The key to any arm workout is intensity. There is no better way to ensure the intensity of an exercise than to take the average volume you would do and condense it into a much shorter period of time.
In this video, Jeff Cavaliere from YouTube channel Athlean-X show you an arm workout with just four biceps and triceps exercises that you can complete in 8 minutes or less that will spark all kinds of arm gains.
The setup for the workout is easy. All you need is a single pair of dumbbells, a bench that you can adjust to an incline and a pullup bar. You want to start with just two arm exercises, the hands out incline curl for your biceps and the incline dumbbell triceps extensions for the muscles on the other side of your arm. Choose a weight that you can perform 12 reps to failure on in your weaker of the two exercises. In this case, it is the triceps extension for me.
Start by performing a set of the hands out incline curls to failure. As soon as you cannot complete another rep lift the dumbbells up overhead and go right into your overhead triceps extensions. Here again, you will want to go until you cannot perform another quality rep and your triceps are fatigued. Back again to the incline curl where you want to perform as many reps as you can to failure. You keep bouncing back and forth between these two arm exercises until you can’t complete any more meaningful reps.
This will happen rather fast because as you fatigue in one arm muscle group you will have a shorter rest time before having to complete reps for the other muscle. By virtue of this short rest time, you will eventually fail out in both exercises. At this point, however, you are only half way through your workout. This occurred in just 4 minutes for me.
Move on immediately to the next pair of exercises in this 8-minute arm workout. Here you want to do a bicep chin curl hold. The goal here is to squeeze your biceps as hard as you can to maintain your position on the bar. Even as you fatigue, you want to keep trying to contract your arms as hard as you can and fight the drop. Once you cannot hold it anymore, go right to the floor and crank out reps of the cobra pushup.
You want to concentrate on squeezing the triceps hard at the top of every pushup. The benefit to this triceps exercise over others is that you finish with your arm in extension behind your body, so you are actively contracting the long head of the triceps as well. Rep out and get back up on the bar again. Keep alternating these biceps and triceps exercises until you once again cannot perform any more meaningful reps of either exercise.