The word bulking conjures up images of stuffing mass amounts of food into your mouth for extended periods of time. In most cases, when a natural bodybuilder begins a bulking period, it lasts for several months in a row. Maybe you've attempted a bulk like this?

I'm here to set the record straight: bulking for extended periods of time is a bad approach.

The Benefits of Bulking

Bulking works, but it works best in two week spurts. During times of over-feeding, the body becomes a growth machine.

Fat storage activity in the body doesn't instantly kick into overdrive when bulking begins. It's not a light switch reaction. Simply put, when you over-eat, it takes a while for the body to transition to "fat storage" mode. During this transition period, your body is a muscle building machine.

During the first 14 days of a bulk, several studies have revealed that testosterone, IGF-1, and insulin levels elevate. What does this mean? You are highly anabolic. You are as anabolic as you're going to get as a natural bodybuilder.

Benefits of Aggressive Bulking Peak at 14 Days

But the anabolic benefits of bulking peak after 14 days. During this time, and as I mentioned, the body is slowly transitioning over to fat storage mode. After 2 weeks on a bulk, you lose most of the anabolic benefits, and start to store fat at an alarming rate.

If you continue to aggressively bulk after this point, more of your gains will be fat. Of course, each individual is different. Some may continue to gain more muscle for several days after the 2 week period. And some may start to add fat earlier then predicted. But in general, 2 weeks is the optimal bulking period.

As one can project, once your current bulk ends, you should refrain from another bulking cycle for at least 2 weeks. Again, the body needs time to transition from a fat storage machine into a fat burning machine.

During this transition time, it is recommended that you eat slightly below caloric maintenance levels. Because the body is ready to store fat, eating "normal maintenance calories" could cause you to gain unwanted fat. By eating slightly below maintenance levels, you will encourage the body to transition to fat burning mode. Thus begins the prepping cycle for the next bulk.

Healthier, non-processed foods allow the body to function better, so clean bulking keeps the body running more efficiently.

What About Hardgainers?

A hardgainer is a person who has difficulty gaining weight either through diet or exercise.

After reading this, hardgainers might fear the post-bulk, low calorie period. After all, they have a hard time gaining muscle, and don't want to lose what they've just gained.

Here's the good news: during 2 week bulking cycles, studies reveal that you will gain primarily muscle. (I will list the studies at the end of this article) And during post-bulking, "cutting" periods, you lose primarily fat.

The bottom line is that over a 28 day bulk/cut, you gain muscle, and gain very little fat. If you gain 3 pounds of muscle and 2 pounds of fat over a 14 day bulk, and lose 1 pounds of muscle and 2 pounds of fat during the 14 day cut...

You will have gained 2 pounds of muscle and ZERO pounds of fat over a 28 day period.

Now, repeat this cycle each month, and you will be well on your way to packing on muscle mass.

Is Muscle Memory a Myth?

Muscle memory is not a myth. Once a muscle has reached a certain size, it tends to be MUCH easier to obtain that size again. So, if you gain 2 pounds of muscle on a 2 week bulk, but end up losing a couple pounds of that during the subsequent cut...have no fear. Muscle memory will make it much easier to regain that muscle the next time you bulk.

Dirty or Clean Bulk?

Is it best to eat dirty or clean calories during a 2 week bulk? Generally, it doesn't matter. A calorie is a calorie is a calorie. Many will disagree with me. I encourage them to read the science behind this bulking protocol.

But with that said, healthier, non-processed foods allow the body to function better, so clean bulking keeps the body running more efficiently. It is very difficult to eat enough calories on a clean bulk. I recommend eating clean most of the time, but allowing room for pizza, chips and ice cream.

Make sure you continue your pattern of frequent feedings. Eat at least 30 grams of protein 5-6 times per day on a bulk. And eat huge post-workout. Huge!

Calories Needed During a Bulk

How much should you eat during bulking and cutting periods? To answer this question, you first need to discover your caloric maintenance level. Log everything you eat, and find the calorie level that keeps your weight the same for a 2 week period.

Once you know this number, eat at least an additional 1,000 calories per day on a bulk. Remember, it takes time for the body to transition over to fat storage mode, so eating more then 1,000 calories over maintenance level isn't a bad thing at all. I would recommend eating more then this the first week of a bulk, and cutting back to surplus of 1,000 during the second week.

Following the bulk, immediately cut back your calories to 500 below maintenance - and keep them there for the entire 2 week period.

The Studies

For more information on the research behind the science of bulking, I encourage you to Google the following studies:

"Changes in macronutrient balance during over- and underfeeding assessed by 12-d continuous whole-body calorimetry." Jebb S A; Prentice A M; Goldberg G R; Murgatroyd P R; Black A E; Coward W A

"Hormonal response to overfeeding." GB Forbes, MR Brown, SL Welle and LE Underwood

"Short-term, mixed-diet overfeeding in man: no evidence for ‘luxuskonsumption.'" Ravussin E, Schutz Y, Acheson KJ, Dusmet M, Bourquin L, Jéquier E.

End Notes

No approach to bulking and cutting will ever yield the same results for 2 individuals. It is up to you to experiment, and log results. If you are gaining too much fat on a bulk, either pull back the amount of calories you are eating, or shorten the bulk up by one day. It is best to make small movements when trying to zero in on the perfect plan for your body.

I highly recommend purchasing a skin fold caliper, and logging weekly fat, and lean body mass levels. Only by doing so will you know your true lean muscle mass levels. Body fat scales are highly inaccurate. Under no circumstances should you utilize one to estimate the effectiveness of a bulking/cutting plan.