When you have gone down the health and fitness “rabbit hole” as far as I have, you start to learn that a lot of the general fitness advice said by many lazy fitness professionals is completely wrong. A common false statement I hear all the time is “You should really eat something before a workout in order to perform your best”. It is not only false, it is wrong. The result of eating right before a High Intensity Training (HIT) session workout, like a cardio kickboxing class, will most likely have you paying homage to the porcelain god! Don’t take this to the other extreme. For example, if you are planing on working out around 7pm, I don’t recommend you starve yourself the entire day, either.
So what should you be eating and when? Well, if you work out around 6pm an “ideal food” day would be:
- Eat breakfast
- Eat lunch
- Maybe a light afternoon snack around 3pm (if needed) such as some fruit or raw almonds.
- Workout at 6pm (3-hrs later),
- After workout – Eat a nice big healthy meal.
Other than a piece of fruit I would not recommend eat anything in the 3 hours preceding the class.
Why? Because your muscles, lungs, heart, and stomach all compete for your precious blood supply. You need blood to supply energy and oxygen to your muscles, lunges, heart, and brain while your stomach also needs energy and oxygen to digest the food you just ate. Something has to give. If the food is not able to digest because your muscle are taking more then their fair share of the blood supply, that food will just sit there and bounce around as you do jumping jacks. This is not how digestion is supposed to work, so the stomach will start to look for ways to get rid of said food, by any means necessary.
If you workout in the morning 6am or 9:30am (depending on what time you wake up), it is very possible to do these classes without eating, I do it all the time. Plus if you workout early in the morning there are many additional benefits to working out in a fasted state. Believe it or not, we “fast” everyday and the fast starts immediately after your last bite of food at night. That is why breakfast is called break-fast, because you are “breaking the fast”. When you train in a fasted state, you burn fat for energy not glucose. Remember when we say we want to lose weight we really mean we want to lose fat, so burning fat for fuel is a GOOD THING!
Our bodies are designed to burn fat, especially in the morning, do you think our ancestors woke up from a good nights sleep, walked to the kitchen and had a big bowl of Wheaties before heading out for the days hunt? Not likely, they probably woke up, started working (hunting and gathering), maybe taking a sample of berries here and there, and then ate a really big meal or two once all the work was done. Now obviously we don’t live in the “Caveman” days but the point is that our bodies are definitely designed to do work in a fasted state. Another piece of bunk fitness advice is that eating breakfast jump starts your metabolism. That is true in that your body will burn the sugar you introduced into your blood stream after fasting. But that is a whole other topic for a later time.
The main reason many people “need” to eat before class is because their diet is severely broken as a results of consuming way too many processed carbs. When you eat lots of processed carbs (cereal, bread, pasta, tortillas, cookies,etc) you constantly spike your blood sugar. When you spike your blood sugar your body releases insulin which helps regulate your blood sugar. After many years of eating lots of processed carbs your insulin sensitivity becomes damaged and you start to release too much insulin which causes a blood sugar drop. When your blood sugar is too low you can become very nauseous, feel very week, become light-headed and start to massively crave food (the need to eat before class). This crazy sine wave blood sugar effect (see picture below) happens because instead of burning fat (the bodies preferred energy source) our body is burning glucose.
Any processed carbohydrate or sugar you consume converts to glucose in your body. Glucose is basically sugar, so your blood sugar begins to rise very rapidly and because too much blood sugar can kill you your body must first “burn” the glucose before it burns fat. Because most of us eat way too many processed carbs we never dip into the fat burning zone, thus our broken diet keeps us constantly hungry and makes it very hard to lose body fat! Let’s not forget our body can only stores about two hours worth of energy in the form of glucose so it is a very inefficient fuel source that constantly need to be re-filled.
How do we start to burn fat? First lets start by significantly reducing the amount of process carbs we consume. Second let’s try working out on an “empty” (don’t eat anything 3 hours before class) stomach. Last but not least make sure you eat a big healthy meal after your workout! If you are not able to eat right after class, this is a great time to have a protein shake, fruit, raw nuts, or hard-boiled eggs.
I will talk about this more in the future but when I talk about working out in a fasted state, I am not advocating a reduction in your daily overall calories I am suggesting changing the type and timing of the calories you eat! As always please feel free to post comments or questions and do not hesitate to ask questions at the gym.