Jerry Brainum Full Interview | The Truth Behind Body Fat, Biggest Physique Mistakes, & More

Watch the full uncut GI Exclusive interview with Jerry Brainum.

Jerry Brainum has been a science writer, researcher and lecturer for more than 30 years in the bodybuilding industry. Throughout those 30 years he’s amassed a superset of knowledge. He’s shared that knowledge in our original series Straight Facts in the past and continues to do so via Applied Metabolics.

We reconnected with Jerry Brainum this past year for a new video interview to discuss the science behind bodybuilding. Jerry Brainum helps shed some light and debunk some myths on bodybuilding training, diets, and trends in the sport.

Over the past few months we’ve released multiple GI Exclusive segments from our interview with Jerry Brainum. Now we’re releasing the full length interview including topics such as the reality behind body fat percentages, the biggest mistake that makes bodybuilders look flat, and the best physiques of all time.


Listen To Our Jerry Brainum Interview On The Generation Iron Podcast

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Listen to the full Jerry Brainum interview here:


The Realities Behind Bodybuilder Body Fat Percentage & Cutting Weight

Brainum claims that the usual body fat percentage of a pro bodybuilder falls around 5%-7%. In some extreme cases, a bodybuilder might be able to go down to 3% overall body fat percentage. He stresses that this is extremely rare. He also stresses that any bodybuilder that claims to have less than 3% is lying. Brainum states that it’s humanly impossible to achieve that low of number. However, during a cutting phase, your body will dip into fat storage. With a well-adjusted diet, the right premium fat-burners accelerate fat loss by enhancing metabolism, reducing food cravings, and increasing intra-workout energy to support muscle growth.

Jerry Brainum also discusses just how vital genetics plays a roll in how a person can gain or lose weight. The unfortunate truth is – some bodybuilders will have to struggle a lot more to bring their body fat percentage low enough to compete successfully. Everybody is genetically different. But in a world of bodybuilding where physiques need to all match the same standard, some competitors will struggle much more than others.

Jerry Brainum details the specific genes that determine such fate for bodybuilders (and any person really). He also spends some time debunking popular weight loss tactics such as fat freezing and liposuction. The overall truth is one many probably don’t want to hear. These medical procedures don’t always work. They can also damage your cells permanently. Ultimately, there is no easy way to lose weight. If you are someone who struggles to lose weight – you just have to work harder on good nutrition and exercise.

The Biggest Mistake That Makes Bodybuilder Muscle Look Flat

Jerry Brainum points out that muscle tissue is made of 72% water. So when bodybuilders deplete themselves in the final “hell week” before a show, if they go too far they actually lose the fullness of their muscle. Even furthermore, some competitive bodybuilders don’t even realize that drinking water is in itself a diuretic. Water flushes out a lot of extra minerals in your body the more you drink it. Thinks like sodium. Too much sodium can make you retain more water – which is a big problem for bodybuilders.

So the biggest mistake that bodybuilders make is by often drinking too much water, not drinking any at all, or taking too many diuretics in the final week before the show. With one fell swoop, it can destroy a year’s worth of work. The hard part of course, is to know how much is too much. Each body is different – but the key is for athletes to recognize this is part of the problem first. Then they can start learning their body and how to fix it.

It’s a delicate balance. It’s what makes this sport so challenging. It’s what makes the legends that much more impressive. Never underestimate “hell week” and start taking depletion seriously in order to present the best bodybuilding physique on stage.

Wrap Up

Jerry Brainum is a man who can provide rare in-depth knowledge on all things bodybuilding from a scientific perspective. He has always ensured that his statements are backed by rigorous research and not “broscience” or anecdotal experiences. That’s why our latest uncut interview is essential viewing for anyone looking to take their physique to the next level.

You can watch our full uncut GI Exclusive interview with Jerry Brainum above.