If toning the back of your arms is a goal, strengthening the triceps can help eliminate that common trouble spot that jiggles when you wave and help you feel more confident. But even more important, ...

While having toned biceps is certainly a flex—literally—that’s not the only muscle you should work on arm day. To build all-around upper-body strength (oh, and gain even more muscle definition in your ...

Beth Skwarecki is Lifehacker’s Senior Health Editor, and holds certifications as a personal trainer and weightlifting coach. She has been writing about health for over 10 years. Arm day can be one of ...

Dr. Shields is a physical therapist with a background in English Literature and a passion for healthcare and education. She hopes to combine her clinical expertise with her love of writing, establish ...

The triceps brachii is a three-headed muscle that plays a critical role in elbow extension, pressing strength, and upper arm development. Its long, lateral, and medial heads each contribute ...

Tricep exercises may be overlooked in favour of the better known biceps, but they're arguably the most important muscle to train on arm day, as triceps make up two thirds of your upper arm.

On the backside of each of your upper arms is an unsung hero. With the right amount of consistent, balanced strength training, you can give it the attention it deserves—and in doing so, stretch the ...

When people think of having strong, toned arms, they tend to focus mainly on building biceps—the meatier part of your arms. But the triceps—the three-headed muscles in the back of your arms—are just ...

Training your triceps helps tone your arms, making them stronger and more defined. Strong triceps support your upper body during everyday movements and improve your ability to push and lift. Adding ...