If you want stronger arms, it isn't always enough to just do barbell curls and tricep rope pulldowns, you need to add some compound movements to get your arms from noodle arms to nuclear arms.
The following exercises don't directly work the biceps and triceps, but they still require movement at the elbow joint, so the biceps and triceps are still engaged.
Also note, that the benefit of doing these exercises is that you can use heavier weight, so you are stimulating the muscles with more weight which will help them grow.
In No Particular Order
1. Lat Pulldown
The lat pulldown (pulling the bar down with your lats) is one of my favourite exercises, and it stimulates the biceps, forearms and the lats.
You are getting a degree of elbow flexion as well as shoulder extension, plus some isometric stimulation of the biceps and forearms.
2. Bench Press
This exercise targets the triceps very well, due to a lot of elbow extension, and you are able to overload the muscle with lots more weight than usual because of using the bar.
You can also move your hands closer and turn it into a close grip press to target the triceps even more.
3. Spiderman Push Ups
One of the many benefits of this exercise is how stronger your arms and shoulders become under your own bodyweight.
Your triceps and biceps are working together to maintain stability of the humerus, as well as the rotator cuff muscles working to keep the humeral stable in the shoulder joint.
Remember, these exercises do not directly strengthen the arms, but they have a few key component that other arm exercises don't have:
1. Core Bracing
Due to the amount of weight that you can lift per exercise, there is a requirement for a specific amount of stability needed to perform each exercise as efficiently as possible.
To create this stability, to engage the core muscles for spinal stability and keep the torso tense, we need to take a deep breath into our stomach to create intra-abdominal pressure.
Once we get this pressure, we can move a lot more weight, helping us get stronger
2. Shoulder Stability
Each of these exercises was chosen because they challenge the shoulder joint to a degree.
During the bench press, the head of the humerus must remain in alignment in the shoulder socket to allow the pec and tricep muscles to properly engage and move the weight.
The muscles of the rotator cuff are always working together to keep the humerus inside the shoulder joint, especially if there are external forces acting in a particular direction on the shoulder, such as with a bar pushing down, in a posterior direction to the body.
Similar to the bench press, but in a pulling motion, this time superior to the shoulder.
The scapula downwardly rotates/depresses to help the shoulder remain locked in, again the rotator cuff muscles work together to keep the humerus within the socket of the shoulder and preventing any unnecessary strain.
Spiderman Push Up Hold
Without argument the most difficult exercise of the 3, the spiderman push up is a mixture of a knee raise to strengthen the hip flexors, a push up to strengthen the chest, arms and shoulders, and a plank to engage the core isometrically, as well as the glutes and quads.
It's pretty obvious that without the arms, you would be flat on your face, and your arms take all your bodyweight.