The exercises in our 30-day arms challenge use your own body weight for the first half of the month, and then up the intensity by incorporating dumbbells for the second half. All six moves below will target your biceps (the front of your upper arms), triceps (back of the upper arms) and deltoids (shoulders).

Here’s what the workout split for the four phases looks like for this 30-day arm challenge: Strength A: Days 1-8 Hypertrophy A: Days 9-16 Strength B: Days 17-23 Hypertrophy B: Days 24-30