Pete McCall by Pete McCall

Want to add a little definition to your arms so you can show them off the next time the sun is shining? If toned arms are what you’re after this summer, try this strength training workout.

Strong, well-defined arms create a visual effect that lets others know that you make physical activity an important component of your life. You can change the look of your arms fairly easily, because the relatively short structures of the arm muscles allow them to quickly adapt to strength training.

The biceps brachii on the front of the upper arm has two attachments on the scapula (shoulder blade): the origin of the short head originates at the coracoid process of the scapula and the long head starts at the supraglenoid tubercle. Both muscles merge together and attach to the radius bone of the forearm and produce three distinct movements:

  • Elbow flexion—bending your elbow to bring your wrist closer to your shoulder
  • Shoulder flexion—raising your arm in front of your body
  • Supination—rotating your wrist to turn your palm up to face the ceiling

The triceps have three separate portions which attach the scapula and the humerus (upper arm bone) to the ulna bone of the forearm. The muscle attaches past the elbow, and since it crosses both the shoulder and elbow joints it can create the following movements:

  • Elbow extension—straightening your arm to move your wrist away from your shoulder
  • Shoulder extension—moving your arm past your body toward your backside

While many people may be familiar with these larger muscles there are three other muscles which are very important for helping to improve definition of the arms: the coracobrachialis, the brachialis and the radiobrachilias. Lying under as well as next to the biceps, these muscles connect the shoulder blade, upper and lower arm bones, respectively. The secret to quickly improving the look of your arms is to do exercises which engage and activate these three muscles. Changing the look of your arms can be accomplished with a few simple moves that involve rotating the wrists to engage the coracobrachialis, brachialis and radiobrachilias.

The following workout can help give you guns worth showing off the next warm day. Complete all sets of each exercise before moving on to the next one. For best results perform all repetitions of each exercise to the point of fatigue where doing another repetition is not possible.

This workout can be done by itself or on days when you do cardio exercise or core-specific training.

Suns Out, Guns Out



Rest Interval


Supinating dumbbell curls

Hold one dumbbell in each hand, starting with your palms facing your body. As you lift the weight and bend the elbow rotate your wrist so your palm faces up toward the ceiling; this rotating motion involves both the biceps and smaller arm muscles.


45 seconds


Triceps push-ups

Perform push-ups on the ground. Keep both hands close to your body (almost under your shoulders) so that your elbows point toward your feet as they’re bending to lower your body to the ground; perform as many push-ups as possible.

To fatigue

45 seconds


Dumbbell hammer curls

Hold one dumbbell in each hand so that your palms face your body and your thumbs are on top. Keep your elbows close to your body as you slowly lift and lower the weight; this hand position focuses on the smaller muscles under the biceps.


45 seconds


Lying triceps extension with rotation

Lie face-up on a bench, hold one dumbbell in each hand with both arms extended straight up. Keep your palms facing each other as you lower the weights toward your shoulders. As you straighten your elbows to return the weights to the top, rotate both hands so the palms face the ceiling at the top of the move.


45 seconds


Alternating between biceps (front) and triceps (back) keeps both muscles under tension, which can help increase size and definition in a shorter period of time.

*For best results perform all reps until momentary fatigue, where another rep is simply not possible.

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