I chose the topic of preworkout nutrition for one reason: because current recommendations tell us to do the opposite of how the body acts physiologically.
The wrong pre-and intra-training nutrition can actually limit muscle’s access to an abundance of energy stored specifcally for high-intensity, high-strength, high-endurance training.
When we use the typical pre-workout formulations (high-carbohydrate or highprotein or both), we actually derail skeletal muscle from being able to access the large amount of energy stored immediately in the vicinity of where work is happening—in the muscle itself. With their capacity to store carbs in the form of glycogen and fatty acids in the form of triglycerides, muscles carry around their own supply of highly available, highimpact fuel.
The physiology behind accessing these energy stores is relatively simple and is based on the body’s acute and rapid stress response to training, which will be highest in a low-insulin level environment—whether you achieve that through fasting, waiting two hours or more after a meal, or being on a ketogenic diet. In this environment, without elevated insulin levels, all of the important stress hormones increase rapidly: glucagon, cortisol, and adrenalin/noradrenalin.
At first thought this seems like something we’d want to avoid— but, in fact, this combination is ideal. In the absence of elevated insulin levels and blood sugar, each of these hormones has a specific effect to help us access the high-impact, immediately available energy stored all over the body.
Glucagon stimulates the breakdown of liver glycogen to be released as blood glucose for peripheral tissue and the nervous system, as the muscles of the body cannot release their glycogen stores into the blood stream (because skeletal muscle lacks glucose-6-phosphatase, which is responsible for the final step of releasing glucose back into the blood stream during glycogen breakdown in the liver).
Cortisol helps to stimulate the breakdown of glycogen and triglycerides into glucose and fatty acids—again, providing energy to the body derived from internal energy stores.
Adrenaline is necessary to allow muscle tissue to access internal glycogen stores, and forces fat cells of the body to release fatty acids for energy.
This all happens in the absence of elevated insulin levels. The body still releases these hormones if insulin levels are higher, but they don’t do the same things. Glucagon will shift function and attempt to produce glucose from amino acids; cortisol can no longer cause fat cells to release fat, and instead, may cause pre-adipocytes (cells not yet capable of storing fat) to turn into fully functional adipocytes (which are capable of storing fat). Adrenaline takes longer to release, does not release to peak levels, and muscles don’t respond as strongly—and neither do fat cells.
In addition to these hormonal enhancements, keeping insulin levels low allows the liver to easily produce ketones, which act as high-efficiency fuel for the heart and diaphragm. Research shows that elevated ketone levels provide increased cardiovascular endurance during exercise. You can train harder and with higher volume. Raise insulin levels before training, however, and this effect disappears, too.
It’s very simple: If you don’t eat carbs for at least two hours before training—even heavy training—you’ll be stronger, exhaust glycogen levels, and mobilize body fat. You won’t just burn fat, you’ll lose body fat.
What can you take pre-training? The list is, at the moment, a short one. The general rule to ensure the above positive effects involves coconut or medium chain triglyceride (MCT) oil and possibly an amino acid supplement or protein powder. The ratio of grams of fat to grams of protein (or amino acids) is roughly 1:1 for these benefits; so 12 grams of MCT oil (1 tbsp) with 12 grams of protein. If you choose to use casein protein, you can up the ratio slightly to 2:3. This would be 12 grams of protein and 18 grams of casein. These combinations will keep you in the perfect hormonal environment to crush your workout drinking only water.
And let’s not forget about caffeine. In the absence of insulin, caffeine enhances all of the above effects, including raising cortisol levels during training. This may seem like something to avoid, but recent research demonstrates that the overall effectiveness of your training to cause performance gains most directly correlates with maximum cortisol levels during training. Most people can handle up to 800 milligrams of caffeine in a sitting, although I normally recommend a maximum of 400 milligrams (equivalent to two standard low-carb energy drinks). This pre-workout caffeine can also help restore intramuscular glycogen levels faster during post-workout feedings.
The real refueling comes at the end of the workout, when we store energy for the next day’s training; and without already elevated insulin levels, the body will replenish glycogen stores more rapidly.
Using this biological hack— no carbs before or during a workout, then superloading with carbs after—is one of the main principles of carb back-loading, which allows for body-fat loss while simultaneously building muscle. But postworkout nutrition is a topic for another article. - FLEX