people assume that the human body operates like a machine and therefore
in order to work, it needs to be fueled like a machine. Eating before
exercise seems to make sense. But does it really?
you'll soon realize, the idea that pre-exercise meals provide the
muscle with instant energy is literally wrong, often misleading
and counter effective. In order to provide the muscle with nutrients
and energy, food must be first fully digested.
digestion food is broken down into smaller compounds, yielding molecules
of amino acids, fatty acids and glucose which are transferred
to the body's tissues through the circulatory system. The digestion
elimination process, that occurs in the stomach, intestines, liver
and kidneys, respectively, requires substantial amounts of energy.
During digestion, blood flow shifts from the brain and muscles to
the inside organs (responsible for digestion and elimination). That
shift in the blood flow profoundly affects the brain and muscle
tissues, lowing their capacity to perform and resist fatigue.
question remains: "What about meals that require almost no
digestion?" such as those made from fast assimilating nutrients.
(Note that fat is a slow digested and assimilated nutrient compared
to protein and carbs.)
a pre-exercise meal made from a blend of fast releasing proteins
and carbs (such as whey and sugar), looks initially quite appealing.
In theory such meals would nourish the muscle tissues with amino
acids and glucose to inhibit muscle breakdown, while providing instant
energy. It all makes sense, but even so, in real life, things often
work differently than in theory.
studies demonstrated that eating fast releasing foods before or
during exercise could be counter effective, to say the least. Investigators
in the school of sport and exercise science, University of Birmingham,
Edgbastion, England found that ingestion of carbs before exercise
adversely elevated plasma cortisol levels.
enough, there was a significant reduction in post exercise cortisol
when carbs were not ingested before exercise. Furthermore, there
was a faster shift from carb to fat fueling during exercise, when
a pre-exercise meal was not applied. As for protein, what failed
to reach mainstream nutrition knowledge is the already established
fact that protein rich foods raise cortisol levels if applied incorrectly.
at the University of Lubeck, in Germany, found that oral administration
of fast releasing protein foods such as hydrolyzed (pre-digested)
proteins, have an even more profound cortisol elevating effect,
compared to whole protein foods. Note that chronic elevated cortisol
has been associated with muscle wasting and fat gain (in particular
summary, pre-exercise meals may rob the brain and muscle of energy
(due to digestion). Eliminating the digestion effect of pre-exercise
meals may only make things worse. Eating meals made from fast releasing
proteins and cabs, before exercise, can cause a profound cortisol
elevating effect during and after exercise. This may severely compromise
ones ability to build muscle and burn fat.
conclusion, DO NOT EAT before exercise, instead eat right after
exercise. Ironically, the same meal that would be counter-effective
before exercise can be most effective and beneficial when applied
studies have demonstrated the critical positive effects of post-exercise
recovery meals on total muscle recuperation (i.e. replenishment
of energy reserves and increased protein synthesis). Recent studies
at the University of Texas Medical Branch, in Galveston, TX, revealed
that applying fast releasing proteins and carbs after exercise had
substantial anabolic effect on stimulating net muscle protein synthesis,
even in cases of elevated cortisol.
we are not preprogrammed to be fueled like machines. Our biological
machine is based on survival mechanisms that when triggered, increase
our capacity to utilize fuel, generate energy and better survive.
We trigger these mechanisms, when we follow cycles that rotate between
undereating while in an action followed by eating while in rest.
For the human body, timing affects everything. "It is when
you eat that makes what you eat matter."
to Apply Pre-Exercise Meals
can successfully apply pre-exercise meals without the typical adverse
effects (increased metabolic stress and elevated cortisol) by incorporating
the following tips: Such meals should consist of small amount of
protein or carbs coming from easy to digest, light fresh food sources
such as poached eggs yogurt or whey protein (up to 20g) or low glycemic
fruits (apples, berries, and papaya), one fruit or one bowl of fruit
per meal. (You should separate between protein meals and fruit meals.)
protein meals should have a higher ratio of protein/carbs or fat
than post-exercise recovery meals, to minimize insulin spike and
reduce digestion time before exercise, respectively. Pre-exercise
protein meals, to be fully digested, should be consumed up to a
couple of hours before exercise.
very small amount of fruits (1/2 of a bowl) or up to 10g of whey
protein could be applied up to one hour before exercise. Note that
the best time for energy loading isn't before exercise but in the
first 30 minutes after exercise. Replenishment of energy reserves
in the muscle reaches a peak potential via your post-exercise recovery
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