN EVER!
It’s like asking contractors to build you this huge Castle, but only giving them weak crumbly stones and only a couple of the tools they really need. Your body is similar. If you fuel it with processed foods rather than lots of fresh produce (including lots of veggies), adequate protein, and EFAs, then you set the body up to break down. If you’re truly committed to reaching your fitness goals, don’t short change yourself. Lay down the foundation for a strong, beautiful, and healthy body.
I came across an interesting article in the latest USARS magazine. It talks about optimal athletic performance and keeping up energy levels. It was reprinted from the US Olympic Nutrition for Athletes Guidelines. Remember, YOU ARE WHAT YOU EAT!NEVER
GET
HUNGRY,
NEVER
GET
THIRSTY:A Drug-Free Nutritional
Strategy for Optimizing
Athletic Performance
by Dan Benardot, Ph.D., DHC, RD, FACSM
Exercise has two
effects on nutrient
requirements.
It results in an increase in
the rate of energy usage
and, because of the greater
heat production associated
with higher levels of energy
metabolism, an increase in
the rate of water lost as sweat. It should be widely understood
that athletes need to increase energy substrate and
fluid consumption to meet this additional nutritional
burden, yet nutritional surveys suggest that athletes don’t
eat enough and don’t drink enough.1,2,3 Moreover, it appears
that energy consumption is not well timed, which negatively
impacts both body composition and performance.4,5,6
The outcome of this widespread athletic malnutrition is all
too well understood: An excessive reliance on supplements
and ergogenic aids to overcome the deficits created by
inadequate energy and fluid consumption. It is likely that
athletes who pay attention to food and drink intake will
do more to achieve at their conditioned capacity than
any other action they can take. Focusing on food and
drink is a less expensive, more dependable, and a safer
strategy for improving athletic performance than relying
on supplements and ergogenic aids, which may have
indefinite content and unpredictable quality.
ENERGY INTAKE
Much of the discussion on energy intake focuses on the
optimal distribution of the energy substrates: carbohydrate,
protein, and fat. (Although there is no question that focusing
on a diet high in complex carbohydrates, moderate in
protein, and relatively low in fat is performance enhancing.)
But this discussion has little meaning in the face of energy
intake inadequacy. Put simply, it doesn’t matter if you put
high-octane fuel in the system if there isn’t enough fuel
to get you where you want to go. Weight and lean mass
stability are the best indicator that energy intake matches
need. A failure to consume sufficient energy leads to either
a reduction in weight or a reduction in lean mass (or both),
as the body tries to compensate for this deficiency. For
most athletes, a lower relative lean mass and higher relative
fat mass is not desirable and is a physiological marker
associated with decreased performance. In what must be
considered a terribly wrong reaction to this relatively higher
fat mass, athletes commonly reduce energy intake still
further to reduce the fat mass. The impact of this constant
ratcheting down of energy intake is weight loss with a
greater loss of lean mass than fat mass, with fat constituting
an ever-higher proportion of body weight.7,8
It is possible that this cycle of lowering energy intake to
adapt to a constantly rising relative fat mass is predictive
of the eating disorders seen too often in athletes where
‘appearance’ is a factor in a sport’s subjective scoring.9 To
emphasize this point, it should be noted that anorexia
nervosa victims at death have a terrible loss of weight, a
terrible loss of lean mass (the weight of the heart is typically
50% of normal), but a relatively high body fat percent.
Severely deficient caloric intakes, therefore, lead to a
greater cachexia of lean mass than fat mass.10 The concept
that a significant reduction in calories (i.e., ‘dieting’)
results in an improved body profile and body composition
simply does not stand up to scrutiny. While a short-term
subtle lowering of body weight may be temporarily associated
with an enhanced performance, the long-term effects
of such low-calorie ‘diets’ is to lower the intake of needed
nutrients (a problem that can manifest itself in disease
frequency and increased risk for low bone density) and to
regain the weight, which is made up of less lean and more
fat. To make matters worse, the lowering of lean mass
makes eating normally without weight gain more difficult.
A micro-economic view of the energy balance issue may
shed some light on how athletes should eat to achieve an
optimal body composition that enhances performance. A
study of 4 groups of national-level female athletes (rhythmic
gymnasts, artistic gymnasts, middle-distance runners, and
long-distance runners) found that those who deviated most
widely from perfect energy balance highest body fat levels, regardless of whether the energy
deviations represented surpluses or deficits.11 This strongly
suggests that the common eating pattern for athletes,
which is typified by infrequent meals with a heavy emphasis
on a large end-of-day meal, is not useful for meeting
athletic goals because it is guaranteed to create large
energy deficits during the day. While this energy deficit
may be made up for at the end of the day to put an athlete
in an ‘energy balanced’ state, this type of eating pattern
is typified by weight stability but higher than desirable
body fat levels.
Understanding that blood sugar fluxes every three hours
(after a meal, it rises, levels off, and drops in three hours),
the reason for the higher body fat level becomes clear.
