This complex strength move is a classic for a reason: it engages a handful of muscles throughout the upper body, including the deltoids (the muscles that cover the front, side, and back of your shoulder), serratus anterior (the muscle on the sides of your ribcage), lower and upper traps, pectoralis major and minor, rhomboids (the muscles connecting your shoulder blades to your spine), triceps, and more, according to research in the journal Sensors.. To top it off, it calls on your core for stability and requires mobility throughout the thoracic spine (which extends from the base of your neck to the bottom of your ribs).
As you fatigue during this five-minute arm workout, you may lose core engagement and find yourself excessively arching your lower back (hello, discomfort). If that's the case, take a small step back with one foot, which will help you keep your shoulders, hips, and knees aligned.
- Stand tall with your feet hip-width apart, a soft bend in your knees, and a dumbbell in each hand. Engage your core by bracing as if someone is about to punch you in the stomach. Curl the dumbbells up to your shoulders, then open your elbows out to the sides, slightly in front of your ribcage. Your palms are facing forward. This is the starting position.
- Keeping your core engaged and spine neutral, take an inhale. On an exhale, simultaneously press the dumbbells up to the ceiling until your arms are straight but not locked.
- On an inhale, reverse the movement, bending your elbows and lowering the dumbbells to shoulder height. That's one rep.
Do 8 reps in Round 1. Each round after, take away 2 reps.
