Why You Should Work Your Abs First

Your core—the dozens of muscles between your shoulders and your hips—contracts first in every exercise, he explains. All the energy you exert starts in your midsection, and is then transferred to your limbs.

A strong core allows you to apply more force to a barbell, whereas a weak core decreases the amount you can apply.

But in order to prime your core muscles so they fire better during your workout, you need to train your core right after your warmup, he says.