With delayed eating, blood sugar drops and the amino acid
alanine is recruited from muscle tissue to be converted
to glucose by the liver. While this stabilizes blood sugar,
it does so at the cost of the muscle mass. In addition,
both low blood sugar and large meals are associated with
hyperinsulinemia, which encourages the manufacture of
fat. So, delayed eating followed by an excessively large
meal, which is typical of the athletic eating paradigm, is
an ideal way to lower muscle mass and increase fat mass…
not what athletes want to do. A number of studies that
have assessed eating frequency have come to the same
conclusion: the more frequent the eating pattern, the
lower the body fat and the higher the muscle mass.12,13,14,15
Frequent eating reduces the size of within-day energy
deficits and surpluses, and helps to stabilize blood sugar.
Athletes concerned about weight have, for a long time,
learned to cope with the feeling of low blood sugar by
consuming a diet product (diet colas are popular). While
these diet products do nothing to resolve the very real
physiological need for energy to maintain an adequate
blood sugar, they do provide a central nervous system
stimulant (usually caffeine) that masks the sensation of
hunger. However, since the status of the blood sugar is
maintained at a low level through this strategy, the outcome
will inevitably be less muscle and more fat. It is clear from
these studies that the only appropriate strategy of weight
loss is a subtle energy deficit that results in only a slight
deviation from a within-day energy-balanced state.
What are athletes to do? Never get hungry. This is not easy
on a typical 3-meal-a-day eating pattern, which provides
for a refueling stop every 5 to 6 hours, and it is less easy
on typical athlete eating patterns which heavily backload
intake. Since blood sugar is known to rise and fall in 3
hour units, it makes sense to have planned snacks. If
you’re weight stable, the best way to initiate this process
so you don’t eat too much is to eat a bit less at breakfast,
and eat the remainder at mid-morning, and do the same
for lunch and dinner. Total caloric intake will remain the
same, but the athlete will avoid sharp energy deficits and
surpluses during the day. Besides the improved nutrient
intake, and better body composition associated with this
type of eating pattern, athletes can also expect improved
mental acuity and enhanced athletic performance.
FLUID INTAKE
Perhaps the single most important factor associated with
sustaining a high level of athletic performance is maintenance
of blood volume during exercise. Despite this, studies
have demonstrated that, even in the presence of available
fluids, athletes experience a degree of voluntary dehydration
that lowers blood volume and negatively impacts
performance.16 Given the tremendous amount of heat that
must be dissipated during exercise through sweat evaporation,
athletes have no reasonable alternative for sustaining
exercise performance than to pursue strategies that
will sustain the hydration state. Failing this will result in,
at a minimum, premature fatigue and may also lead to
potentially life-threatening heat stroke.
Temperature regulation represents the balance between
heat produced or received (heat-in), and heat removed
(heat-out). When the body’s temperature regulation system
is working correctly, heat-in and heat-out are in perfect
balance and body temperature is maintained.17 The two
primary systems for dissipating or losing heat while at rest
are to move more blood to the skin to allow heat dissipation
through radiation and to increase the rate of sweat
production. These two systems account for about 85% of
the heat lost when a person is at rest, but during exercise
virtually all heat loss occurs from the evaporation of sweat.
Working muscles demand more blood flow to deliver
nutrients and to remove the metabolic by-products of
burned fuel, but at the very same time there is a need to
shift blood away from the muscles and toward the skin
to increase the sweat rate. With low blood volume, one
or both of these systems fail, with a resultant decrease in
athletic performance.
Heavy exercise can produce heat that is 20 times higher
that the heat produced at rest. Without an efficient means
to remove this excess heat, body temperature will rise
quickly. (The upper limit for human survival is about
110° F, or only 11.5° F higher than normal body temperature.)
With the potential for body temperature to rise at
the rate of about 1°F every 5 minutes, it is conceivable
that underhydrated athletes could be at heat stroke risk
only 55 minutes after the initiation of exercise.18
Athletes working hard for 30 minutes would create 450
kcal of excess heat that would need to be dissipated to
maintain body temperature. Since 1 ml of sweat can
dissipate approximately 0.5 calories, athletes would lose
about 900 ml (almost 1 liter) of sweat. In one hour of
high intensity activity, approximately 1.8 liters of water
would be lost. On sunny and hot days when the heat of
the sun is added to the heat produced from muscular
work, athletes would need to produce even more sweat
to remove more heat. Sweat doesn’t evaporate off the
skin as easily when it is humid, so still more sweat must
be produced in hot and humid weather. Well-trained
athletes exercising in a hot and humid environment may
lose over 3 liters of fluid per hour.19
No level of low body water is acceptable for achieving
optimal athletic performance and endurance, so athletes
should have a strategy for maintaining optimal body water
during exercise. The problem is that athletes often rely on
thirst as the marker of when to drink. Since the thirst sensation
only occurs after a loss of 1 to 2 liters of body water,
relying on thirst is an inappropriate indicator of when to
drink.20 Instead, the athlete should strategize on how to
V O
never get thirsty. Ideally, this strategy should involve helping
athletes determine how much fluid is lost during typical
bouts of physical activity, and developing a fixed fluid
consumption schedule from that information (typically 3 to
8 ounces every 10 to 15 minutes of a sodium-containing
6–7% carbohydrate solution.)
SUMMARY
Both hunger and thirst are emergency sensations marking
the onset of performance-reducing problems. As such, they
should be avoided through a planned eating and drinking
timetable that is integral to the athletes’ training schedule
and lifestyle. Perhaps no other two factors have the potential
for making such an enormous positive impact on
health and performance. Put simply, athletes interested in
performing up to their conditioned abilities and skill levels
should never get hungry and never get thirsty.
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