We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What is a Deltoid Muscle?

Mary McMahon
Updated Mar 03, 2024
Our promise to you
The Health Board is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At The Health Board, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject-matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

The deltoid muscle is the muscle that gives the shoulder its rounded shape. Many mammals have this muscle, as the design is very efficient, and this muscle is responsible for the abduction of the shoulder and some of the rotation of the arm or limb. In humans, the deltoids are a common target of weight training, with people engaging in activities like presses to develop and strengthen them. In people with very well defined musculature and low body fat, the deltoid is often highly visible on the shoulder and upper arm.

This muscle has three heads. The posterior deltoid originates at the scapula, while the anterior and lateral deltoids connect with the collarbone. The other end of the muscle attaches to the humerus, the armbone. Structurally, the muscles resemble triangles, or the Greek letter Δ (delta).

The primary function of this muscle is to abduct the shoulder. When people rotate a shoulder, the deltoid muscle does much of the work, guiding and stabilizing the movement. Outward rotation of the arm also involves the muscle. In a classic example of this muscle at work, people who swing their arms while walking are relying heavily on the it for the swinging motion.

The axillary nerve, which originates in the brachial plexus, a tight bundle of nerves near the neck, is responsible for innervating the deltoid muscle. Problems with the function of the muscle can arise both as a result of damage to the axillary nerve and as a result of damage to the muscle itself. Strain is a common problem with the shoulder muscles, and can be caused by overextension or lifting too much weight. The symptoms of strain include the sudden onset of pain and soreness, as well as stiffness in the muscle and a limited range of movement.

For mild strains, ice and rest are often enough to allow the muscle to recover. Some patients also find the application of hot compresses beneficial. More severe strains may require treatment, such as physical therapy or medication, to manage pain while the muscle heals. If the axillary nerve is damaged, patients may lose muscle control or notice tingling and painful sensations. Nerve damage may resolve if it is mild, or be retained if it is more severe. A neurologist can conduct an examination to determine whether or not the nerve is really damaged and to determine the severity of the problem.

The Health Board is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Mary McMahon
By Mary McMahon

Ever since she began contributing to the site several years ago, Mary has embraced the exciting challenge of being a The Health Board researcher and writer. Mary has a liberal arts degree from Goddard College and spends her free time reading, cooking, and exploring the great outdoors.

Discussion Comments
By rugbygirl — On Jun 06, 2011

@Kat919 - I've seen it both ways. Some people say that raising your hands too high will hurt your shoulder, while others say that raising up to just above your shoulders is how to really build deltoid muscle.

I'm not an expert, but I always follow the rule of listening to your body. If you work out, you probably know the difference between "good" pain (i.e., fatigue) and "bad" pain (something going wrong). Personally, I don't lift my hands higher than mu shoulders because my shoulder "pops" when I do that. I figure popping sounds are bad, and I try to avoid them!

By Kat919 — On Jun 05, 2011

Years ago, I was told that when you're doing deltoid exercises, you should never raise your arm above the level of your shoulder. (I'm basically talking about flies here, when you hold a weight in each hand and slowly raise your arms, keeping them more or less straight.) I think the idea was the it was bad for your shoulder joint.

The last couple of exercises classes I've been in, though, I've seen the instructor raising her hands noticeably higher than her shoulders. Has this rule changed? Did it turn out to be OK to do that?

Mary McMahon
Mary McMahon

Ever since she began contributing to the site several years ago, Mary has embraced the exciting challenge of being a...

Learn more
The Health Board, in your inbox

Our latest articles, guides, and more, delivered daily.

The Health Board, in your inbox

Our latest articles, guides, and more, delivered daily.