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45 inch chest: How big is it?

Learn how big a 45 inch chest really is for a natural lifter.
Written By  James Jackson
Last Updated on 6th June 2022
A bodybuilder with a big 45 inch chest

A 45 inch chest is definitely an above average male chest measurement. However, as you’ll soon learn, having a 45” chest is no guarantee of having well-developed pectorals.

That’s right; building an aesthetic physique is about more than just maxing out your circumference measurements.

Related Chest Size Guides:

Is a 45 inch chest big?

A bodybuilder measuring his big 45 inch chest

Is a 45 inch chest big or not? Yes, a 45 inch chest is definitely big and is at least 3 inches larger than average. The men who have a 45” chest tend to either be overweight or perform frequent bouts of resistance training.

If you take a walk into any city or town, you’ll see plenty of men who have a 45 in chest. However, it’s much rarer to see a muscular 45 inch chest—even in the gym.

That’s because your body fat level, back development, and ribcage size all affect how big your chest circumference is.

For example, it’s conceivable that someone could have a 45 inch chest measurement due to having a massive rib cage (while having relatively underdeveloped pecs).

The same holds true for the back. You could have really wide lats and thick traps but pretty poor pectoral development.

In other words, a given circumference measurement (up to a point) is no guarantee of having a well-developed chest.

What shirt size is a 45 inch chest?

A man with a 45 inch chest shirt size

In most brands of men’s clothing, a 45 inch chest means that you’re either on the upper end of a size large or on the lower end of a size extra large (XL).

So, if you want a tighter fit (perhaps one that shows off your physique), go with the large.

But if you want a more regular fit, the size XL is the way to go.

Obviously, you’ll need to factor in your height as well. If you’re a relatively short bodybuilder with a 45 inch chest, then it might be impractical to wear an XL. In this case, you might want to look into getting tailored shirts.

How can you expand your 45" chest naturally?

A man doing a wide grip bench press

Since a 45” chest is already pretty big, you’re going to need to put in some serious effort if you want to surpass your 45 inch measurement.

Other than increasing your training volume and pushing yourself that bit harder in the gym, there’s not much that you can do differently to expand your 45 in chest.

If you increase the resistance on a consistent basis—on both your chest and back exercises—then your circumference measurement will increase.

I recommend focusing on exercises that really put your muscles under a deep weighted stretch during the eccentric phase of the rep because these lifts tend to produce the most hypertrophy. So for your chest, dumbbell bench presses are likely your best bet. For your lats, pulldowns or pull-ups are the way to go.

On the diet side of things, slowly increasing your body weight by eating in a moderate calorie surplus will lead to a concurrent increase in chest circumference. Just don’t gain too much body fat. Otherwise, your chest might end up looking worse rather than better.

Conclusion: Do many people have a 45 in chest?

A man showing his 45 inch chest

There are plenty of people who have a 45 in chest due to being overweight or obese (in terms of fat mass). But despite what you may read online, it’s actually not very common for a natural lifter to have a lean 45” chest.

Unless you have a big frame, you simply don’t build a 45 in chest by doing a few push-ups or lifting weights for a year. Building a solid 45 inch chest takes years of training, so don’t feel inadequate if your chest is a good few inches behind.

At the same time, if you have a relatively low body fat level and you have a 45” chest, then you should definitely be proud of your accomplishment. If you want to keep gaining from here, make sure to focus on your back muscles as well as your chest since the lats really do contribute a lot of mass to your upper body size.

James Jackson
James Jackson is a personal trainer who uses his expertise in strength and conditioning to create helpful workout tutorials that show fitness enthusiasts how to build muscle while staying safe in the gym. He draws on the latest sports science data as well as tried and tested training techniques to get the best results for his clients without them having to live in the gym.
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