Biohacking Carbs (Part 2)

In Part 1, I discussed biohacking carbs using light. Part 2 of my biohack is about manipulating the circadian rhythm using exercise.

Part 2: Using Exercise to Biohack Carbs

The key to this component of my biohack is to understand the circadian rhythm of 2 important hormones: glucagon and insulin. Additionally, it is important to also tie these hormones into leptin to get the bigger picture.

Insulin is a hormone released by the pancreas in response to consuming carbs. It’s role is to transport glucose from the blood to muscle and fat tissue as energy storage. Glucagon does the inverse; it mobilizes glucose from muscle and fat tissue into blood circulation to be delivered to where needed. A simple way to put it, is insulin is a glucose storage hormone, and glucagon is glucose burning hormone.

Eating food raises insulin, while fasting, sleeping and exercise decrease it. Once insulin is released, the body cannot burn fat until the insulin levels drop back down. Insulin sensitivity is associated with a relatively quick return to baseline post carbload. People who have good insulin sensitivity will be able to transition more quickly from fat storage to fat burning, while people with poor insulin sensitivity (diabetes) will not. Naturally, in healthy individuals, insulin sensitivity is highest in the morning and day, and lowest in the evening. Also, temperature has an effect on insulin sensitivity: higher in warm weather, lower in the cold. This means that if carbs are eaten during the day, blood sugar levels should return to baseline relatively quickly because muscle and fat tissue absorb them well. But carbs eaten in the evening will result in a longer duration of insulin secretion and a slower return to baseline blood sugar levels. If you have high blood sugar going into the evening, your ability to use leptin to burn fat in your sleep will be compromised (more on that later).

What happens when we exercise our muscles? We significantly increase insulin sensitivity in muscle tissue. Therefore, if we exercise in the latter half of the day, can we increase insulin sensitivity in the muscles, while insulin sensitivity is low in fat tissue? Yes. This is the concept of carb backloading by John Kiefer. Basically, you exercise an hour or so before dinner, and then load up on carbs. The best carbs to consume are ones that will spike your blood sugar very quickly, so simple sugars work much better than complex carbs with lots of fibre. The idea is that you are triggering a massive increase in glucose uptake to the muscles, without increasing any uptake to fat tissue. Basically in theory, your muscles are soaking up all that sugar via the action of insulin, and it's virtually impossible to gain fat. With the increase in insulin sensitivity following exercise, blood sugar levels should return to baseline relatively quickly, allowing for normal levels going into the evening, so you can burn fat in your sleep while your muscles are well fed.
 
Here is the complete biohack I tested last week:

1. Went tanning for 12 mins, and used UVA light for 4-5 hours
2. Exercised Back and Biceps at 3:30 PM
3. Consumed 150g of carbs for dinner
4. No blood sugar issues, no fat gain, and no other signs of inflammation that would normally occur when eating a massive amount of carbs in the evening, let alone winter

Blood Sugar:

It's important to know what your fasting blood sugar level is on average. Mine is usually somewhere between 4.0 and 4.5 mmol/l. My first meal of the day is always a high fat/moderate protein/low-no carb meal that has no effect on my blood sugar. This meal was eaten around noon. My workout went until just after 4:00 PM. I took my blood sugar immediately after the workout and it was 6.5 mmol/l. WOAH, what happened?! Am I a pre-diabetic? No. Exercise temporarily induces insulin resistance. Why? Because when you exercise, you are mobilizing glucose, not storing it. If insulin levels were high during exercise, you would experience hypoglycemia and probably pass out. So insulin is essentially shut off during high intense activity, and glucagon is upregulated in addition to growth hormone that actually increases your blood sugar which is burned off (oxidized). After finishing exercise, there is a delay period where glucagon and growth hormone slowly fall, and as this occurs, insulin sensitivity is actually enhanced, and your blood sugar should normalize within an hour. So I took a second reading around 5 PM, and sure enough, my levels dropped to 3.5 mmol/l, and I felt great, and ready for my feast!


I went into dinner with a low 3.5 mmol/l blood sugar level and pounded back 150g of carbs from a steak sandwich, sweet potato fries, and a DQ blizzard. YUM! I finished my last bite by 6 PM. By 8 PM I was ready to determine if this biohack was a success or a fail. For a more accurate result, I probably should have waited until 9 PM, because in a normal, healthy, insulin sensitive individual, it should take about 3-4 hours for blood sugar levels to return to baseline after a carbload. None the less, my glucose reading was 4.9 mmol/l. Not too shabby! I went to bed around 9:30, and my guess is by then, I was probably closer to 4.0 mmol/l.

My sleep was pretty good, but I definitely noticed I was radiating heat throughout the night! This can easily be explained by leptin entering the brain during sleep as the mitochondria uncouple from ATP production to burn off any excess calories I consumed as pure heat (hence why calories don't matter if you know how to maximize your leptin sensitivity). 

The next morning, I looked fuller in the mirror, but tighter. I stepped on the scale, and what do ya know? Down 1 lb! Success!